Title: Link pin beam Post by: Fankii-T on December 03, 2012, 22:07:05 pm Hi all, I'm Frank from Norway.
Been lurking around here for quite some time now, loving this forum! Haven't really wanted to post anything, not owning either a Cal-look or a fast beetle. Joining discussions without really had any work done wouldn't help me out a lot and make a headache for you guys. So go easy on me ;D I've got a 65 beetle, at first I wanted a nice solid patina, saw it as a financially good way to enter the air cooled world. Been fun, bought a narrow beam, spindles, did brakes bearing and so on. Took it apart again to weld the battery area and inside the rear wheel wells, sandblasted the pan and all the parts that bolts up, painted it and put everything back together. Then due to work and trying to go to school at the same time I ended up not going to the garage that much. So it's been sitting still looking sorry for itself for 2 years now. But this summer school is done and my work schedule is looking pretty good, have to catch up with the two lost years, and do work. So, sorry for all the bla bla bla at the top there, just wanted to have a short intro on my first post. My beetle has a link pin beam, I'm over the whole slammed look. And I want to collect the parts to redo the beetle as a Cal-looker. To start at one end I'd like to change out the whole front end with period parts they used back in the days on the hot Cal-lookers, but with today's technologies is there a product that will make the ride more enjoyable, without being shiny and made in China? But also to withstand some beating from a bigger engine and possible some track action. Starting from the beam bolts, to beam, steering box, spindles, disc brakes and all in-between, what would make to ultimate front setup for a link pin beam? Money no object. Regards Frank Title: Re: Link pin beam Post by: hotrodsurplus on December 04, 2012, 18:21:36 pm Frank,
Here are two ways. There is no need to use any chinese parts with either method. For one method simply pull leaves. I suggest cutting the ends and centers from the leaves you pull and bonding them to the stack with epoxy so the pinch bolts will clamp properly. My first Beetle was done this way in the very early '80s and to this day it stands as the best riding Volkswagen that I ever had. It rode as well as stock. It was magical. The only drawback is the lack of ride-height adjustment. The more accepted way of course is with adjusters. I prefer the sway-a-way style--in fact I prefer Sway-A-Way brand as they are made in the US and are very high quality. In my experience the ride tends to get a bit stiffer than stock if lowering a car with adjusters and a full spring pack. My new favorite way is by using a combination of the two methods. On my current builder I pulled a few leaves to lower the nose just a little bit--maybe 1 1/2 inches. Before I install the adusters I set them in the middle of their adjustment range and weld them in so the pinch bolt matches the stock pinch-bolt location. Because the car sits a little bit lower when the pinch bolt is in the middle of the adjustment range I can really lower the car by setting the adjusters all the way down or raise it back up to stock height by setting the adjusters all the way up. It rides at least as well as or better than stock. Do not use the stock rubber or replacement urethane snubbers. They will prevent the suspension from moving when the car is lowered. Do not cut off the snubber mounts either. You can damage the damper and/or the damper tower if the suspension uses the dampers as a stopper. Instead, remove the stock rubber snubber and cut off the very tip of the snubber mount where it necks down (about 3/4-inch from the tip). Install the trailing arms and dampers that you intend to use but not the springs. Then heat and shape the snubber mounts so the arms hit the snubber mounts before the dampers fully collapse or extend. On a street car I set the stops so the damper stops 1/4-inch from fully compressing and about 1/8-inch from fully extending. It is important to set the stops by using the dampers you intend to run on the car. Not all dampers are the same length. The ends of the snubber mounts will flatten. I weld up the end to make it stronger. I also gusset the mount but that is optional. Do not use a 'lowered' damper. They are too short and valved improperly for an air-cooled Volkswagen (too stiff). A stock-type damper will let the suspension go so low that the tire will hit the fender or headlight bucket anyway. There is no need for a special-length damper. If you want stock ride quality (comfortable) then use stock-style non-pressurized dampers (Cofap was common here--probably still is). You can use a good monotube damper like a Bilstein if you pull leaves. It might ride too stiff if you use Bilsteins on a car that's been lowered with adjusters and a full spring pack. The exception would be if you used dropped spindles only and maintained the beam's stock ride height. It will ride stiffer than stock but it will not be objectionable. Use at least one set of caster shims regardless of the method you use (spindles, adjusters or pulled leaves). Lowering the front so it rides lower than the rear alters the caster regardless of the method you use. I typically run two sets of caster shims. Two sets requires longer bolts for the lower beam clamps. The stock bolts for the upper beam clamps will work with two sets of shims. Title: Re: Link pin beam Post by: benlawrence on December 04, 2012, 19:15:54 pm I did mine as hotrodsurplus 10 years ago removed the top and bottom leaves cut packers from the old leaves and put it all back together, the ride is too nice for me to even want to weld an adjuster in there
Title: Re: Link pin beam Post by: Fankii-T on December 04, 2012, 22:06:16 pm Hi guys, thanks for the reply. Love to hear about your setups, and how things were done a few years back.
