The Cal-look Lounge

Well I'm finally biting the bullet and putting together a list of parts for a decently built swingaxle tranny for my '67. I'm going to be going with stock 1st-4th on a 4.37 R&P, I already have a super diff and an H.D. Side cover. I'm already planning on a pair of good forged axles, but beyond that I'm at a bit of a loss for what else I'm going to really need. Keep in mind, this is on a bit of a budget so Rhino cases and Quaife diffs are out the window. It's going into my street/bracket racing car that runs high 14s on radials, but we might be trying a pair of slicks on it once or twice, just to see if a 1914 can pull the front wheels off the ground  ;D any advice is appreciated, thanks!

Do you have a mid mount and traction bar?

Forgot to mention those... yeah, I have those.

A Super Beetle 1st gear is something that often seems done.

I've definitely heard it mentioned before but I haven't ever heard an explanation as to why it's done.

Yes its a good upgrade, later 3.78 1st is a lot stronger than earlier 3.80 1st

Good to know, thanks!

For a budget box a IRS double side cover box converted to swingaxle with the superdiff would be a good start

I mean, I'm not entirely broke, and a super diff/side cover is what I've been running for a while, but I know it's on borrowed time, plus I want to change up the gearing in my car. Mostly I'd like to know where I could get my hands on a set of steel shift forks and similar things, plus any extra little tricks to keep it together a little tighter. The big purchase here is going to be a set of good axles, as well as the tranny itself. The Berg posi-shim kit is definitely interesting, would you recommend it?

Be aware of superdiffs mashing up side gears and fulcrums due to poor oiling. I only got 300 miles from the previous one in my trans before it gubbed everything.

Good to know! I haven't had any issues with mine over 2 years, so I think it should be good! Are there any modifications to be done to them to keep that from happening?

To make a SD live, drill lots of oiling holes in it.
I drill at least four 6mm radial holes for each side gear.
Almost all SDs have a paddle sticking up in the casting so that when you drill beside it, oil can be directed inside it.  Most drill it to 1/2" and leave it as a round hole.  Better is to increase it, and use your die grinder to turn the paddle into a scoop.

To help your fulcrums live, drill holes in the side covers to allow oil to get to the outside of the diff's bearings.

Don't do it, it doesn't work.  The shims quickly get chewed up when driven on the street.

Ah noisy diff...

What's the recommended oil to use?

I have EP90 in my box and despite a rebuild a coupe of thousand miles ago, the classic Cal Look whine mentioned on umpteen threads  on here is ever present; it never really went away.

I read a thread a while back, it also referenced a you tube vid, on how to machine a superdiff to get better oil flow.

In my case, I was thinking of trying semi synthetic gear oil to see if would help quieten things down a bit.

Better sound proofing is a job for this winter, but a traction bar and mid mount are great ways to transmit noise into the cab.

Back to the subject, you might want to consider a 3.88 R&P if you want to raise the gearing. I have a 3.44 which is great for a street car, but might be a bit high for the track.

Do you mean is this a special one or just normal IRS box?

Regular earlier IRS box is double side cover so can be converted to swingaxle, later IRS is single side cover so cant but for me they are both a lot stronger than pre IRS swingaxle boxes btu still need the superdiff added.

Short journeys don't seem to damage the superdiffs where stopping allows the oil to get back inside everything but long motorway/freeway journeys over 100miles or so without stopping seem to mess them up pretty quick.

What's the alternative, save up for a Quaife? I hope to continue to be able to drive mine long distances.

I rekn the most important part to keep your diff from popping is keep the thing steady and stop any axle-tramp.
The bracing is more important than the internals on your average (a bit like yours) streeter.

I'm not anywhere near an expert, but the builders that are told me what I needed to get 1000kg off the line and down to flat 13s without breaking (assuming it stays straight).
Superdiff, HD mainshaft, steel forks, big bearings, oiling attention, rear bearing plate........and careful assembly.

There are a few gearbox gurus on here that could probably even give you part numbers perhaps for where you are, or a link if that's allowed maybe?

Also don't forget that slicks will really hit them hard, but run sticky radials (Advans, Nittos, fast roundy car stuff) and give up a tenth in the 60ft and it will last much much longer.

