Well, I've decided the time has come to change my sbc powered teener to a better trans axle but in doing some research, I'm not clear on a few things...I've pretty much narrowed it down to either a Boxster or Cayman 6 speed.
While I know there are gads and gads of alternatives many of which the reader will no doubt recommend, for a variety of reason I'd rather we stay on point the original post. And while your guess's are fun to read, first hand experience is far more valuable.

First, I gather the Boxster S and Cayman Six speeds are essentially the same the Cayman having a higher gear set ratio.
True? False?

Renegade Hybrids stated the adapter they make for the Boxster is for the S six speed because their opinion is the five speed isn't robust enough to take the torque developed by a v-8.
True? False?

When it comes to the Boxster and the Cayman five speed, I've heard the Passat five speed is essentially the same but quite a bit less expensive.
True? False?

Would a sbc developing 400hp with something like 350 ft Lbs of torque have the ability to grenade the Boxster/Cayman (or Audi if true) five speed box if driven responsibly with frequent track days?
Yes, no?

And forgive this last question, the Audi FWD 01E trans axle six speed, what models used this trans axle and would it, could it, be used in the above noted spec engine without grenading?

Thank you in advance for your input and first hand experience.

Boxster & Cayman are essentially the same transmission with like a 0.01 difference in final ratio. Different model number too.

There are two styles on Boxster 6 speed. One has the traditional "Audi" shape bellhousing and one is round. The O1E has the traditional Audi style shape.

The O1E was never imported as a FWD transmission. Or the numbers are so low you will never find one in a car. They can be had cheap from Ebay.UK

I got my Boxster 6 speed (GETRAG) from the UK for under $1k shipped.

If I were you, look for an O1E or a TDI tranny from the UK. The TDI has taller gearing for the diesel motor. This would work better than the O1E or my GETRAG 6 speed.

I forget the exact year the round bellhousing is from but you would be buying a Porsche tranny and paying the price for it.

The Passat uses an Audi FWD tranny and so do many of the European TDI vehicles from VW, Audi, Scoda, etc.

A Passat tranny can be had for under $400 and is almost identical to the Boxster 5 speed. Since is is the traditional Audi shape, I bet it could even be fit to a 944 motor.

Thay all use the same or similar hydraulic slave cylinder. I use a Passat slave on both the 5 & 6 speed. Two reasons: Cheaper than the Porsche unit and 034 Motorsport sells a 3AN fitting adapter for it. When I swap trannies, I leave the slave in the car and swap it without bleeding.

You sir, are awesome :-)
Thank you so much for the valuable data!

I don't think there is a 5 speed to SBC adapter being made, so that point is mute. Also the consensus is that it's barely stronger that the 914 trans.

The 6 speed is beefy and the only one I would use in a track environment.

Kennedy Engineering makes the adapter, and I'm sure a few others do too but might just be for the LSx.

TDI 6-speed all the way, last time I priced it out I was at 4.5K. Realize this was a rebuilt trans, LSD installed 108mm flanges, tall gear set TDI FWD trans. Rare as hens teeth in the States, available in Europe. My supplier said lots of them have been beat on hard over there and due to age they are getting harder to find. He is a TDI performance supplier so his circles tend to trash stuff, with high HP and torque builds. His opinions might be a bit jaded because of that.

Without all the work going in, I would say the 2K is going to be the limit on a TDI FWD trans, best of luck with the search.

There is a very narrow band of Passats in the USA that also used the trans. The B5.5 in TDI form, rarer that any other Passat in the USA. People who purchased TDI B5.5 Passats with a proper third pedal, that is a very special person. And I would be one of them. I only see them pop up every now and again, most of them have high miles now.

Mike,

I bought my O1E from England some 14 years ago, and it is a TDI. From what I recall, and I used to be very familiar with the 012 and 01E codes, the TDI is an 01E and only differs with the ratios (perhaps this is what you mean?). Not all TDI's have the favorable ratios, and should always be verified against the code number. As a general rule of thumb, any 01E with the 3.89 1st gear, and/or the 4.11 R&P, are the ones to avoid. I have all the codes and ratios somewhere in my files. I'll stand corrected, as this is all from my poor memory.

The 5 speed 012 is reputed to be the weaker transaxle; I have no direct experience with it. The gears are narrower, and there is one less bearing in the countershaft. There are one or two rare codes of the 012 that have a taller R&P ratio. From memory, the code is DUK; don't recall the other.

I like your idea of leaving the slave in the car....it never occurred to me. Yeah, bleeding the slave is difficult. BTW, my slave is from and Audi 90. If I remember correctly, I used it because the hydraulic ratio was a better match for my Wilwood clutch master.

Andys

Wow.
My head is spinning. So many codes, flange sizes, strengths (01E v 012).
Are there any resources that are definitive?

Man, if you could share that list of codes and ratio's I would be ETERNALLY grateful. I've spent hours looking for a compilation of codes for naught :-(

Apparently Renegade makes the adapter for both the LS and the sbc/LT1 engines, but as you say, only for the six. That said, Mike brings up the point of the RWD diesels in the UK as having more robust 5 speeds and the DUK TDI as having a higher gear set that would be good for the 914 and track use (less sawing through the gears, v-8 remember).
Makes one wonder...

Look up Cracker. He has a thread or 2 about his car which is close to your goals.

Great timing on this thread since I have been trying to research the same upgrade for my SBC/901 combo. I may have misinterpreted some of the info about the 5 speeds above, but I called Kennedy Engineering Products today and asked what adapters they sell that would adapt a Boxster/Cayman/Audi trans to a SBC.

They make an adapter for the Boxster 5 speed and 6 speed. They are not interchangeable, but are the same price. I left my notes at work, but the adapter and flywheel are in the $850 neighborhood, and the clutch packages started at about the same price. A starter was $165.

They also make an adapter kit for the Audi 01E and 01X.

Edit - I didn't ask anything specific about the Cayman.

Cheers,
Josh

Good to know they do the 5 speed also. I've heard it's quite a bit less stout though.
And as I recall the Boxster and Cayman 6 speeds (and 5 I think) both share the same box but isn't the Cayman box geared higher?
Can anyone step in and verify that one?