My setup at the moment is a Slamwerks 4" narrow beam, narrowed stock leaves without any leaves removed. Some Kyb lowered shocks and one set of caster shims. It's really low but it's also a little too stiff at the front end, doesn't really like the ride. But the plan was different back when I bought the parts than what I'd like to do with it now. Have of course narrowed the tie rods as well and I got a bit of bump steer, bought some sockets to drill the spindle and flip the ends upside down, but didn't do it. For one method simply pull leaves. I suggest cutting the ends and centers from the leaves you pull and bonding them to the stack with epoxy so the pinch bolts will clamp properly. My first Beetle was done this way in the very early '80s and to this day it stands as the best riding Volkswagen that I ever had. It rode as well as stock. It was magical. The only drawback is the lack of ride-height adjustment. The more accepted way of course is with adjusters. I prefer the sway-a-way style--in fact I prefer Sway-A-Way brand as they are made in the US and are very high quality. In my experience the ride tends to get a bit stiffer than stock if lowering a car with adjusters and a full spring pack. I did mine as hotrodsurplus 10 years ago removed the top and bottom leaves cut packers from the old leaves and put it all back together, the ride is too nice for me to even want to weld an adjuster in there I liked that idea about a better ride over my setup, I will buy new leaves and try it out, thanks guys :) Got Sway-a-way style adjusters on my narrow beam now, but I've lately liked the design of the "Puma" style CB Performance is offering. More compact design, but you maybe get some more fine tuning out of the sway-a-ways. Do not use the stock rubber or replacement urethane snubbers. They will prevent the suspension from moving when the car is lowered. Do not cut off the snubber mounts either. You can damage the damper and/or the damper tower if the suspension uses the dampers as a stopper. Instead, remove the stock rubber snubber and cut off the very tip of the snubber mount where it necks down (about 3/4-inch from the tip). Install the trailing arms and dampers that you intend to use but not the springs. Then heat and shape the snubber mounts so the arms hit the snubber mounts before the dampers fully collapse or extend. On a street car I set the stops so the damper stops 1/4-inch from fully compressing and about 1/8-inch from fully extending. It is important to set the stops by using the dampers you intend to run on the car. Not all dampers are the same length. The ends of the snubber mounts will flatten. I weld up the end to make it stronger. I also gusset the mount but that is optional The beam I got now don't have the snubbers at all, and I've been thinking about what could happen if my shock bottom out. I will from this post keep them on my new beam, I'd like the part VW put them there for a reason, so why cut them? I think most aftermarket beams comes without them cause the off the shelf beams need to apply for people at stock hight and slammed. I'll keep mine and fine tune them for the lowered front, good point hotrodsurplus! ;D Do not use a 'lowered' damper. They are too short and valved improperly for an air-cooled Volkswagen (too stiff). A stock-type damper will let the suspension go so low that the tire will hit the fender or headlight bucket anyway. There is no need for a special-length damper. If you want stock ride quality (comfortable) then use stock-style non-pressurized dampers (Cofap was common here--probably still is). You can use a good monotube damper like a Bilstein if you pull leaves. It might ride too stiff if you use Bilsteins on a car that's been lowered with adjusters and a full spring pack. The exception would be if you used dropped spindles only and maintained the beam's stock ride height. It will ride stiffer than stock but it will not be objectionable. My lowered shock looks quality, but I feel they are too stiff, maybe they end up being better at the front if I'd used them with the leaves solution mention at the top. But since I'm not going for the slammed lock anymore, I should buy some quality stock height shocks. Bilsteins were mentioned in the qoute over here, any other quality options guys? Any adjustable? That could fine tune the ride? New questions to keep the ball rolling here :) Any steering box mods from back in the day? Fill me in with everything you got on steering mods! What is a Cal-look norm from narrowing the beam? Stock? 2", 4"? Regards Frank RT Title: Re: Link pin beam Post by: hotrodsurplus on December 04, 2012, 23:11:49 pm Quote My setup at the moment is a Slamwerks 4" narrow beam, narrowed stock leaves without any leaves removed. Some Kyb lowered shocks and one set of caster shims. It's really low but it's also a little too stiff at the front end, doesn't really like the ride. I think you are being generous about the ride quality. Please do not take this the wrong way but it has to ride simply dreadful. Remember, when you shorten a spring you increase its rate. The effective spring length of each side of the torsion pack is about 16 inches (subtract the broached area of the arm and the center mount). The effective length of each side of your spring pack is 14 inches (half of 4"). Cutting the 16-inch length 2 inches shorter increases the spring rate by 15 percent. That is a significant increase. The shorty dampers for king/link Beetles were derived from the '63-'82 Corvette IRS. The ones we sold were considerably stiffer than the stock-style KYB dampers which were excessively stiff in their own right. What's worse is that the shorty dampers are too short to allow any kind of droop (rebound) travel. That makes a suspension feel very jerky. I would advise playing with your existing suspension before doing anything else. Remove the dampers. Crank the adjusters all the way up. Then start pulling leaves until the suspension starts moving freely. You don't have to pull the arms nor do you have to do the shim trick just yet. Just raise the front, loosen the grub screws, pull the outermost leaves in each pack, tighten the set screw, set the car down on the ground, and push down on the front to see how it feels. Once you are satisfied with the spring rate then cut the areas of the leaves that fit where the grub screws pinch the leaves and epoxy them to the remaining plates. Sell those KYBs to someone else. Buy a pair of stock dampers. You can use those on the new beam that you build. Marvel at the incredible ride quality. Then, if you want to build a full-width beam, you can use your new dampers on it. As Ben noted the ride will improve greatly Quote Got Sway-a-way style adjusters on my narrow beam now, but I've lately liked the design of the "Puma" style CB Performance is offering. More compact design, but you maybe get some more fine tuning out of the sway-a-ways. Berg used to push those Avis adjusters and when I thought Berg could do no wrong I thought they were the cat's pajamas. Then I worked on a car that had them. You have to jack up the front, loosen the bolts, let the front down and guess where you think the adjusters should land, clamp the adjusters, and set the car back down. Of course you won't like how the car sits so you'll do the same process again and again until you mumble, "Aww, fuckit" and live