901 power limitations Options

[-JR-]

I've been planning components for a 3.2 914-6 car. I had been planning on using a G50 transmission but now from a reliable Porsche enthusiast, who also races in SCCA, that a 901 would be a better route. Primarilly that it "should" take the power and it's a significant weight saving over the G50.

I want to run a stock 3.2-6 which I believe turns out around 220HP and about the same for torque.

I've seen offical Porsche litterature which stated that a 901 transmission is good for up to 148FT/P of torque but they have been used up to 235 in race applications with dimished life spans.


This car is being built primarilly to be an auto-X machine, but it will also be used for PCA touring events. So I need a trans that can take heavy punishment over short auto-X stints.

Has anyone on the list had experience with this?

Thanks!

[East coaster]

See this thread......... tranny thread

[Aaron Cox]

915.....

a g50 hangs out the rear i hear...

[Type 4 Unleashed]

G50, I've read several times how they stick out the rear, is that because the bell housing is longer than the 915 and 930? And that is due, from what I understand, is some type of vibration damping rubber hub.

To, cut this short, I read an article where this guy wanted to use the G50, for the gear ratios, and he didn't want to use the G50 clutch, plate, and hub, he went with the, I believe 930 clutch package, and machined down the bell housing to the 930 & 915 length. And didn't notice any additional vibration with the hub removed . With the bell housing now machined, wouldn't a G50 now sit in the same location as a 930 or 915? Anyone aware of this prcedure? Or this article I'am talking about?

Richard

[-JR-]

Good reading on that trany thread. I'd be interested to know if JOHNMAN
is running a stock 3.2 or if it's been done up any for his race application.

I'm most worried about grenading first gear when I'm trying to launch it off the line with the auto-X stickies on.

That's also the first I've heard about length issues with mounting a G50 in a 914. But that's not to say I'm no expert on this topic by any means. That's good to know, especially if I'm considering that trans.

The 915 5-spd (apparently it came in both 4 and 5spd) trans was also in my considerations. Apparently it's a very tough transmission, right up there with the G50 except no 6th gear.

I have a line on a G50 trans from a C4 locally, but if the C2 version is long to begin with, I'd probably never get a C4 one to fit with the extra drive housing on it!

James

[Series9]

I'm most worried about grenading first gear when I'm trying to launch it off the line with the auto-X stickies on.

And that is how it will likely fail.

At 220hp, you're at the 901 transmission's limit and well past the first gear's limit.

Getting an appropriate tranny in the car is an expensive proposition. I have almost $5k in my Vellios-converted 915 limited slip tranny, but if you want to enjoy the car, it needs to be done.