Tyoe 902/01 912 5 speed box

[gilbert911]

Is this going to cope with 190/200bhp of 911 power?

[Jeff Trask]

I think there is no difference other then the serial number. Ratios are the same as an early 911. No internal differences.

[Alan.uk]

Hi,

A 912 box has different ratios. Is it a 5 speed? 902/01 I did think was 4 speed, not 100% sure though.

Anyway a pic always helps

Alan

[preS]

Isn't his question whether the box can handle the 911 (190hp) power?

Richard

[Jeff Trask]

The answer to his question is, Yes!

[Grady Clay]

The 902/02 is a ’68 5-speed geared AFMSX . It has the infamous simplified differential that needs the upgrade (search Pelican on ‘Simplified Differential’). It should have the 14 mm thread reinforced input shaft.

What year car? What displacement (torque) 911 engine?

With good parts, new bearings (and possibly an oil pump, filter & cooler), I think a 901 can handle 2.8 liters and 250 hp. You cannot do jackrabbit starts or let it get too hot. A torquey 3.0 or 3.2 is too much IMHO, others disagree.

Best,
Grady

[gilbert911]

Thanks,
What is the practical difference between a 902/02 and a 902/1??
Seem to be the same ratio's etc..

[Grady Clay]

The earlier 902/1 has the regular non-simplified differential and the 902/02 has the simplified differential. The 902/1 has the non-reinforced (12 mm thread) input shaft and the 902/02 has the reinforced (14 mm thread) input shaft. Yes, the ratios are the same. There are a few subtle hardware differences.

The serial numbers for the 902/1 fall into three groups:
220001-221721 to July 26, 1965
234001-238942, ’66-’67 912s
130001-131571, ’66-’67 911s
While these are official Porsche numbers, I’m not sure they are complete or correct.

The serial numbers for the 902/02 are listed as:
x280001-x289999 where x could be 1,2,3 or 4 depending on it being installed in a 912, 911T, 911/911L or 911S.. The ’68 numbering system is very poor, ’69 was vastly improved and the ’70 through ’80 was nicely consistent. There are some identical engine numbers in both ’70 and ’80.

Best,
Grady

[302672]

gilbert911,

Pay head to Grady's post. 902/1 Transaxles having the non-reinforced (12 mm thread) input shaft surely will require a rebuild either before it breaks or after with 190/200bhp engine. Speaking from experience, my basically stock 901/01 with 'S heat exchangers and Bursch exhaust snapped on a rather unagressive stop light launch. There was good news, did not need a tow. Car continued to run great in 2,3,4 and 5th. However, with no reverse it presented a problem, sometimes. As most early 911 drivers know first is only briefly used and you can get along rather nicely without it. A rebuild is not terribly expensive relatively speaking - suggest do it before rather than after. By the way, the main shaft with 14mm thread probably should be ok (I trust). Just my $0.025 worth.

Have Fun!
JohnB

p.s. Could not locate a 904 shaft at the time, so we settled on the 14mm shaft. Dealer was generous, providing parts (bearings, sync's, & 1st gear set)at basiclly his cost.

[gilbert911]

Grady & JohnB,
Thanks for the help.
The engine is 2.4 enlarged to 2.5
Power will be as I say (@200bhp)
The 902/1 box will be rebuilt before it goes in
Date on case is 12/66
Specifically, what needs to be done/go in so it doesn't snap?

Thanks so much