with the ride height. I know people have perfected the method but i can think of more important things to do. Worst of all, you almost never get the same setting if you have to jack up the car to tow it. Berg used to gripe about cutting the beam to install conventional adjusters. I could see how this was a problem with the old Select-A-Drop adjusters as you literally cut the upper beam in half and the center just rotated freely. That's a poor design. But the Sway-A-Ways weld into the beam. A properly prepared and welded butt joint is as strong as the parent material. At the Lincoln Welding school in Cleveland the instructors go out of their way to prove it with destructive testing. If that's not enough, consider that just about every hardcore off-road beam car uses the Sway-A-Way adjusters. If they can handle it, our street-driven cars are well safe. Use whichever design quacks your duck but I prefer the ease and fine range of adjustment with the Sway-A-Ways adjusters. Quote The beam I got now don't have the snubbers at all, and I've been thinking about what could happen if my shock bottom out. I thought about that after I posted and came to the conclusion that the tire will likely hit the fender before the damper bottoms out. Quote I'll keep mine and fine tune them for the lowered front, good point hotrodsurplus! ;D Glad that helped. Remember, though, you will have to modify them for full travel. Actually, I have a photo of a snubber that has been modified for travel. It is on Eric Solorzano's short-course Class 11 car. People call Solorzano the Class 11 king because he has won his class at the Baja 1000 eight times, the most that anyone has ever won. That is the slowest class (36 hours-plus) and it uses almost all stock VW parts. If the design works for him it will work for us. [attachment=1] Quote My lowered shock looks quality, but I feel they are too stiff, maybe they end up being better at the front if I'd used them with the leaves solution mention at the top. I think they are too stiff for even that application. I know they are too stiff for a stock beetle--they will jar your teeth out. Reducing the spring rate will make it slightly better but the damper length is also an issue. They are just too short to offer good ride quality. And too stiff. Quote Bilsteins were mentioned in the qoute over here, any other quality options guys? Any adjustable? That could fine tune the ride? People love the Koni dampers but they are just an inexpensive twin-tube damper (think of a tiny cylinder within the damper tube and a bunch of oil that prevents heat from transferring efficiently). They use an antiquated base valve for compression damping. A base valve usually uses a series of ports with tiny check balls and springs. A hole will flow only a set rate of fluid before it hydrostatically locks. A stock damper is also a twin-tube design but the valve network is loose enough that they won't hydrostatically lock in most applications. The Koni 'adjusts' by covering the ports in the base valve. It stiffens the damper but that also increases the incidence of hydrostatic lock. The springs in the check balls also wear out in time. Also, a Koni doesn't benefit from high pressure to reduce cavitation and therefore heat. A Bilstein is a monotube design--the damper body is the cylinder itself. It uses over-sized ports and Belleville springs for damping. The springs deflect in a controlled manner as flow increases and will prevent the damper from hydrostatically locking. The Koni dampers have a very limited adjustment and once you set it the damping force remains the same for all occasions. The Bilstein dampers on the other hand constantly self adjust to match road conditions. I think you would be happier with the stock damper, though. It will give you the very best ride quality. A stiffer damper will not necessarily make a car handle any better but it will usually make it ride harsher. I have Bilsteins in all of my cars except my lowered Beetle. Quote Any steering box mods from back in the day? Fill me in with everything you got on steering mods! Stock box installed and centered properly. Nothing more really. Quote What is a Cal-look norm from narrowing the beam? Stock? 2", 4"? 0". The narrowed-beam thing came about in the '90s when people started slamming cars. Some people have to narrow their beams about 2 inches to compensate for offset variations caused by aftermarket wheels, poorly designed disc brakes, and dropped spindles. A true traditional Cal Look car is rarely low enough to cause the tires to rub the fenders. Title: Re: Link pin beam Post by: Fankii-T on December 05, 2012, 01:39:03 am Quote My setup at the moment is a Slamwerks 4" narrow beam, narrowed stock leaves without any leaves removed. Some Kyb lowered shocks and one set of caster shims. It's really low but it's also a little too stiff at the front end, doesn't really like the ride. I think you are being generous about the ride quality. Please do not take this the wrong way but it has to ride simply dreadful. Yes I'm being generous, it sucks! ;D Remember, when you shorten a spring you increase its rate. The effective spring length of each side of the torsion pack is about 16 inches (subtract the broached area of the arm and the center mount). The effective length of each side of your spring pack is 14 inches (half of 4"). Cutting the 16-inch length 2 inches shorter increases the spring rate by 15 percent. That is a significant increase. Thanks for sharing this, great info! I would advise playing with your existing suspension before doing anything else. Remove the dampers. Crank the adjusters all the way up. Then start pulling leaves until the suspension starts moving freely. You don't have to pull the arms nor do you have to do the shim trick just yet. Just raise the front, loosen the grub screws, pull the outermost leaves in each pack, tighten the set screw, set the car down on the ground, and push down on the front to see how it feels. Once you are satisfied with the spring rate then cut the areas of the leaves that fit where the grub screws pinch the leaves and epoxy them to the remaining plates. Great info again, thanks a lot for this! Just to get this right, remove both of the smallest leaves in each pack. The one facing the grub screw and the one farthest away from it, or try first by just pulling one in each pack? Sell those KYBs to someone else. Buy a pair of stock dampers. You can use those on the new beam that you build. Marvel at the incredible ride quality. Then, if you want to build a full-width beam, you can use your new dampers on it. As Ben noted the ride will improve greatly