Built Tranny necessities

[andrewlandon67]

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   any advice is appreciated, thanks!

[Andrew]

Do you have a mid mount and traction bar?

[andrewlandon67]

Do you have a mid mount and traction bar?

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

[Andrew]

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

[andrewlandon67]

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.

[richie]

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

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

[andrewlandon67]

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

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

Good to know, thanks!

[richie]

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

[andrewlandon67]

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?

[Richierich56]

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.

[andrewlandon67]

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?

[Bruce]

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.

The Berg posi-shim kit is definitely interesting, would you recommend it?

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

[Andrew]

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.

[Eddie DVK]

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

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

[richie]

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

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.

[Andrew]

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.

[modnrod]

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.

[Eddie DVK]

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

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.

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

[andrewlandon67]

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'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!

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.

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!

[Martin S.]

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?

[andrewlandon67]

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.

[richie]

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?

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

[Neil Davies]

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.

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.

[andrewlandon67]

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.

[Andrew]

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

[andrewlandon67]

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.

[Andrew]

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.

[Bruce]

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

[Martin S.]

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.

[Andrew]

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.

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?