Is the porsche 915 tranmission a bolt in replacement for the porsche 901?
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Is the porsche 915 tranmission a bolt in replacement for the porsche 901?
No. The 915 uses a very different clutch cable arrangement than the 901.
The splines on the input shaft are different (different clutch).
The bell-housings are the same, starters are the same. I can't remember if the transmission mounts are the same. I'm assuming you are talking about a 901 out of a 911. A 901 out of a 914 definately has different mounts than a 915.
angela
The splines on the input shaft are different (different clutch).
The bell-housings are the same, starters are the same. I can't remember if the transmission mounts are the same. I'm assuming you are talking about a 901 out of a 911. A 901 out of a 914 definately has different mounts than a 915.
angela
I vote: NO.
George chose the 901 because of its shift pattern I'm sure. (he would have gotten the best..IHO) The 901 is set up with 1st being out of the H because the thinking was that you only use 1st to get under way and that most of the time drivers would be in 2nd to 5th. I think many people like the shift pattern of the 901 versus the 915...I know I do.
The 915 is not without its problems too. I think it was blamed (or the drivers) for many a blown engine as its apparently relatively easy to select a lower gear when downshifting and then reving the engine beyond its limits. Can't recall the specifics but someone else here knows I'm sure.
If you check you will notice there are lots of "fixes" out there for the 915 to try and eliminate this. They range up to a grand I think for internal gates and fancy shifters. You won't see that advertised for a 901 trans. Perhaps a fancier shifter with perhaps stronger detent springs but I haven't seen the aftermarket "fixes" for a 901 like a 915. Maybe there is just a bigger market or maybe its a bigger problem. Anyone else know?
The 915 is not without its problems too. I think it was blamed (or the drivers) for many a blown engine as its apparently relatively easy to select a lower gear when downshifting and then reving the engine beyond its limits. Can't recall the specifics but someone else here knows I'm sure.
If you check you will notice there are lots of "fixes" out there for the 915 to try and eliminate this. They range up to a grand I think for internal gates and fancy shifters. You won't see that advertised for a 901 trans. Perhaps a fancier shifter with perhaps stronger detent springs but I haven't seen the aftermarket "fixes" for a 901 like a 915. Maybe there is just a bigger market or maybe its a bigger problem. Anyone else know?
There is a fair amount of stuff available for a 901 including improved linkages, better shift couplers, the kit to correct the simplified differential, stronger side cover plates etc.
The 915 was always a stronger transmission. So if you were going to build a high hp engine or very torquey engine, you went with a 915. First is unsupported in the 901, the 915 is much improved in this area. As far as the 901, 2nd thru 5th are are pretty darn strong.
The 915 is also significantly heavier and larger than the 901. George chose well. The dogleg shift pattern is uber-cool vintage racer style. The transmission is light and well suited to that car.
I've spent a fair amount of time between 901 and 915 transmissions. Honestly, they are both pretty darn vague in the shift pattern. There is no distinct gated feel as there is with other transmissions including muncies, saginaws, even alot of cable shifted FWD cars have more precise shift action.
I suspect the transmission in question may have a linkage adjustment issue. Beyond that, these transmissions greatly reward light handed drivers who practice. I've been teaching myself to play the guitar. I think the guitar is easier than than my initial learning curve on a 901 transmission...
Thought I'd throw up some shifter stuff for the 901. Sorry about the small pics, I stold these from the Pelican website. But obviously don't spend money without adjusting first.
angela
The 915 was always a stronger transmission. So if you were going to build a high hp engine or very torquey engine, you went with a 915. First is unsupported in the 901, the 915 is much improved in this area. As far as the 901, 2nd thru 5th are are pretty darn strong.
The 915 is also significantly heavier and larger than the 901. George chose well. The dogleg shift pattern is uber-cool vintage racer style. The transmission is light and well suited to that car.
I've spent a fair amount of time between 901 and 915 transmissions. Honestly, they are both pretty darn vague in the shift pattern. There is no distinct gated feel as there is with other transmissions including muncies, saginaws, even alot of cable shifted FWD cars have more precise shift action.