New stock dampers noted ;) Quote Got Sway-a-way style adjusters on my narrow beam now, but I've lately liked the design of the "Puma" style CB Performance is offering. More compact design, but you maybe get some more fine tuning out of the sway-a-ways. Berg used to push those Avis adjusters and when I thought Berg could do no wrong I thought they were the cat's pajamas. Then I worked on a car that had them. You have to jack up the front, loosen the bolts, let the front down and guess where you think the adjusters should land, clamp the adjusters, and set the car back down. Of course you won't like how the car sits so you'll do the same process again and again until you mumble, "Aww, fuckit" and live with the ride height. I know people have perfected the method but i can think of more important things to do. Worst of all, you almost never get the same setting if you have to jack up the car to tow it. Berg used to gripe about cutting the beam to install conventional adjusters. I could see how this was a problem with the old Select-A-Drop adjusters as you literally cut the upper beam in half and the center just rotated freely. That's a poor design. But the Sway-A-Ways weld into the beam. A properly prepared and welded butt joint is as strong as the parent material. At the Lincoln Welding school in Cleveland the instructors go out of their way to prove it with destructive testing. If that's not enough, consider that just about every hardcore off-road beam car uses the Sway-A-Way adjusters. If they can handle it, our street-driven cars are well safe. Use whichever design quacks your duck but I prefer the ease and fine range of adjustment with the Sway-A-Ways adjusters. I never thought about the avis (that I referred to as CB's puma) in that way, but when I visualize the design in my head I can surely see the lack of the adjuster screw would make a lot of tries with the car on and off the jack to get it right. Good point there, and I haven't had any issues with it on my current beam. Design wise I think it looks better, but function before form! But also there is an issue about the EU as we call in in Norway, MOT in the UK (possible TUV in EU?), every second year we have to get the car inspected, a random workshop would maybe let it pass. But it's a good thing to have it written on paper that you are allowed to use a lowered front end if you get pulled over, and the CB puma beam has been classified as legal, but I think you have to tack weld the outer plate in place. So that you can't lower it more after the inspection. I want the car to be right this time, so I maybe have to live with avis design. Quote The beam I got now don't have the snubbers at all, and I've been thinking about what could happen if my shock bottom out. I thought about that after I posted and came to the conclusion that the tire will likely hit the fender before the damper bottoms out. Haha, you're right! ;D Quote I'll keep mine and fine tune them for the lowered front, good point hotrodsurplus! ;D Glad that helped. Remember, though, you will have to modify them for full travel. Actually, I have a photo of a snubber that has been modified for travel. It is on Eric Solorzano's short-course Class 11 car. People call Solorzano the Class 11 king because he has won his class at the Baja 1000 eight times, the most that anyone has ever won. That is the slowest class (36 hours-plus) and it uses almost all stock VW parts. If the design works for him it will work for us. Thanks for the photo :) Noted that they have to be modified. Quote My lowered shock looks quality, but I feel they are too stiff, maybe they end up being better at the front if I'd used them with the leaves solution mention at the top. I think they are too stiff for even that application. I know they are too stiff for a stock beetle--they will jar your teeth out. Reducing the spring rate will make it slightly better but the damper length is also an issue. They are just too short to offer good ride quality. And too stiff. Quote Bilsteins were mentioned in the qoute over here, any other quality options guys? Any adjustable? That could fine tune the ride? People love the Koni dampers but they are just an inexpensive twin-tube damper (think of a tiny cylinder within the damper tube and a bunch of oil that prevents heat from transferring efficiently). They use an antiquated base valve for compression damping. A base valve usually uses a series of ports with tiny check balls and springs. A hole will flow only a set rate of fluid before it hydrostatically locks. A stock damper is also a twin-tube design but the valve network is loose enough that they won't hydrostatically lock in most applications. The Koni 'adjusts' by covering the ports in the base valve. It stiffens the damper but that also increases the incidence of hydrostatic lock. The springs in the check balls also wear out in time. Also, a Koni doesn't benefit from high pressure to reduce cavitation and therefore heat. A Bilstein is a monotube design--the damper body is the cylinder itself. It uses over-sized ports and Belleville springs for damping. The springs deflect in a controlled manner as flow increases and will prevent the damper from hydrostatically locking. The Koni dampers have a very limited adjustment and once you set it the damping force remains the same for all occasions. The Bilstein dampers on the other hand constantly self adjust to match road conditions. I think you would be happier with the stock damper, though. It will give you the very best ride quality. A stiffer damper will not necessarily make a car handle any better but it will usually make it ride harsher. I have Bilsteins in all of my cars except my lowered Beetle. Thanks again for the detailed description, I've noted stock dampers as what I'll need, and then I also note the Bilsteins as an option to try out. I've got a low Mk1 Golf on KW v3 coilovers so I'm quite used to a harsh ride, but that isn't an option for the beetle this time around. Quote Any steering box mods from back in the day? Fill me in with everything you got on steering mods! Stock box installed and centered properly. Nothing more really. Quote What is a Cal-look norm from narrowing the beam? Stock? 2", 4"? 