"many manufactures today gear cars specifically for thoses tests, but when they are raced in a more real life situation the story is different."

Yeah, like the Toyota Celica that's getting so popular with the ricers. It's geared so low, that it redlines in top-gear at 132mph! Even if you were to add power mods, you're still not going any faster than that!

"I was told the 951 clutch is "backwards", so a centerforce clutch at speed would have less clamping pressure due to centrifical force working against it?"

The way the weights are arranged, they increase the spring clamping force on the disc at higher RPMs, not sure how you can reverse that.

I think perhaps it's the release-bearing that you're thinking about? The ones on our cars spin all the time, rather than just when it's pressed against the pressure-plate.

Also my Centerforce has lasted twice as long as the 'Cup' clutch kit that was installed in my car previously, and its only 1/2 worn. So I'm guessing it will last 4x as long as the 'Cup' clutch kit. Not to mention it doesn't slip under high power applications.

 

Where's the best place to get a centerforce (price wise)?

 

My best times.
4.8 0-60
13.2 1/4 @ 112mph (inflated G-tech speed)
This on a stock k26 turbo @ approx 18psi

Don't know if I will ever try to beat/match this, (or even try). It does feel a LOT faster then my stock car.

DanD 86 951 *2
K&N cone intake, HR MAF Stage I (upgraded to III), custom intercooler hard pipes, ARC II fuel controller, ARM1 air/fuel meter, AutoThority Stage II chips, APEXi AVC-R electronic boost controller, shimmed wastegate, free flowing PowerEffect adjustable muffler. Autopower rollbar, 400# front Koni adjustable shocks, 300# rear(Hal/QA1) + 25.5mm torsion bars, , aggressive track alignment.
2nd car, Stock so far...
<a href="Http://members.rennlist.org/dan10101" target="_blank">Http://members.rennlist.org/dan10101</a>

 

Since the "S" is heavier than the older 944T's, to get through the 1/4 in the 12's will require more power. Assumming that you have tires of at least 225 mm width and a fairly soft compound, I suspect you would need close to 380-400 H/P to run consistently in the 12's. Other assumptions include weight of 3200 lb, stock gearing, locked differential, adequate shifting, close to sea level, ambient below 100f, decent traction at the strip. Now... the question is, what do you need to do to make 400 H/P? I am a firm believer that the Porsche transmissions in the 951 or 968 deliver 90-92% of the available power to the ground. That is one of the reasons you'll see a Porsche car turn 1/4 times that are as quick as cars with similar power/weight properties, gearing, etc. Some people would have you believe that Porsche understates their H/P. That's not the case. Their H/P figures are accurate. Their tranny's are very efficient. So, if you measure the H/P at the rear, 360 H/P on an accurate (more than a few that aren't) rear wheel dyno should do the trick. Clarification on the dyno accuracy..It has a lot to do with the operator, as well.

 

"Where's the best place to get a centerforce (price wise)?"

I think <a href="http://www.performanceintl.com/shop/year.cgi?comp=cf_imp&make=PORSCHE&model=944" target="_blank">Performance International</a> has the best deal on a Centerforce clutch kit. But I think that's only for the pressure-plate and disc. You'll need the throw-out & pilot bearings. A clutch-fork, needle bearings and crank-seal as well. I think Bill mentioned that Windward (800) 642-1348 had the best complete package price.

 

There is that company again Windward. Bad things.

I think there are some threads on the subject of Windward.

2+2 If you have a copy of that article about the Z and the 951 I would love to read it.

On another note I don't know what it is about 951's but they just seem to attract kids in Mustangs and Ricers triying who want to race.

I just don't understand it. <img src="graemlins/burnout.gif" border="0" alt="[burnout]" />

 

I will heed all of your warnings re. clutch and CV and choose my battles carefully. No honduhs from a stop.

Hey DanD, from the looks of your info, 0-60 sub 5 and 1/4 in sub 13 most likely requires a turbo upgrade, MAF, chips and exhaust. Cool. thanks.

Here is the link comparing 90 300ZX TT with 89 944 Turbo. Enjoy.

<a href="http://www.angelfire.com/ga/300zx/images/indexauto1189.html" target="_blank">http://www.angelfire.com/ga/300zx/images/indexauto1189.html</a>

 

BTW, the Z TT's can be made into 400 hp (crank) by getting a chip, cone intake and free flow exhaust for about $2000. That usually gets them into low 5s or high 4s 0-60 and 1/4 in low 13.

 

"On another note I don't know what it is about 951's but they just seem to attract kids in Mustangs and Ricers triying who want to race. "

Really? They pretty much leave me alone... Maybe I should put some stickers on my car to tempt them... Like a 'Porche' windshield banner and perhaps a 'Powered by Sauerkraut' on the rear quarters, yeah, yeah, that'll get them!

 

2+2, where did you find those articles?

I have been searching for old articles comparing and testing the 951. Know of any comparing 951 and corvetts? <img src="graemlins/beerchug.gif" border="0" alt="[cheers]" />

 

I have one comparing a 86 951 to a 86 vette to a 86 rx7 turboo (II i think). It's paper though and my scanner isn't workin right now.

 

I've got a copy of that article somewhere. I'll see if I can't dig it up and scan it...

 

The Z comparo article was posted way back by someone who owns a Z in a Z forum. I still own a 92 2+2 Z. I hate to sell it but I have to for my Turbo S.

 

[quote]I think Bill mentioned that Windward (800) 642-1348 had the best complete package price. <hr></blockquote>

Danno is correct. Windward supplied all the required parts, for the best price. I did not use the aftermarket rear main seal. It has been my experience that the Porsche seals are superior. (and who wants to redo a clutch job due to an oil leak). I like Danno, love the Centerforce clutch.

[quote] There is that company again Windward. Bad things. <hr></blockquote>

The Centerforce clutch has been the only item that I purchased from Windward, but I had no trouble. They even went the extra mile for me. When I ordered, they did not have the clutch in stock. I did want the clutch as soon as possible, so Windward had Centerforce ship directly to me. Windward then sent the remaining required parts separately. They did not charge me any more shipping than if I would have gotten the one direct shipment.

I will not hold back when someone does me wrong, but I also give cudos when earned.

 

Danno

Did you have any luck on the article with the turbo II and the vette? I would really like to read it. <img src="graemlins/xyxwave.gif" border="0" alt="[bigbye]" />