Transmission questions

Hi,

I like to build my first Transaxle for practice. I thought I have a 412 but they are all 437. This trans will only be for getting a little bit into driving the car, suspension adjustment...

I do have a single and a double side cover Trans. Both are AM. My friends love the single side cover for drag racing and formular V. They said the case is stronger. So what do you think: is this one with a HD-side cover and a superdiff with the 437 o.k. for the first tests or will it be a stupid idea?

Single side cover cases (with dual ring side covers) are strong and typically come with 3.88 inside and 3.78 (9 teeth on mainshaft) first gear, which can also use an 091 1st gear idler with some modification.

Late dual side cover case without the second ring on the side cover are typically 4.12 inside and have the weaker 3.80 1st gear (10 teeth on mainshaft)

You're saying you'll use a dual side cover with a 4.37 for testing? sure, go for it, but I'm wondering why build it, just run the one you have for awhile, it will die soon enough!

To race in SNORE/MORE you'll need the 4.12 though, and you'll need about $1000 tools to do a proper race-spec rebuild so it may not be worth the struggle, I'm having second thoughts now since they take me so long, but Scott @ Metalcraft Motorsports is the best, maybe he will chime in here.

We do race in Central Europe so I don't have to follow the rule books of SNORE etc. We do not have a Class 11 but I like to race a car like that. The reason is I race a car now which is worth about 25.000 USD and in my Class there are cars like your Class 1 and Ultra 4x4 with teams having big budget. Most of the time they are behind me in the end. So now there is the plan to go with a Class 11 . This should be a "low budget" project, but we take it seriously in the competition.

So we like to have a strong trans and if a better ratio for example can be done for our "Class 11" car, we can do it. As we do still have the other car, this should not explode in budget.

I would love to go to Scott at Metalcraft, but this is about 10.000km one way...

Call it look alike Class 11 or whatever. In the end we do serious racing with it. So I hope we get good infos about how to build a trans we can use. Right now we have a stock dual side cover trans (AM) and a single side cover (AM). The AM code says they should be 4.37 ratio. Maybe this one is not available in the US or Mexico.

this is the one we are talking about:



so is this side cover stronger? Is there no need for a HD side cover?

Use the single left side cover case, with hardened keys, 4.12 ring and pinion, heavy duty diff, hd side cover, type 2 output flanges, and since you can do anything you want run close ratio gears as well. I'd buy as many waddle gears as you can since they will last forever inside a class 11 car, which it sounds like you guys are running.

If you want to use a stock VW trans without having to do any real modifications run an 002 or 091 with type 2 output flanges and close 3rd and 4th gears. this would be a really fun transmission to run in a class 11 car. Not legal here in the states, but you guys don't have to follow the rules we do here so have fun with it.

A 4.37 R/P is weaker than the 4.12, 3.88 being the strongest. Close ratio 3rd/4th gear sets are reletively inexpensive as opposed to running a 4.37 R/P for closer shifting.

Tapeworm wrote: If you want to use a stock VW trans without having to do any real modifications run an 002 or 091 with type 2 output flanges and close 3rd and 4th gears.

so I'll better go for this one:



It's also in my garage. I know it is the nose/side shift and a nose shift would be better, but those are almost impossible to get here. So I have to convert it to nose shift or develop my own shift mechanism.

It is a DH (5.34 ratio). Do you think I still have to go for closer 3rd and 4th?

What does "no real modifications" mean?

As far as the trans goes, you can run all stock internals except close 3rd and 4th gears with an 002 or 091 in an 11 car. You would have to fab in the trans to the car which isn't too much work, but it does have to be done right. You either have to run a 10 degree kit which makes stuff really, really tight in the engine compartment, or notch the frame horns to clear the CV's.

It sounds like you want to stick closer to the class 11 trans, so go with the single side cover case and convert it to the straight shift with some american parts if you can.

Here are the SNORE rules for you:
Type 1 bug 4 speed transaxle only. Heavy duty side plate and differential
allowed. 8.33 (4.12) ring and pinion only. Stock VW 1st, 2nd, 3rd, 4th gears only, no close ratio gears allowed. Axle over tubes are not allowed. Other internal modifications are optional. Rear transaxle mounts may be supported by a maximum of two vertical straps of .025” x 1” dimension. Adjustable straps are optional. Any gearshift lever allowed. Shift tube must be inside tunnel. Any type 1, 2 or181 stub axle and any VW cv joint. Oversize bolts ok.

An HD side cover, HD diff, Close ratio 3rd and 4th with hardened keys and internals will do you good.

It may be expensive, but here is Weddle's website for all the aftermarket gears for the trans you could desire.
weddleindustries.com

Tapeworm wrote: As far as the trans goes, you can run all stock internals except close 3rd and 4th gears with an 002 or 091 in an 11 car. You would have to fab in the trans to the car which isn't too much work, but it does have to be done right. You either have to run a 10 degree kit which makes stuff really, really tight in the engine compartment, or notch the frame horns to clear the CV's.

It sounds like you want to stick closer to the class 11 trans, so go with the single side cover case and convert it to the straight shift with some american parts if you can.

An HD side cover, HD diff, Close ratio 3rd and 4th with hardened keys and internals will do you good.

A 10 degree kit and notching the framehorns would be a Pain In The A$$ on a full bodied car with full engine seals and tin.

The single side cover is a normal shift in the pic, the 2nd transmission looks like an 094 to me. With a 5.34 R&P in that box you do not need close ratio 3rd/4th for class 11 sized tires. Check out the gear ratio calculator on weddleindustries.com The downside of the 094 is that it has the fine tooth 3rd/4th in there so those would be prone to breaking more than anything I would guess, haven't raced 091/094 that weren't fully built ($5K parts everything inside is replaced)

For the single side cover you do not use hardened keys, your 3/4 slider hub would be splined onto the mainshaft since it has a late model super beetle mainshaft (3.78 first gear ratio), you also won't need a hardened key for 4th gear since it's splined onto the pinion of most 4.12 R&Ps especially Ks and Os.

A decent class 11 transmission can be built from the single side cover case, you may be able to sell the 3.88 inside of it for about $200 pretty easily to offset the core price of the transmission.

While most believe the single side cover case is stronger, the pinion bearing is prone to wear and that ruins your day quickly. Scott is miles ahead and has come up with a winner combo, remember VW did upgrades based on the trans going 200,000 miles not a 250.

bugged wrote: While most believe the single side cover case is stronger, the pinion bearing is prone to wear and that ruins your day quickly. Scott is miles ahead and has come up with a winner combo, remember VW did upgrades based on the trans going 200,000 miles not a 250.

True story, I have used the SSC case but that large pinion nut is lame overall but can work. If you have more $ then get a rhino aluminum case, heavier and denser, that case will not wear the pinion bearing bore as quickly and has the 4 bolts instead of the one big nut.

I would love to spend 4000 or more bucks for a trans. Because this would live for ever. Reason: I would have no money for a motor.

There are so many things I have to buy and have to keep care not to create a dead project.

So for the beginning I am looking for an economic solution.

I have to add up later on. First it needs to get rollin at all.

A decent transmission can be put together for less than $1K. I have won several races using a transmission with nothing more than a super diff. Robert makes a good point though, the big pinion nut (091 style) is a pain in the arse and the pinion bore gets loose awefully quickly.