0". The narrowed-beam thing came about in the '90s when people started slamming cars. Some people have to narrow their beams about 2 inches to compensate for offset variations caused by aftermarket wheels, poorly designed disc brakes, and dropped spindles. A true traditional Cal Look car is rarely low enough to cause the tires to rub the fenders. I'll need a new box, the old one has alot of slack in it, and I can't get the screw on the top of the box (don't now the name for the screw) to compensate for it, and it looks a bit rough inside, so a new box will also add up in the list as things that will make my ride better. Stock is good, easier to get approved in the paper work for the beetle, and that helps out a lot if you get pulled over. Thanks a lot hotrodsurplus! Since spindles are mentioned. Drop spindles or not? And are alle spindles the same or is there someone who is better than the other? Regards Frank RT Title: Re: Link pin beam Post by: Jon on December 05, 2012, 04:39:47 am Any steering box mods from back in the day? Fill me in with everything you got on steering mods! Hi Frank, if you want to get rid of the bumpsteer you found, get rid of the caster shim, and install the steering box exactly as it sits on a stock beam. It's the slight rotation of the steeringbox ( in relation to the beam) that create the bumpsteer. Unless you have flipped the ends or something. Title: Re: Link pin beam Post by: Fankii-T on December 05, 2012, 09:04:14 am Any steering box mods from back in the day? Fill me in with everything you got on steering mods! Hi Frank, if you want to get rid of the bumpsteer you found, get rid of the caster shim, and install the steering box exactly as it sits on a stock beam. It's the slight rotation of the steeringbox ( in relation to the beam) that create the bumpsteer. Unless you have flipped the ends or something. Hi JHU. The issue with the bump steer and the ride quality of the setup I have no I don't care too much about. I'll buy new parts and sort out a brand new front setup from the smallest nut to the beam and brake setup, I'm tired of the whole slammed look and want to go more Cal-look inspired. But thanks for the reply. I thought the bump steer came from the car being relatively low, but it's the angle the caster shims is tilting the beam that's misalign the movement of the tie rods to the torsion arm, creating the bump steer? Or a combination? Since I'm planning out a Cal-look inspired build, it will be a slight drop in the front, should I still go with caster shims? And if I do that, I'll have to flip the tie rods ends upside down? To get the best ride out off it. Regards Frank RT Title: Re: Link pin beam Post by: Fankii-T on December 05, 2012, 09:15:56 am For the best ride off a slightly lowered front end, would a ball joint be better over a link pin beam? Just to clear that out.
I've heard link pin is better for a really low ride, but how does the two compare at just a slight drop? Title: Re: Link pin beam Post by: hotrodsurplus on December 05, 2012, 09:33:27 am Hi Frank, if you want to get rid of the bumpsteer you found, get rid of the caster shim, and install the steering box exactly as it sits on a stock beam. It's the slight rotation of the steeringbox ( in relation to the beam) that create the bumpsteer. Unless you have flipped the ends or something. Okay, please do not take this the wrong way but I do not think that the caster shims contribute to bump steer. Here are some things to ponder. 1) A caster shim is about 3/16-inch thick. The pitman arm is about 6 inches long, or about 20 percent longer than the distance between a kingpin beam's torsion tubes. So installing a caster shim would raise the inner tie rods by just shy of 1/4 inch. That is basically negligible. 2) Volkswagen sold caster shims at the parts counter specifically so customers could increase their cars' high-speed stability. Volkswagen would not have condoned much less sold a part if it greatly impaired the vehicle's safety. 3) Early steering-box clamps have a notch on each side that key on a slug welded to the beam. The notches are not in the same place. Turn the clamp one direction and it orients the steering box to fit on a Beetle; turn it the other direction and it orients the box to fit a Ghia. Also bear in mind that every manufacturer designs steering systems to toe in or toe out just a little bit when the suspension compresses. It is usually referred to as bump toe. That dynamic compensates the slip angle that the tires encounter in a corner by causing the tires to toe in or out when the suspension compresses and rebounds. Bear in mind that this is different than Ackerman, which is the dynamic that causes the front wheels to steer around the same axis in a turn. More than likely narrowing the beam has exaggerated this toe dynamic more than raising inner tie rods by less than 1/4-inch in relation to the beam. Even if the caster shims slightly negatively influenced the bump toe dynamic it would be an acceptable consequence if it fixed another more salient problem. The factory designed the chassis so the front suspension has 3 degrees 20' positive caster. Well Volkswagen also designed our cars to sit at about a one-degree rearward rake to achieve that. In other words, the nose sits higher than the tail. That doesn't look cool to us in Cal Look land so we modify our cars so they sit on about a 2-degree forward rake (the nose lower than the tail). The difference between those settings is about three degrees. That erases out the caster which wipes out the high-speed stability. I like to drive fast. I like stability. Therefore, I like caster. One set of caster shims increase the positive caster by about two degrees. That's almost perfect for a car that sits slightly nose down. I have combined two sets on a nose-down car for almost 25 years. That setup has more positive caster than stock. That also theoretically raises the inner tie-rod ends by half an inch in relation to the beam. I swear on my mother's one good eye that I do not encounter perceptible bump steer. And I am really sensitive to suspension flaws. I do honestly believe that narrowing the beam that much makes this car bump steer badly. I could be wrong but I do not believe that the caster shims have caused the bump-steer issue. As I mentioned, my suspensions do perceptibly bump steer but I also run a full-width beam. There is a remedy if the caster shims do in fact create a bump-steer situation. Simply heat the pitman arm and bend it back down by the amount the tie-rod ends raised up in relationship to the beam. Get the pitman to a dull cherry red in a narrow strip and use an adjustable wrench as a lever to bend the end of the arm down. Just do not try to force the arm if the metal is not hot enough. That will create tiny stress fractures along the surface and those fractures invite cracks. And again, please don't take this the wrong way. I respect your knowledge and experience and do not intend to insult you. Title: Re: Link pin beam Post by: Jon on December 05, 2012, 09:38:30 am I thought