Oh sorry forgot about that single sided IRS box... I know what you mean now.
Thanks.

I'm not entirely sure what it looks like inside, as the last time I had it apart was 2 years ago, but my S.D. seems to be doing just fine with some lightly-to-moderately abusive driving and more than my fair share of 100+ mile drives. The plan at the moment is to use an S.D./ side cover combo that a friend has set aside and then he'll take the stuff that's been in my car. I'll definitely make sure to take it all apart before we do anything stupid!

That all looks to be about what I'm hoping to get into my 'box. I have a guy who is going to build the thing for me, so I'll make sure to specify a few of those things. As far as the slicks go, the same friend with the extra diff/side cover has said he'd let me borrow the Centerlines/cheaters off the back of his racecar one of these days, just to see what my 1914 can really do! Most of the time I'm just going to be running my regular 185/65 radials since I don't have enough money/wheels to set aside for some fancy tires, but maybe someday!

What about the bus box option? Get out the angle grinder and stuff one of those in your car. Free or cheap and easy to find and replace.
Is there a down side besides the extra installation work?

Mostly I don't think it'd really be worth the effort. Plus, I like keeping my '67 a swingaxle car that could be reverted to fairly stock without a horrendous amount of work. Since it's my only bug for now, I'd rather keep it more street-oriented than build an all-out racer out of it. Maybe someday I'll have my drag car with license plates, but for now I'll be happy with a street car that can bloody the noses of the V8 guys at the track in the summer.

They are now fetching good money and ratios are really bad, also unless you do a bug to bus conversion type intermediate housing they shift really poorly

It was Dawn Simas, who had the late Ray Vallero build her gearbox for her '63. The YouTube videos are very useful - the photos went missing in the photobucket mess up - and they are what I followed when I put a superdiff in my car.

I watched a couple of those videos earlier today, I'm surprised that superdiffs aren't better set-up for oiling! I'm curious to see what mine looks like when it finally comes out, it's been in and trouble-free for over two years of some not-very-nice driving! I suppose the one that's going in will probably be getting a few extra holes drilled, just to be safe.

When you say trouble free, is it quiet? Or should I say how quiet is it?

Well, I haven't noticed anything out of the ordinary, as far as noise goes, and the last time I changed the fluid, nothing seemed off with that either.

The whine on my 'box is obvious and it is definitely speed related, you mostly hear it in 3rd and 4th, it could be the R&P I guess, but I'm more inclined to point the finger at the SD; given the known oiling issues.

Before it went away for a rebuild it also whined, but the cruncher was the R&P had two chipped teeth, at the time the 'box builder declared that while the box was open the SD was also in need of replacing. The failed R&P had a very different noise, more of a knock.

The 'box was built up by a reputable chap, who came well recommended, but I doubt he machined the SD, cos I didn't ask him too, and I can't imagine he would do work extra without getting paid for it; he has a business to run after all.

Box has done a couple of thousand miles with plenty of freeway/motorway work.

A superdiff is a consumable.  Just like gear oil.  Every time you open the trans, you throw away the SD.  Do not buy a used one at a swap meet, they are all junk.

Your noisy gearbox in 3rd and 4th, is probably due to a bad main shaft ball bearing.  This is the bearing adjacent to 4th gear, and while in 4th, the greatest radial load is applied to this bearing. First gear is at the opposite end of the main shaft, so the load applied to the MS Ball bearing is nil while in 1st gear.

It's too bad Ray Vallero's videos are so short:

https://www.youtube.com/watch?v=tLDPyEDkfMM
https://www.youtube.com/watch?v=kjqZtcnuSvs
https://www.youtube.com/watch?v=5ZhN6AgJHW8
https://www.youtube.com/watch?v=nEtk0ZKa6VQ
https://www.youtube.com/watch?v=FnBADj2eiPI
https://www.youtube.com/watch?v=PHYGqcMx1qA
https://www.youtube.com/watch?v=iFdVDRmpwdM

It seems every bug I?ve had has some of that whine in 3rd and 4th. My turbo had it bad with its original 68 trans. Then it was obviously there with a new pro street Rancho from new and it gradually lessened and is now minimal. I have another low miles 68 original bug that never had its engine out until I got it. I changed the trans oil. You guessed it, there is a slight whine in 3rd and 4th too. Harder mounts make it more obvious.

