901 transmission variations

[derekfiveo]

I have started my roller project 912 and am starting to look for a transmission. Questions regarding 901 transmission.

Porsche 914 901. I seem to find more of these. What is required to swap the gearing for a rear engine car? Is this a thing that’s just not worth the trouble?

914 had tail shift and side shift. If I was able to fix the gearing. Which 901 should I look for?


Standard 901.

I see a lot of transaxle cases. Is there any cost effectiveness to buy a case and all the gears separate to put one together ? I feel like parts would be far to inflated to buy separate.


I have a 1968 912. Other than the 901. Is there any other transmissions that fit? 915?

[djpateman]

The 901, 902 911, and 914 transmissions are very similar, and many components can be interchanged. The 915 is quite different, and would probably not fit without clearance issues. So the 901 series was initially for the 911 and the 902 for the 912 with slightly different gears. In 1966 both 911 & 912 used a 902 transmission. 1967 was a bit more complicated, but 1968 there were about 17 transmission variations. Almost every one had an aluminum case. In 1969 they transitioned to a magnesium case. For 1970 the 911 had the 911 transmission which was little different from the 1969 version, but the flywheel, clutch, and clutch actuation were completely different, and so not as easy to convert for you. The 914 was similar to the 1969 transmission, but the mount was completely different as was the gearshift connection, the vent location and of course, the differential was flipped in the case to rotate in reverse. In short, a 1965 through 1968 transmission should fit without issues except for the output flanges. They need to match the axles you have or at least the stub axles in the axle bearings. If I knew your VIN then I could guess which transmission you should look for. Buying a transmission piece by piece would be very expensive. PM or email for advice.

[stownsen914]

901s had a few variations. Many parts are interchangeable across the models, but not all. The early ones were aluminum and had a different differential than the later ones. The magnesium case started around 1968 (?). The 70-71 version (technically a 911 instead of 901) had a different clutch release mechanism, so the case and clutch fork are different. The 914 trans (there are actually two versions) is similar to the 911 mag case trans with the earlier style clutch, but has different shift forks and a different nose cone. Generally a lot cheaper to buy a complete trans, even if core, than to accumulate parts and build one.

Swapping to a 915 is a bigger deal, and 915s have gotten expensive.

[derekfiveo]

Originally Posted by djpateman

The 901, 902 911, and 914 transmissions are very similar, and many components can be interchanged. The 915 is quite different, and would probably not fit without clearance issues. So the 901 series was initially for the 911 and the 902 for the 912 with slightly different gears. In 1966 both 911 & 912 used a 902 transmission. 1967 was a bit more complicated, but 1968 there were about 17 transmission variations. Almost every one had an aluminum case. In 1969 they transitioned to a magnesium case. For 1970 the 911 had the 911 transmission which was little different from the 1969 version, but the flywheel, clutch, and clutch actuation were completely different, and so not as easy to convert for you. The 914 was similar to the 1969 transmission, but the mount was completely different as was the gearshift connection, the vent location and of course, the differential was flipped in the case to rotate in reverse. In short, a 1965 through 1968 transmission should fit without issues except for the output flanges. They need to match the axles you have or at least the stub axles in the axle bearings. If I knew your VIN then I could guess which transmission you should look for. Buying a transmission piece by piece would be very expensive. PM or email for advice.

Vin 12803013


Thanks for info so far

[Joe Bob]

Back in the day, 914/901 transmissions were cheap. I actually gave away 4 trannies to 914 people on the now defunct 914club website. 20 years ago...

914world.com has a guy named Dr. Evil that does 914 boxes and is up to his rubber gloves in 901 parts. I would contact him and see where you can go from there.

Yes, he's a real doctor....MD not a jagoff PhD.

[sparkysvega]

There’s one for sale in the classifieds on here right now .

[oldie44]

I recommend you also decide what engine you plan to install along with your transmission. I think a 912 engine will be hard to find and very expensive if you find one.

[derekfiveo]

Originally Posted by oldie44

I recommend you also decide what engine you plan to install along with your transmission. I think a 912 engine will be hard to find and very expensive if you find one.

I have other plans that will make purists go ballistic as they pay for someone to change their own oil lol

[djpateman]

902/01 with serial 1080001 4 speed
902/02 with serial 1280001 5 speed
Both have the same first gear and top gear, so just the splits are different.

[Matt Monson]

Originally Posted by derekfiveo

I have other plans that will make purists go ballistic as they pay for someone to change their own oil lol

I think maybe you've confused this board with some place else. Pelican is a DIY forum. It always has been.

[jazzmens1]

914 to 911 is not a real big deal. Swap over ring and pinion and carrier bearing spacers, move vent, get 911 nose and shift rod. Don't know which CVs the 912 uses so may need new stub axles and I assume the speedo hookup is same as 911??