the bump steer came from the car being relatively low, but it's the angle the caster shims is tilting the beam that's misalign the movement of the tie rods to the torsion arm, creating the bump steer? Or a combination? The steering box is placed very accurately in VWs design to minimize bump steer, there is only one right place for it. That's why some stock beams have a little tab locating the steering gear. What I would do is to fit caster shims and forget about bump steer, or mount a universal joint were the hardy disk goes. In general, change nothing in the steering (lowering is fine), VW knew how to do it... In my eyes a linkpin always rides better than a balljoint, but requires more service than balljoints. [/quote] Title: Re: Link pin beam Post by: hotrodsurplus on December 05, 2012, 09:52:01 am Quote Great info again, thanks a lot for this! Just to get this right, remove both of the smallest leaves in each pack. The one facing the grub screw and the one farthest away from it, or try first by just pulling one in each pack? I typically begin with the narrower leaves first. They have the least spring rate so they will not make much of a difference. I think you may have the orientation of the grub screw and leaves mixed up. The grub screw exerts its force on the center leaves. The taper in the grub screw causes the middle leaves to move away from each other when you remove the half-width outer leaves. You may also have to remove a full-leaf from each pack. You may even have to remove two full-width leaves from each pack. Each application is different. Quote But also there is an issue about the EU as we call in in Norway, MOT in the UK (possible TUV in EU?), every second year we have to get the car inspected, a random workshop would maybe let it pass. But it's a good thing to have it written on paper that you are allowed to use a lowered front end if you get pulled over, and the CB puma beam has been classified as legal, but I think you have to tack weld the outer plate in place. So that you can't lower it more after the inspection. I want the car to be right this time, so I maybe have to live with avis design. Do the inspectors know exactly what a Puma beam looks like? Seems to me they wouldn't so as long as you showed them a receipt. You might have to exercise some Yankee Ingenuity. I can't imagine them making you tack weld the adjuster in place. How would you raise the car to tow it? Quote The beam I got now don't have the snubbers at all, and I've been thinking about what could happen if my shock bottom out. Hey wait a second. The inspectors will let THAT fly but not a type of adjuster? I hate regulation. It's retarded. Quote I've got a low Mk1 Golf on KW v3 coilovers so I'm quite used to a harsh ride, but that isn't an option for the beetle this time around. I'm with you brother. I used to put up with harsh ride if it made my cars handle well. But trying to make a car with a twin-trailing-arm front suspension, a swing-axle rear suspension, a rear engine, and tiny tires up front handle is like putting lipstick on a pig. I would rather my Volkswagens ride well and launch hard. Quote Stock is good, easier to get approved in the paper work for the beetle, and that helps out a lot if you get pulled over. I hear you. In my other life I build pre-war hot rods. There were few aftermarket parts beyond intake manifolds, camshafts, pistons, and engine adapters through the 1950s and 1960s. Hot rods are made of parts from various cars, a few aftermarket parts, and the rest gets made from plate stock, a torch, and a grinder. Quote Since spindles are mentioned. Drop spindles or not? And are alle spindles the same or is there someone who is better than the other? I like dropped spindles as long as they do not push out the wheel too far. I think a company in Germany was selling a forged, TUV-approved dropped spindle that pushed the wheel out only like 1/4-inch. That is another way to get the right stance and stock ride quality. I would still use adjusters, though. Only I would install them so they lower the car another inch or so and raise it up to stock for towing. Title: Re: Link pin beam Post by: hotrodsurplus on December 05, 2012, 10:01:42 am Quote The steering box is placed very accurately in VWs design to minimize bump steer, there is only one right place for it. That's why some stock beams have a little tab locating the steering gear. You're right that Volkswagen put a lot of effort into the steering system but there is more than one right place for it as I noted earlier. Here is a picture of the clamp that holds the steering box to the beam. The notch keys on the slug welded to the beam. Note that 13 is Beetle and 14 is Ghia. (http://images.thesamba.com/vw/classifieds/pix/4633511.jpg) Quote mount a universal joint were the hardy disk goes. That's a really good idea too. It will transmit a little more energy to the steering column but I think we can live with that. I'm sure you would have to modify the stub and column end but that would not be a problem either. Quote In my eyes a linkpin always rides better than a balljoint, but requires more service than balljoints. Stock for stock they really ride the same. Lowered with dropped spindles they ride the same. If you lower with adjusters or pull leaves, though, the kingpin rides waaaay better. The ball-joint suspension simply runs out of suspension travel if you lower it by more than an inch or so. Machts nichts, though; a ball-joint beam won't fit a kingpin frame head without a LOT of modification. Title: Re: Link pin beam Post by: Jon on December 05, 2012, 10:23:08 am Okay, please do not take this the wrong way but I do not think that the caster shims contribute to bump steer. Here are some things to ponder. Don't worry, I wont be offended, I have been discussing VW bump steer since 2002. And I LOVE to ponder :) I don't know if you have read it, but we had quite a long debate on bump steer in this thread http://cal-look.no/lounge/index.php/topic,18874.150.html It starts in reply 150 1) A caster shim is about 3/16-inch thick. The pitman arm is about 6 inches long, or about 20 percent longer than the distance between a kingpin beam's torsion tubes. So installing a caster shim would raise the inner tie rods by just shy of 1/4 inch. That is basically negligible. I agree, but it's the only "mistake" he has made, and if he feels he has to much bump steer, this is where he needs to dig in.2) Volkswagen sold caster shims at the parts counter specifically so customers could increase their cars' high-speed stability. Volkswagen would not have condoned much less sold a part if it greatly impaired the