Looking for info on the life expectancy of a 901 for a track only car. I have had no issues with my current 901 box behind my pumped 2.7 6 cyl. It is a short ratio box (flipped 5th) and has an intermediate plate and Guard 80% LSD.

I change the synchos every winter and go through the box.

Will I be able to get any type of longevity with a 3.2/3.4/3.6 bolted to it? I'm looking at building a 915 up for later, but I can have the engine done and back in the car before I will have the $/time to finish the 915.

The car is track and auto-x only. No street. We use first to get the car rolling and never use full throttle. We hammer 2nd through 5th.

What's the collective experence?

Thanks,

Bill P.

I have a short geared 901, 3.2 w 20/21 Web Cams, and usually run on Hoosiers. This is my second year owning the car, and Ive tracked it about 30 days over the past two years. Ive changed the gear oil twice, and havent found any silvery suprises in the old fluid. Th tranny shifts well still, all seems good.

The p/o did sell me a built spare trans with the car (one built, one in pieces), and mentioned that he trashed a tranny on occasion.. So far I havent had any problems though, perhaps the p/o and I have different driving styles

yeap, same here

I have no experience, collective or otherwise.

Should I ever bust up my 901....I do use full throttle in #1, I'm gonna talk to John at Otto's.

Thanks Tim,

I was hoping you'd answer as I remembered you saying before that you ran the 901. I've got a 2.7 with webcam 120/104 cams and the box seems to be doing fine.

What is you redline with your engine? Is it injected?

thanks,

Bill P.

Hi JP,

I've heard John from Otto's runs a pretty big HP motor through his 901.....maybe there are secrets to be learned....

or yearly rebuids of broken bits...

Bill P.

I redline at 6900, though my datalogs show 6600... I believe the MSD has a 7000 pill in it? ill have to check.

I have Webers on my 3.2, 40IDA's with 38mm chokes.. I dont remember the jet sizes though.

Some of you know that I am running a 901 short gear trans. with lsd, in my turbo 3.0 and am experiencing a little slip on boost and shifting through the gears, I have had 1st go on me before when I ran a built up type 4 ( 2.9 ) and would never consider a launch from 1st ever again. I am trying to decide whether to install a stage 3 kennedy pressure plate or keep the stage 2 and live with the slip thinking that it will be easier on the 901. I feel pretty confident that it will hold up to 300 to 350 easy on it horsepower, but I dont think it could handle being beat on. The positive side of the 901 is there still cheap and easy to come by, and I seem to always have an extra one laying around. The v8 guys may have the answers as they are throwing the big horsepower at it.

This is definitely a controversial topic but yes JW runs a bunch of 901's including his 3.0 and 3.8RSR/Motec 914-6 race cars. The trans in Rudy has not been rebuilt in 3-4 years and is a consistent TTOD winner with POC. Granted these are race cars that see limited actual run hours but what they do see is hot, stressful conditions (i.e. WOT 3.8L thru 12" slicks).

I am personally not a 915 conversion fan for feel/weight/cost reasons, but if you -really- need to handle torque then a 930 or even G50 is worth considering...that is if you are in the market for a >$10K trans+swap costs vs. 'just' a race 901 build. I'm not talking about a "boneyard swap" with a 915 Wevo or Vellios kit which is not an apples-to-apples comparison; the 901/914 trannies receive significant mods and assembly expertise and if the LSD, gearsets etc are done on a 915 on top of the conversion parts, then the added costs are substantial. The 901 is not cheap to do right, but still has a non-trivial cost advantage on top of its weight and light feel benefits. Of course is money is not a major concern then Hayden can hook you up with a hydraulic, flipped, gated, super-trick 915

250 hp 901 was just fine.

Up'ed to 300 hp - took teeth off the ring gear.

If you get 300 hp suggest the beefed-up intemediate plate and the beefed up Diff. Side Cover with .008/.010 preload.

It just take $$$ & time to make it work.

Ken

Hi Ken,

What size motor was your 901 hooked to? Glad to hear the consensus is that I can get away for awhile with the 901 while I save up $$$ for a 915.

I've built several configurations on my desktop dyno and I'm trying to understand the torque curves.

Thanks,

Bill P.

Bill,

It was a twin-plug 3.4 with Weber 46's. Ran I season at about 250hp then tweeked on the Dyno to 297hp.

Went to TH and blew the Diff on the 1st lap.

Saw the $ needed and retirement looming...

I love my stock 914-4.

Ken

Ken,

I would have loved a ride in your old car!

The $$$ thing really

Maybe I should sell the whole mess and take up mountain biking again...

Bill P.

....I think I have more money into my mountain bike and the damn thing won't go any further out my garage than my 914 will due to it needing work

I know the feeling...I've got a Specialized FSR Comp that I used to ride all the time. I haven't touched it in 3 years....

Of course....it really needs a bigger motor....and bigger brakes....and better shocks....

Hey...wait a minute...that sounds like my 914!

Bill P.