I suspect the transmission in question may have a linkage adjustment issue. Beyond that, these transmissions greatly reward light handed drivers who practice. I've been teaching myself to play the guitar. I think the guitar is easier than than my initial learning curve on a 901 transmission...
Thought I'd throw up some shifter stuff for the 901. Sorry about the small pics, I stold these from the Pelican website. But obviously don't spend money without adjusting first.
angela
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If I remember correctly, and recall what Henry was telling me when he took me for a test ride in George's car before delivery, George had some "trick" short shifter device installed on the car.
Henry said it was very stiff and need a bit of adjustment and then some use to loosen it up. I doubt the car has had much use and the shifter probably needs some adjustment.
Henry said it was very stiff and need a bit of adjustment and then some use to loosen it up. I doubt the car has had much use and the shifter probably needs some adjustment.
It was the driver that needed adjustment. I think with a little use it will break in!
Dale - indeed - if George put in one of the "short-shifters" they are more challenging to drive than the standard ones. And from what I've heard, they are also more adjustment sensitive. So you may be right on with that one.
You know, I wish I could have met George. I've read some of his old posts when I'm in a "research" mood - smart guy. Opinionated, but very very smart.
angela
You know, I wish I could have met George. I've read some of his old posts when I'm in a "research" mood - smart guy. Opinionated, but very very smart.
angela
Renn Shifter sound like we should all buy this over the Weltmeister shifter. What do you guys thinks it's
$500 bucks
-----------------------------------------------------------------
Rennshifter
www.jwesteng.com
All brand new parts - no need to reuse your old housing or stick.
NEW EXCLUSIVE: User can easily switch between 20% or 33% throw reduction as desired.
Adjustable bias spring gates can be tailored to driver preference for precision shifting.
Over-travel stops give solid feel and protect linkage and transmission.
Versions to fit 911 with 901, 911, or 915 transmissions and 914 with tail-shift or side-shift transmissions.
The RennShift is a complete shifter and will give you more features than any combination of shifter upgrades on the market.
-----------------------------------------------------------------
George Brown words ------The 901 transaxle has a fairly long shifter throw; this can be alleviated by installing a Weltmeister shifter kit the
Weltmeister sells for about $100 and can be ordered through most Porsche dealerships.
Shifting with this kit is faster and smoother. Its also a good idea to replace any bushings
and springs in the shifter assembly that may be worn.
$500 bucks
-----------------------------------------------------------------
Rennshifter
www.jwesteng.com
All brand new parts - no need to reuse your old housing or stick.
NEW EXCLUSIVE: User can easily switch between 20% or 33% throw reduction as desired.
Adjustable bias spring gates can be tailored to driver preference for precision shifting.
Over-travel stops give solid feel and protect linkage and transmission.
Versions to fit 911 with 901, 911, or 915 transmissions and 914 with tail-shift or side-shift transmissions.
The RennShift is a complete shifter and will give you more features than any combination of shifter upgrades on the market.
-----------------------------------------------------------------
George Brown words ------The 901 transaxle has a fairly long shifter throw; this can be alleviated by installing a Weltmeister shifter kit the
Weltmeister sells for about $100 and can be ordered through most Porsche dealerships.
Shifting with this kit is faster and smoother. Its also a good idea to replace any bushings
and springs in the shifter assembly that may be worn.
I just read up on the Weltmeister Short Shift kit on this sight
http://hypertec.ws/todd_porsche/photos/shifter/shifter.html
Sounds like the renn is more advanced than the Weltmeister
http://hypertec.ws/todd_porsche/photos/shifter/shifter.html
Sounds like the renn is more advanced than the Weltmeister
Yo Angela, looking for some 911 info. Want to send you a PM. You and steve use the same email address?
D
D
Email address is unchanged. Not smart enough to learn a new one!
Laneco (at) internetcds.com (obviously no spaces)
angela
Laneco (at) internetcds.com (obviously no spaces)
angela
If you are going for a different shift, the Renn Shifter is much better over all....
I have one for my 914, makes a world of difference....
Michael
I have one for my 914, makes a world of difference....
Michael