johntorg

A friend will be running an SP1 944, that I built and own, at Sebring, in the end of January.

The car currently has an LSD and Tall 5th Gear. I can swap in a short 5th non-LSD transaxle for the race.

I'm pretty sure the tall 5th will kill us on the back straight, but have no experience running an open diff 944 at Sebring. I would appreciate comments from anyone who has, or who has a theory.

There is some possibility that I can install a short 5th in the LSD trans, but I have a lot of work to do on my 944 S2, which sits engine-less in my shop waiting for parts.

Ernie J

LSD ,Really shouldnt be a issue , but you want the short 5th.Do it while waiting for parts for your car.

johntorg

Ernie, Thanks I will try to swap the 5th gear, but I will at least install a short 5th Non-lsd for the race. Super busy between now and Sebring. Just bought another SP2 race car which I may borrow the LSD short 5th transaxle from.

johntorg

BTW I blew the Short 5th LSD transaxle in my S2 race car (see avatar) and am running the S2 LSD with the in-between 5th. So I really have 2 5th gear swaps to perform.

Falcondrivr

I'm just a de guy, and in a 993. But my car does not have a LSD and it really needs it at Sebring.

amso3

John

I see you are in SC so I thought I'd compare Sebring speed to Roebling. I hit my rev limiter in 5th entering turn 1, and at Sebring I do not hit the rev limiter (but do get close) on the back straight. I do have a short 5th gear in a 911. So it really depends on what you mean by "short". LSD will help especially coming out of turn 7 at Sebring

johntorg

For the 944 there are only 3 gear ratios available: Long .7297 Short .8286 and intermediate (944S2) .778

Every one except the Short ratio kills your speed on the long straights. There is too big a gap between 4th and 5th.

Sterling Doc

I've seen the short 5th swapped with the trans still in the car by cutting a hole in the spare tire well, or cutting it out. This may be more simple than a trans swap.

I agree with short 5th > LSD. You can drive around open trans issues in a 944, but the tall 5th is a killer in tracks that use 5th gear.

Eifeler

Also agree. I spent several years in an open diff D Stock running around Sebring and the only turn that really screams for an LSD is the safety pin.

johntorg

Thanks for all your input. it looks as if we will have time to install the short 5th in the LSD transaxle that's in the car. See you at Sebring

944Cup

And the long and short are only legal options for SP2.

johntorg

Fortunately mine is an SP3 car, but going to a short 5th before Sebring. I had to re-install the stock S2 LSD transaxle after blowing up the short 5th box at VIR. The short 5th from a turbo transaxle fits. The SP1 car had a short 5th installed last week. These are busy times with the last race of 2012 in December and the first race in Sebring on Jan 30th. Not much of an off-season.