Just recieved my 944..

..and man is it sweet!!

1987 NA, manual transmission, LS1 swap.

There is only one thing I'm not crazy about: At highway cruising speeds in 5th gear, the RPM's are high. At 70mph, I'm at 3000 RPM. Ideally it should be at around 2000. Is there anything I can do about this?

Thanks!

Get a turbo transaxle, swap in an early NA 0.78 5th gear, while you're at it install a reinforcement plate. Now you have the hot setup for these cars. Welcome to the board!

Be carefull, not all NA 5th gears are 0.78, I found out the hard way.

The taller NA 5th gear is 0.73. It will lower rpm around 400-500 or so, which will help, but you'll never see 2000 rpm...

Perhaps I meant 0.73 also.

Me too and I believe it has to be the early cars, pre 85.5.

The biggest 5th gear rpm drop you can get with USA gears is from the 80's Audi 5000 Diesel, the right box has a 0.68 5th gear that got me from 3000 rpm at 70 mph down to 2300-2400. Do a search on this site for "audi 5th gear," lotsa info. Apparently there were also 0.60 and 0.64 5th gears that were used in Europe.

Slightly dumb question. Would the tall audi gear kill a track car? I know 1-4 is a little on the short side for gearing but do people use the turbo 5th on a track or would is 5th not really touched on tracks?

You'll never use 5th gear on a track. 4th in the turbo trans is good to 140mph.

Agree... And I just happen to have one I can sell. $500.00 and it is yours!

What are you selling for $500?

The entire 1986 Porsche 951 transmission.

Is that the AOR with a cooling system
and the shot-pead front gears?

bp944 wrote:Is that the AOR with a cooling system
and the shot-pead front gears?

No it is cooled, but it is not the AOR. I f it were an AOR I would be asking for waaaaaaayyyyyyyy more money than $500.00!!

zeusrotty wrote:

bp944 wrote:Is that the AOR with a cooling system
and the shot-pead front gears?

No it is cooled, but it is not the AOR. I f it were an AOR I would be asking for waaaaaaayyyyyyyy more money than $500.00!!

And I actually have two of these.

docwyte wrote:You'll never use 5th gear on a track. 4th in the turbo trans is good to 140mph.

After 5 years with the 0.73 5th gear and stock rev limit here are my observations.

On the tracks that I run I have used 5th to achieve speeds above 140, with the needle pegged at Road Atlanta being the fastest. Even with the 0.73 gear, I have never reached the theoretical top end of the standard turbo 5th gear (0.83) which is 171 for my wheel/tire set up.

I have chased a few cars on long straights that I probably could have gained on or even caught if I had the original 5th gear because there is a slight loss of torque when first upshifting into 5th. Particularly the newer GT3s and some of the Corvettes.

I can assume based on the above that the 0.73 gear would be good for street use as it does lower the revs at cruising speed.

When the current tranny comes out I will be going back to the 0.83 5th.

My 2 c, ymmv

Marc

Good feedback, Marc. There is a middle ground. I picked up a .78 5th gear from an S2 transmission. It cost me $100 for a Porsche dealer to bring it in from Germany. I've not run it yet but plan to put it in before I install an AOR tranny this winter.

Rich