I had the main shaft bored and sleeved when it was rebuilt as it was badly worn, it was bad enough for a new case but mine's been gusseted and this was a cheaper option than gussetting a decent second hand case. I assume it had a new race, but I'm no 'box expert. Perhaps, it has a tapered race, don't the Rancho's have that?

Seems to me there?s a dual taper roller bearing upgrade to replace the ball bearing. My 65 had its original stock box rebuilt back in 99 and it got one of those roller bearings. It also got the Berg poor mans posi shims. That?s one trans that is completely noise free. Too bad it?s leaked forever oh well.  :o

Scat has listed on their website a "Heavy Duty Snap Ring Diff," but without any pictures I can't tell if this is any different from a "Super Diff" sold by anyone else. It sure sounds like the same thing though.

Same thing.  In fact, the castings of most brands look suspiciously similar.....   (Except McKenzies)
While I think all superdiffs are inferior to the stock diff, at least the Scat diff is machined correctly.  The diameters are right, and they have the oil hole in front of the paddle.

Oil hole by the paddle:
I could never understand why some diff sellers don't put the hole in.  When I asked one, he said it goes on the other side for mid engine sandrails.  Makes sense, right?  Wrong!  The drive side of the ring gear tooth is always the drive side.  IOW, the diff always turns the same way relative to the oil.

Interesting... Aside from the aformentioned oiling and machining issues, what makes you say that a superdiff is inferior to a stock one? My experience thus far has been pretty positive, and considering that I blew up two stock diffs withing six months, I'd have to say that mine has held up pretty well thus far! While I don't doubt you saying that they're a consumable, I'd like to know what else there is wrong with them.

It's the type of cast iron used in the aftermarket SDs, it's no where near as good as what VW used 50 years ago.  If you could get a SD that's the same type of iron as stock, then you'd have something GOOD!

When you blew up two stock diffs, was it the diff housing, or the gears?

In my sons turbo car we have an old SD , has a red oxide coating on it and screw in side gear retainers , never had a problem in 20 years of using it . If it has problems with side gears or spider gears I would look at my clutch and rear suspension very closely. Wheel hop will destroy a transmission very quickly .  I like the early cases , the ones that have a pinion bearing plate with 4 bolts , replace that plate with a C/Moly unit . The later cases have a pinion spanner nut instead of the plate , they may be great but the super fine threads are not superior IMHO . Gusseting a early stock case on the clutch side on the bottom makes a stock case superior to a unmodified Rhino case and that is what I am using on my 450 plus HP turbo car along with a stock 3.88 R/P . The earlier 3.80 first gear was very weak and the later 3.78/2.05 mainshaft will hold up extremely well if your clutch package has just a little slippage in it . Nothing is unbreakable if you try hard enough but with a little common sense you can have a lot of fun without spending a fortune. 

To be entirely fair, it was the gears. I could see the iron being lower quality, VW almost had a fetish for using really good metals in their cars. But yeah, I took more than a few teeth off of the gears in two stock diffs.

Do you know if they were 11/17 gears or 10/15 gears?
I know one guy who claims that two 10 tooth spiders in a stock diff are stronger than four 11 tooth spiders in a SD.

Going from 11/17 gears to 10/15 is like going from a 10 tooth first gear to a 9 tooth first as far as strength goes.

I think they're 11/17s, but I'm not 100% sure as the last time I had it apart was well over 2 years ago. One thing I'm sure of is that I didn't change them when I put the S.D. in it, so I either have been really lucky or they're possibly 10-tooth ones.

When you break some of the gear teeth in a diff, all of the gears should be discarded.

Well I've decided to just go with a Super Street Plus swingaxle transmission from KCR, substituting a 4.37 R&P for the standard 4.12 and buying some good H. D. forged axles. I'm definitely looking forward to having a proper gearbox in my car instead of a ticking bomb!

Andrew - you have PM

Rancho Pro Comp, 400+ trips down the 1/4-mile, GL5 synthetic, no issues yet, except the typical howling in 4th gear during deceleration