TheSamba.com :: View topic - 901 trans identification for 911 4 or 5 speed?

Mon May 28, 2007 8:18 am

Can any one tell me how to identify a 901 trans for a porsche 911.

Also, how do you tell if it is a four or 5 speed?

Can it be shifted while out and on the floor to tell?

Any help would be appreciated.

Chris

Tue May 29, 2007 3:09 pm

i have a pictures of both but I'm new to loading img shoot me your email add and I'll shoot them to you :wink:

Tue May 29, 2007 3:39 pm

emailing them to me & I will post your pics in this thread

[email protected].

-Mark

Wed May 30, 2007 5:58 pm

pic's from David Manzano. Apparently the 4 speed has a smaller case & 5 larger

4 speed:

5 speed:

notice the perpendicular lines over the case

Thu May 31, 2007 11:49 am

That second pic doesnt look like a 901

902/01= 5 spd
902/0 = 4 spd alum case
902/02=5spd mag case
902/50 =special trans for hillcliming
These are for a 912(4 cyl)
PS. 902/0 was used on a 6cyl but i dont think it was sold in the US.

901/02 = 5spd 6 cyl
901/50,51,52,53,54 are all special order trans for a 6cyl
901/10 and 901/11 are 4spd trans for a 6cyl

They are all stamped on the bottom, by the seam

Thu May 31, 2007 12:50 pm

well the number is 901.901.001 or something like that, i'm not looking at the trans at the time :shock:

Thu May 31, 2007 1:26 pm

I'm not saying that its not.

The cone is the same but I have never seen the ribs like that. I think that, that is a mag housing and the other is a alum(mag 69 to 71, alum 66 to 68)

Sat Jun 02, 2007 1:24 pm

Is it really any diffrence in the transmissions between 911 and 912. Didnt they use same stuff on both models (early 65-69) ?

Sat Jun 02, 2007 4:51 pm

Its the same case/trans from 66 to 68 (alum) and the same from 69 to 71 (mag). 912's ended production in 69. Starting in 72, 911's went to a 915 trans.

In the first pic it's alum, in the second, it's mag. They are the same just a different case.

911 and 912 trans are the same trans just different gears.

Sun Jun 03, 2007 2:00 am

bt wrote: Its the same case/trans from 66 to 68 (alum) and the same from 69 to 71 (mag). 912's ended production in 69. Starting in 72, 911's went to a 915 trans.

In the first pic it's alum, in the second, it's mag. They are the same just a different case.

911 and 912 trans are the same trans just different gears.

Okey thanks, great answer! I guess that the 912 tranny will RPM more? I have a flat6 1969 911 engine, will that be a good combination to a 4 or 5 speed 912 transmission? Will it fit togheter, flywheel, clutch etc?

Sun Jun 03, 2007 8:51 am

I dont think it would be geared correctly (to use a 912 trans on a 911).

It will fit together and the clutch cable works the same.

Talk to these guys, they build 912 trans. They can give a more tech answer.

carquip (303)443-3715
7191 Arapahoe Rd.
Boulder CO. 80303

Dave Folts trans
631 E Lambert RD unit C
LaHabra CA 90631
(562) 694-5591

I see that you are not in the States, I dont know if either has a webpage.

Tue Jun 05, 2007 11:58 am

bt,
here's the pic of the number, but I'm confused because i dont see the 301 series in your list would that mean that it's a 4 speed ? :shock: but any help would be great ....

Tue Jun 05, 2007 3:42 pm

I'm not sure what number that is. I put it thru Pelican parts locator and it didnt come back with a part.
That is of course a 911 part(I'm not sure what year they started using 911 in there codes but it was not until the late 60's early 70's. Remember the car was orginally called the 901 before Renault said they would sue. Thats why all there early part numbers start with 901.

The trans number should be on the bottom and it will start with 901 or 915 (on the long hood models).

All early 911 trans in the US are 5spds(excluding turbos but they didnt begin until 76)

Take another pic and get a pic of the complete trans.

Over the years I have seen people convert 912's into 911's without changing the trans to a 911. So it can be done. I dont have any info on where their RPM's are, when they are on the highway.

Thu Jun 07, 2007 9:28 am

Something that was not asked but should be added.

The drive flanges are different on 901 trans. 69 to 71 has a larger flange than a 66 to 68. You can see the difference in the pics.

I believe that the flanges are the same for a 69 912 and 911 as well as a 66 to 68 912 and 911. Its been a long time since I checked them so FYI if you are doing a conversion.

Mon Jun 18, 2007 4:32 am

Quote: 902/01= 5 spd
902/0 = 4 spd alum case
902/02=5spd mag case
902/50 =special trans for hillcliming
These are for a 912(4 cyl)
PS. 902/0 was used on a 6cyl but i dont think it was sold in the US.

901/02 = 5spd 6 cyl
901/50,51,52,53,54 are all special order trans for a 6cyl
901/10 and 901/11 are 4spd trans for a 6cyl

Flip it over, the actual type numbers are stamped on the bottom of the trans ,below the ring gear, on the center rib.

Mon Jun 18, 2007 11:50 am

901/13 ser.#7196265 what kind of tranny is that? 5 speed 911??

Fri Jun 29, 2007 1:39 am

Quote: 901/13 ser.#7196265 what kind of tranny is that? 5 speed 911??

5 spd 69 911 afmsz

Fri Jun 29, 2007 4:01 pm

wheeldude wrote: Quote: 901/13 ser.#7196265 what kind of tranny is that? 5 speed 911??

5 spd 69 911 afmsz

Like I thought. Thanks man! :wink:

Wed Jul 11, 2007 9:11 am

That trans is a 1969 only mag case. The magnesium has deeper ribs and a dull finish. It corrodes very easily, too. The next year, 911's went to a pull type clutch, so the 1969 is a one year only thing. Incidentally, this trans is very similar to a 914 tranny. I think they were AFMSZ, too. Of course the ring gear was flipped and the 914 had a different nose housing. Tail on a 914, I guess.
911's and 901's generally used the same gear ratios and r&p ratio. Apparently, the 911 made power at higher rpms and the gear spacing worked fine with either engine. These Porsche gearboxes could change any gear set separate of the others. Each available gear set had a letter designation. A, F, M, S, X was the group of standard gears for 65-68.
An airport (short course racing, not banked) set was A, E, I, O, U. Since 2nd gear on the standard set was integral with the main shaft, if one wanted to change 2nd gear ratio he needed to get a 904 mainshaft and the appropriate 2nd gear set, like "e"
All this stuff was rather expensive. A complete custom ratio box could cost about as much as an engine.
The very early cars used Nadella u-joints which were not C_V's but rather X-type joints with an extra swing link on the inner flange. I once had a very early 1965 912, but it had the Loebro joints. I'm not sure of the application of the Nadellas.
Al