Adding a 915 trans to a 6 conversion, There must be a better way Options

[mepstein]

I already have the parts. Early mag trans, cable shifter and PMS trans mount. I still need to rebuild the trans and flip the differential but that's in the works. Engine is a 3.2 that's getting rebuilt into a 260-280hp 3.4. I don't want a car that I have to baby 1st or start in second. The transmissions that Russo rebuilds shift like butter. I'll use a 4 pound lithium battery to save 30lbs and Ben will build me a lightweight exhaust to save some more weight on the tail end.

As the owner of two 914s with 915 conversions (one a 916) I would say DON"T DO IT!) the bulky shifting that 911s with 915s in them is accentuated, and the extra bit of weight makes the cars heavier feeling and more tail happy. 901 with the stronger intermediate plate works just fine.

Is there any reason I shouldn't consider working up a cable shifter instead of the traditional 916 shift linkage. The current 916 kit is $3-3250. Add in labor for machining and assembly and you're at $5k just to make the trans shift correctly. The suby guys are doing the shifting with $300 worth of cables and hardware. Am I missing something here?

[aturboman]

Good timing on this topic figured I'd share my 915-916 saga.

Picked up my completed trans Saturday after a 3+ year odyssey collecting parts and more importantly finding an experienced builder.

915 Mechanical speedo box, 7:31 Quiafe LSD, oil cooling and spray bar system, and Bott conversion kit, updated bearing saddle.

I'm going to a hydraulic clutch, with modified 1972 only 915/901 style shifter.

Here is my hydraulic pedal cluster using only factory Porsche parts including G50 pedal box as a basis

This is not an inexpensive endeavor to say the least but very close to the factory 916 set-up plus some performance / reliabilty updates.

[naro914]

901 with the stronger intermediate plate works just fine.

Not if your engine is 360+ hp...

[mepstein]

901 with the stronger intermediate plate works just fine.

Not if your engine is 360+ hp...

(IMG:style_emoticons/default/agree.gif) It doesn't solve the 1st gear issue. I want a 5 speed for this car, not a - baby first gear or slip the clutch and start in second - solution.

[Cairo94507]

Damn you guys! I have been longing for the 915 but keep telling myself the rebuilt (Dr. Evil) transaxle converted to a side-shifter with the gears recommended by the good doctor will be fine for me. I am not planning to drag race or launch the card hard. But now you have got me thinking......I will have to wait and see how my set-up works and drives. If not, I will be talking to Mark to see about sourcing parts.....but that would be down the road if needed and I would have to come up with some kind of excuse or the wife will probably kill me..... (IMG:style_emoticons/default/beerchug.gif) Yeah, I know, 1st World problems.... (IMG:style_emoticons/default/beerchug.gif)

[Dr Evil]

Damn you guys! I have been longing for the 915 but keep telling myself the rebuilt (Dr. Evil) transaxle converted to a side-shifter with the gears recommended by the good doctor will be fine for me. I am not planning to drag race or launch the card hard. But now you have got me thinking......I will have to wait and see how my set-up works and drives. If not, I will be talking to Mark to see about sourcing parts.....but that would be down the road if needed and I would have to come up with some kind of excuse or the wife will probably kill me..... (IMG:style_emoticons/default/beerchug.gif) Yeah, I know, 1st World problems.... (IMG:style_emoticons/default/beerchug.gif)

Dont do the 915 until you blow up that 901 (IMG:style_emoticons/default/wink.gif) That should buy you plenty of time (IMG:style_emoticons/default/biggrin.gif)

[mepstein]

Damn you guys! I have been longing for the 915 but keep telling myself the rebuilt (Dr. Evil) transaxle converted to a side-shifter with the gears recommended by the good doctor will be fine for me. I am not planning to drag race or launch the card hard. But now you have got me thinking......I will have to wait and see how my set-up works and drives. If not, I will be talking to Mark to see about sourcing parts.....but that would be down the road if needed and I would have to come up with some kind of excuse or the wife will probably kill me..... (IMG:style_emoticons/default/beerchug.gif) Yeah, I know, 1st World problems.... (IMG:style_emoticons/default/beerchug.gif)

Dont do the 915 until you blow up that 901 (IMG:style_emoticons/default/wink.gif) That should buy you plenty of time (IMG:style_emoticons/default/biggrin.gif)

(IMG:style_emoticons/default/agree.gif) I'm sure you will drive your can enthusiastically but not overly aggressive and it will be fine. Bob Saville drives Huey with a 3.2 and 914 trans. I just want what I want for my flared car even if it doesn't make proper sense. I also paid $500 in parts trade for the trans, the rebuild will be the wholesale cost of a couple bearings and even the cable shifter was just $200. I need some machining and a sleeve where the main bearing is loose in the trans case but our shop owner just bought a machine shop nearby. It's a different ball game when you pay real dollars for this stuff. Like Steve said, plan on around $10K. And then do you want to add more weight on a nice light narrow body car.

[naro914]

^^ Like Mark said... our car Huey has a stock 3.2 engine and a stock 901 trans - been fine for years including hillclimbs, a race at Road America, autocrosses, spirited drives, etc.

Papa Smurf has the 915, totally re-geared with a pretty stout LSD (dont remember the brand) and modified Vellios conversion. Peter Dawe is a master at setting these up and has a few of them if anyone is interested. He has a trans housing with access holes so he can adjust the mechanisms while its actually in the car and you're actually shifting (on the lift) and he can see where the adjustments need to be made. Then once he's happy, it goes back into the standard housing and tested again. Ours shifts great.

[John]

I hope this thread is still active and not a dead one from 3 years ago. If it is dead, I apologize.

I have to disagree with the hard shifting of a 915 with a Vellios kit. Granted, I have made several "adjustments" over the years to the rough kit, but my track car shifts just as well as my street car with a nicely built 901/914 trans with a stronger intermediate plate. Both run behind 3.2 engines, but the 901 simply can't handle the torque and sticky tires the track car has due to some rough race tracks. The 901 doesn't like rapid changes in torque (slipping or bouncing rear wheels under power).

The 915 so far, seems to hold up better under those conditions.

The 915, however, is NOT bullet-proof. The first Ring/Pinion went south before I bought the tools to set up pinion depth myself. Since then, it has held up well.

That being said, the Vellios kit needs some tweaking in order to make it function as it should (likely most "kits" would, but I have no experience with others).

An alternative that I saw many years ago was from some folks from the Phoenix area used to have an external shift linkage to shift a 915. I have some pictures of such a car.

[dr914@autoatlanta.com]

when we used the vellios kit before it passed into history we had to machine some of the linkage to get it to shift smoothly, as smoothly as it was capable of