Just was wondering if anyone has put in another type of transmission with the stock motor still in place. I read all the time someone taking out the motor and puting in 350s and Subaru's and changing the trans at that point but i cant find anyone that just put in a different trans to the t4 motor. If anyone knows a link to a project like this that would be cool. I did a search but after reading many pages with no luck i thought i would stop and ask.

Question is why? Stock trans works fine with stock engine. 915 trans conversions have been done. What are you trying to gain?

There are ultimately only two reasons to put a different transaxle in the car.

1. You need a stronger one to handle lots of power.
2. You just want a cool project.

The 914/901 transaxle will handle up to (this is a GROSS generalization) approximately 300hp and ~250 ft/lbs of torque. Torque is what often kills the R&P assuming the lash and tooth-mesh pattern are correct. If those are off just running it will eventually kill it regardless of the powerplant.

If you want better performance at a certain RPM then you can get there by installing different gears (in your existing trans) in all but the 2nd gear position, which is fixed unless you install a 904/aftermarket mainshaft that can take different gear-pairs. Expensive but useful in certain types of racing.

There are many threads on this topic, but if you consider the 915, with the stock engine you'd want to find an early one with a 7:31 R&P, which is the same as the 914 you have now. But the gearing might still not be right. Again, very expensive, but a cool project.

What do I do?
I'm still running a 914 transaxle with a 3.6L six, and I've been doing that since 1999 both on the street and about 15 track events. I ran it with an E-spec 2.7L for years before that. My street driving is... spirited.

I've never lost a synchronizer, but have broken one pinion gear years ago. I have several 915's but simply haven't needed to install one of them because of any 914 trans unreliability.

But it's a VERY cool project , and I'll eventually do it for that purpose only.

Good Luck and just have fun with it... but mostly drive! Spend the money on driving experiences rather than hardware. Your biggest bang for the buck is driving and suspension. The drivetrain, once it's reliable, should be last on the list of expenses.

The factory put a 915 gearbox and a Type IV engine in the 912E.

They built a special mainshaft for the gearbox--a 915 shaft but with the 901-style end on it, so it would fit the stock 914 type clutch disk.

Good luck finding those parts, they only made 2099 of those cars in the first place. Parts can be quite hard to find.

You can do just about anything you want if you throw enough time and effort and $$$ at it. Boxster trans, Corvette trans, 924 trans, Bug trans, 930, whatever. But there isn't much reason to bother if you're running a Type IV motor.

--DD

Same here ...

PCAR916 is right on. I have been running a slight variation, using a 1970/71 911 gearbox with a flipped R/P against a 3.4 for 15 +years. You get a bigger clutch and keep the 901 gears.

Some day when my t4 needs gone through, i plan on putting in a Chevy small block. Thought about doing the trans thing first so i can be enjoying a cable shift and notchy feel. Its bad when i enjoy going through the gears on my jeep more than on my sports car. I have replaced all linkage and it shifts right but about every month i have to check all the screws cuz there is always one loose and thats enough to mess up the shifting. That gets old. So im thinking the Audi trans. I have read people puting them in this car behind v8s but not behind the t4.

How bout, has anyone put a cable shift to the 901?

McMark has been working on a setup for the 901. Not sure how far he got, send him a PM.

Not very far, but got a project that needs it coming up. so it'll be done in the next 6-8mo.

Actually, you have 2 projects needing it.

I have to think there will be quite a long line behind the first two projects that "need" it.

McMark, i will be watching your progress. Sounds good. Thanks to everyone for your response

For enough $$$ I might be willing to sell my 912E.

RenoRoger

The problem I have seen is the boxster transmission has the starter facing the wrong direction.
The swap you may want to consider, given your future plans, is the G50 911 transmission or a mendeola custom one...

The g50 seems to be about 3-5 k just for the tranny, then you need to flip the ring and pinion....all of that is very common and the reason the price seems to be so high is its a really strong tranny, and it works mid engine, so many of the race car kit cars have bought up all the spares...

That would be the path I would research if I was you, and you have time to shop for a deal...

Rich