vehicle's safety. I don't think it greatly impairs the safety, and many small things can throw out the geometry built in to the suspension. I think VW knew that no matter what people did their solution was pretty great from the start, so they didn't worry to much.But, did they tell you to chisel of the slug when installing the caster shim? Or did they accept more resistance in the hardy disk? Do you know. 3) Early steering-box clamps have a notch on each side that key on a slug welded to the beam. The notches are not in the same place. Turn the clamp one direction and it orients the steering box to fit on a Beetle; turn it the other direction and it orients the box to fit a Ghia. Cool information, I didn't know about the Ghia, did the Ghia box use the sam pitman arm? Or spindles for that matter? Also bear in mind that every manufacturer designs steering systems to toe in or toe out just a little bit when the suspension compresses. It is usually referred to as bump toe. That dynamic compensates the slip angle that the tires encounter in a corner by causing the tires to toe in or out when the suspension compresses and rebounds. Bear in mind that this is different than Ackerman, which is the dynamic that causes the front wheels to steer around the same axis in a turn. More than likely narrowing the beam has exaggerated this toe dynamic more than raising inner tie rods by less than 1/4-inch in relation to the beam. To determine what VW built in regards to bump toe, we would either have to find a untouched bug or bus and measure it, or get access to the construction drawings of spindles and steering gear. The VW suspension/steering only moves in one plane, the narrowing is in a plane we have no movement in (when going straight). Even if the caster shims slightly negatively influenced the bump toe dynamic it would be an acceptable consequence if it fixed another more salient problem. I agree, have always used two sets of casters myself. There is a remedy if the caster shims do in fact create a bump-steer situation. Simply heat the pitman arm and bend it back down by the amount the tie-rod ends raised up in relationship to the beam. Get the pitman to a dull cherry red in a narrow strip and use an adjustable wrench as a lever to bend the end of the arm down. Just do not try to force the arm if the metal is not hot enough. That will create tiny stress fractures along the surface and those fractures invite cracks. And again, please don't take this the wrong way. I respect your knowledge and experience and do not intend to insult you. And I respect yours, but bear in mind, this is my second language :) Title: Re: Link pin beam Post by: hotrodsurplus on December 05, 2012, 11:19:35 am Quote Don't worry, I wont be offended, I have been discussing VW bump steer since 2002. And I LOVE to ponder :) Cool. 8) We are all amateur engineers to one degree or another. I have invested a lot by learning chassis and suspension dynamics. I hate mysteries and I always wondered why my cars behaved a certain way when I modified them. Quote I don't know if you have read it, but we had quite a long debate on bump steer in this thread http://cal-look.no/lounge/index.php/topic,18874.150.html It starts in reply 150 Good lord! That's a pretty bitchin' thread. I need to read that. Quote I don't think it greatly impairs the safety, and many small things can throw out the geometry built in to the suspension. I think VW knew that no matter what people did their solution was pretty great from the start, so they didn't worry to much. The design is remarkably consistent through the entire range for sure. Volkswagen limited the travel with the bump stop but I got more than 9 inches of front wheel travel in my wife's Baja by simply modifying the stop as noted earlier in this thread. And the bump toe is almost nil--maybe 3/16-inch at most from full rebound to full jounce. Incidentally that car has caster shims too even though it sits slightly nose high. As I said before, I love caster. Quote But, did they tell you to chisel of the slug when installing the caster shim? Or did they accept more resistance in the hardy disk? Do you know. No I do not know but I never thought of it until you just asked. My steering boxes key on the slug just as they did stock. Consider this. One set of caster shims alters the steering input shaft angle by only two degrees. That's nothing for a rag joint (your hardy disc) to accommodate. I would say the input shaft moved down less than 1/8-inch. So the relationship between my steering box has not changed. Therefore my cars' bump-steer properties are stock. Quote Cool information, I didn't know about the Ghia, did the Ghia box use the sam pitman arm? Or spindles for that matter? Yeah, that was one of the many subtle things I learned when I rebuilt steering boxes in a past life. If there was a difference in pitman arms it wasn't even close to visible. I always looked for variations so I could anticipate problems but I don't recall any differences in steering arms beyond the three prevailing styles. The worm/ball arm was unique unto itself. The arm for the kingpin worm/roller and ball joint worm/roller were functionally interchangeable from what I recall. The only difference was that the BJ arm had the stop tab on it. Quote To determine what VW built in regards to bump toe, we would either have to find a untouched bug or bus and measure it, or get access to the construction drawings of spindles and steering gear. I vote for the first solution. Much easier. I have a complete drum-drum beam in my yard. If I wasn't so damn busy I'd clamp it to my jig and cycle it. Quote The VW suspension/steering only moves in one plane, the narrowing is in a plane we have no movement in (when going straight). Yeah, I understand what you're saying. You have to examine the movement from the side as determined by the trailing arms and the tie rod and those dimensions don't change. The actual lengths of the tie rods differ from the actual length of the arms but the effective lengths are actually pretty close to identical. The angles are pretty close to identical too. That might not make much sense without a diagram. Anyway, I do know that Volkswagen did design some bump toe into the steering system. Theoretically altering the actual length of the various arms won't make any difference so long as the effective lengths remain the same and narrowing a beam and tie rods doesn't alter the effective length. But that is just theory and experience tells me that reality can really throw theory for a loop. Quote True you could do this, but wouldn't a heim joint in the the steering shaft be just as "easy" Well I think I have accidentally come to the conclusion that the rag/hardy joint can accommodate the tiny bit of misalignment so I do not know if I would go through the hassle of the U-joint. However, if given the option to bend the arm or install the joint I would bend the arm before you could say rosebud tip. That is a five-minute tweak versus a day worth of prep and fabrication. Plus a joint costs money and I am a cheap bastard. Plus I love heating and bending metal. Makes me feel powerful and stuff. Quote And I respect yours, but bear in mind, this is my second language :) I understand what you mean more than you would think I do. I'm married to a Swiss. Not a girl whose family came from Switzerland but an actual Swiss national (moved here in '01). I also learned to speak German when I was in grade school and high school (but since then I forgot more than I learned). So I understand from daily experience that things do not always translate perfectly. Therefore I pay extra attention to what I write and read. And for the record, your command of English is better than most native speakers' ability. Same thing for you, Frank. I cannot understand what some Americans write at all! ::) Title: Re: Link pin beam Post by: Jon on December 05, 2012, 13:35:35 pm I would say the input shaft moved down less than 1/8-inch. So the relationship between my steering box has not changed. Therefore my cars' bump-steer properties are stock. That's probably the best way to do it.Yeah, I understand what you're saying. You have to examine the movement from the side as determined by the trailing arms and the tie rod and those dimensions don't change. The actual lengths of the tie rods differ from the actual length of the arms but the effective lengths are actually pretty close to identical. The angles are pretty close to identical too. That might not make much sense without a diagram. To most it's hard even with a diagram, but you got it right of the bat. Impressed!Well I think I have accidentally come to the conclusion that the rag/hardy joint can accommodate the tiny bit of misalignment so I do not know if I would go through the hassle of the U-joint. However, if given the option to bend the arm or install the joint I would bend the arm before you could say rosebud tip. That is a five-minute tweak versus a day worth of prep and fabrication. Plus a joint costs money and I am a cheap bastard. Plus I love heating and bending metal. Makes me feel powerful and stuff. I get that, but I have since long stopped suggesting things of this nature. :) Even if I do things like that...Title: Re: Link pin beam Post by: Fankii-T on December 05, 2012, 16:16:15 pm Quote Great info again, thanks a lot for this! Just to get this right, remove both of the smallest leaves in each pack. The one facing the grub screw and the one farthest away from it, or try first by just pulling one in each pack? I typically begin with the narrower leaves first. They have the least spring rate so they will not make much of a difference. I think you may have the orientation of the grub screw and leaves mixed up. The grub screw exerts its force on the center leaves. The taper in the grub screw causes the middle leaves to move away from each other when you remove the half-width outer leaves. You may also have to remove a full-leaf from each pack. You may even have to remove two full-width leaves from each pack. Each application is different. Sorry I got it all mixed up in my head last night about the grub screw location. I will defently try this out. I went to look at what projects KCW had going on, on their forums last night and one of the busses they where working on thay had done this trick. Quote But also there is an issue about the EU as we call in in Norway, MOT in the UK (possible TUV in EU?), every second year we have to get the car inspected, a random workshop would maybe let it pass. But it's a good thing to have it written on paper that you are allowed to use a lowered front end if you get pulled over, and the CB puma beam has been classified as legal, but I think you have to tack weld the outer plate in place. So that you can't lower it more after the inspection. I want the car to be right this time, so I maybe have to live with avis design. Do the inspectors know exactly what a Puma beam looks like? Seems to me they wouldn't so as long as you showed them a receipt. You might have to exercise some Yankee Ingenuity. I can't imagine them making you tack weld the adjuster in place. How would you raise the car to tow it? I've never tried to get any thing legal with the old setup. But I want everything as legal as possible this time around. And from what I've been reading on forums, cars with Puma beams can get it on the vehicle registration paper as legal, but you have to tack weld it in place so you don't show them one setup, and then goes straight home and lower it more. This way if you get pulled over, they can't take you licens plate for running with a lowered front end. Quote The beam I got now don't have the snubbers at all, and I've been thinking about what could happen if my shock bottom out. Hey wait a second. The inspectors will let THAT fly but not a type of adjuster? I hate regulation. It's retarded. My setup wouldn't pass at all I think, but locking at the CB homepage I see that the narrowed puma don't have the snubbers. But the stock width have. I think both styles are legal. Quote Since spindles are mentioned. Drop spindles or not? And are alle spindles the same or is there someone who is better than the other? I like dropped spindles as long as they do not push out the wheel too far. I think a company in Germany was selling a forged, TUV-approved dropped spindle that pushed the wheel out only like 1/4-inch. That is another way to get the right stance and stock ride quality. I would still use adjusters, though. Only I would install them so they lower the car another inch or so and raise it up to stock for towing. Remember what company that could have been? Quote In my eyes a linkpin always rides better than a balljoint, but requires more service than balljoints. Stock for stock they really ride the same. Lowered with dropped spindles they ride the same. If you lower with adjusters or pull leaves, though, the kingpin rides waaaay better. The ball-joint suspension simply runs out of suspension travel if you lower it by more than an inch or so. Machts nichts, though; a ball-joint beam won't fit a kingpin frame head without a LOT of modification. Good, I like the link pin style, never tried out the ball joint. Know about the modifications, so I'd would have passed on it anyway. |