jchaley

I am thinking about changing out the tranny in my 944 turbo for a S2 tranny to get a lower gear ratio. I live in Denver at 5000+ feet and the off boost power and lag are one of the things I would like to change about my car. This car is a street car only and I have no plans to take it on the track. I use the car all year round as my daily driver. The car is currently stock except for chips and a boost enhancer. Anyone have experience using the S2 Tranny? Are parts interchangable between the turbo trany and the S2 (gear sets, differential etc)

thanks

john

special tool

Yes, they last. I have one that I switch in and out. Before I had it was a sPeedshop loaner that was getting short track use for years by cup cars and 400 hp. track cars. It is still unopened and tight as a drum. And it does give better accel.

Flight_951

[quote]Originally posted by jchaley:
<strong>I am thinking about changing out the tranny in my 944 turbo for a S2 tranny to get a lower gear ratio. I live in Denver at 5000+ feet and the off boost power and lag are one of the things I would like to change about my car.</strong><hr></blockquote>

You didn't mention which chips you have but maybe a set of Guru Racing chips will help. Much cheaper and lots less work to install. I noticed a big increase in throttle response over the autothority stage II that I had removed. HTH

GrantG

JCHALEY - OT, but I drive my 951S all year in Denver too, and in case you don't have them yet, used 928 wheels flat with the sausage shaped openings areound the perimeter (forged in the 16x7 size all around) with 205/55 Dunlop M2 tires works wonderfully in the snow. Especially, if you have ltd slip diff.

GrantG

Question: Is the S2 tranny a 6spd like the 968? If not, why not get the 968 tranny (is it harder to make it fit - I know racers love the 6spd box)?

CMF

I have S2 tranny with the LSD, its very good.
7200rpm=268KM/h (245/45/16") Acceleration in 5.gear is amazing.

<img src="graemlins/beerchug.gif" border="0" alt="[cheers]" />

GaryK

[quote]I am thinking about changing out the tranny in my 944 turbo for a S2 tranny to get a lower gear ratio. I live in Denver at 5000+ feet and the off boost power and lag are one of the things I would like to change about my car <hr></blockquote>

I'm here in the Denver area too, and yes the altitude is detrimental to spool-up. Take a turbo car to say Kansas and what a difference in throttle response! (Plus, you'll get more boost for a given setting on a MBC)

I'm with you and would like to swap out my tranny for a S2 one with the shorter final drive ratio. Here is a link to the some gear charts:

<a href="http://www.geocities.com/MotorCity/4475/Porsche/gearboxswap.html" target="_blank">944S2 Gearbox Swap</a>

Anyone know exactly what the improvements were to the Turbo S gearbox (hardened gears,etc)? Does the S2 gearbox have these updates and LSD as well?

Rich Sandor

also curious, is the LSD a PART of this S2 gearbox?

I have an 86 951. no lsd.

Since WOT in 5th would land me in jail anyways, why now switch it with an S2 box with LSD.

Where could I get such a thing? And how hard would it be to do the job?

marksportcts

The only 944 cars that had the LSD come standard in the tranny is the '88 Turbo S and all the Turbo's from '89 and on. The 944S2 and 968 have LSD as an option. I have an '89 turbo tranny on my '86 non-turbo. These LSD units are rebuildable as they are a clutch type.

Rich, where abouts are you in Van? I've met most of the other GV 944 rennlisters on the whistler run.

DanaT

Wow,

Lots of 951s from denver.

Yes...altitude kills power.

You will spend alot to get the 951 off the line in denver.

I couldnt get better than about a 2.2 60ft at bandimere.

-Dana

Rich Sandor

hey mark. I picked up my 951 the weekend after the last whistler run. Althought I just drove up to whistler just last night for pizza.

I live in Kits right now.

jchaley

ok, so it sounds like the S2 tranny is strong enough to live under turbo power. how about parts interchange. I have the cooler and limited slip on my turbo tranny, can I swap the limited slip into the S2 tranny? I might also be interseted in swaping 5th gear. If i decide to sell my turbo tranny how much do the cooler and limited slip units go for, I know they are not that common.

thanks

john

Olli Snellman

[quote]Question: Is the S2 tranny a 6spd like the 968? If not, why not get the 968 tranny (is it harder to make it fit - I know racers love the 6spd box)?<hr></blockquote>

No, S2 tranny is not a 6-speed.The biggest problem with 968 tranny is how to get your speedo work.968 uses ABS aystem for speedo.944 models have a sender unit in the tranny.

DanaT

After going through this “exercise” myself I came to a few conclusions:

1) New ring and pinion from PowerhausII was $2K. Way too much money for so little.
2) I am not sure if an S2 transmission will hold up. It is a costly experiment to find out.
3) I contemplated using a normal 944 tranny and just running it until it breaks and then put the turbo tranny back in. Again, costly.
4) Use nitrous to get on boost quicker in 1st gear.

What I realized, is that all of these options are expensive or can be dangerous for the engine. After going through the exercise over and over in my head, there is one thing to keep in mind. The 944 Turbo isn’t a good drag race car.

I also live at high altitude. There isn’t much I cant keep up with (within reason) once on boost. Off boost its another story. To get a good launch, I tried 3000rpm and 4000 rpm. Both of these launches the car bogged. Then I went to 5000 rpm. The car spun really, really well. I just kept into it and didn’t stop spinning until the top of 2nd. I was putting down times (and higher mph) than the vipers and almost all C5s (except the highly modified ones) were. My 60 ft times SUCKED. The car at high altitude makes the power (as evidenced by mph) to run about a 13.0 ET even at high altitude. I was running low 14s though (due to poor traction and/or poor gearing).

These are quick cars on the top end. They aren’t drag race cars though. I always am dreaming of having a truly fast 944 Turbo. Then I realize, it will cost me $100K to make it as fast as I want it to be. Reality sets in once again. So my solution: drive the 951 for what it is and realize what it isn’t. And if I really want to go fast (yes, the 951, even with all its mods, is damn slow) I just hop on the Hayabusa.

Now…how do I make the 951 as fast as the Hayabusa???????

-Dana

GrantG

Dana - If you really want to accept your 951 for what it is (and for what it was made to do), you should come out to the road course at 2nd Creek (near DIA). Tons of fun and free (for PCA members) Dec. 26th - Dec. 31st.

I promise you'll have fun (but you may still wish you had lower gearing - I do)

-Grant
88 951S