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First DE with the LS1 coming up this weekend!

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Old 10-05-2010 | 09:58 AM
  #46  
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Glad to hear that the car made it to Mid-OH but sorry to hear about the carnage. I like the plan of going with a Spec clutch for the track. Interesting to hear about the brakes as I am thinking of putting manual brakes in a car, they work great on a kart. Maybe the Wilwood master cylinder is the answer or the dual MC like you are thinking.

Driving home with clutchless shifting is fun isn't it? I got to do that once in the old 968 from Putnam, what an experience.
Old 10-05-2010 | 10:02 AM
  #47  
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I've driven an LT1 944 (former NA version) with manual brakes on the street and it wasn't the best braking option for that setup even though I got used to it.

I can only imagine what it must have felt like on the track at those speeds...sorry to hear about the clutch carnage.
Old 10-05-2010 | 10:44 AM
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I'm running a hydroboost setup on my LS1 car, so is TonyG. Mine is from a Ford Mustang I think.

Why did you use the Dodge disk vs something designed for the LS? I went with a Spec stage 2...
Old 10-05-2010 | 10:54 AM
  #49  
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+1 on Spec Clutch. Good guys to work with and they have these designed specifically for the swap application.
Old 10-05-2010 | 07:39 PM
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Originally Posted by docwyte
I'm running a hydroboost setup on my LS1 car, so is TonyG. Mine is from a Ford Mustang I think.

Why did you use the Dodge disk vs something designed for the LS? I went with a Spec stage 2...

Well, I considered the spec clutch and pp, but I had a z06 pressure plate already, and the dodge disk was really inexpensive and easy to get at local parts stores. Based on a few posts from others who have done the swap, I was under the impression that it could handle my hp level just fine (and I think it worked ok until I took it to the track). It seemed like one of those no-brainer decisions at the time. I can now clearly see that it was a mistake. Spec clutch is going in next.
Old 10-05-2010 | 08:24 PM
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How did your manual steering rack feel at the track? What wheel and tire combo did you run?
Old 10-05-2010 | 09:37 PM
  #52  
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Originally Posted by vt951
Well, I considered the spec clutch and pp, but I had a z06 pressure plate already, and the dodge disk was really inexpensive and easy to get at local parts stores. Based on a few posts from others who have done the swap, I was under the impression that it could handle my hp level just fine (and I think it worked ok until I took it to the track). It seemed like one of those no-brainer decisions at the time. I can now clearly see that it was a mistake. Spec clutch is going in next.

I have beat the crap out of a NAPA dodge disk and its still all together, I am sure depending on chain store location there are many different suppliers for the "same" disk. Luck of the draw I am sure. Then again i had a custom kevlar cluth disk BTFU over poor workmanship / bad bonding agents.
Old 10-05-2010 | 10:36 PM
  #53  
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i think that his factory master cylinder may not be pushing the pressure plate out far enough and it was slightly dragging on the disc even though it was releasing. This may have over heated the organic disc and caused it to come apart after some abuse. I think a better disc and bigger master cylinder, coupled w/ some real brakes and this car would be a monster. He needs to get it perfected so i can do mine should i ever blow it up.
Old 10-05-2010 | 11:10 PM
  #54  
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I went with a Wilwood 7/8" clutch MC, not a missed shift yet and excellent clutch feathering control.
Old 10-05-2010 | 11:17 PM
  #55  
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How firm is the 7/8" MC? I have been debating between that and a 13/16".
Old 10-06-2010 | 08:31 AM
  #56  
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The clutch pedal with the 7/8" MC is a little bit firmer than a brand new 944 MC on a brand new 944 clutch let's say. Let's not forget that the LS PP's and concentric throws have more volume and longer Tine throw than the factory 944. It has been discussed before that the 944 MC on the LS clutch may not be disengaging the PP from the disc and causing premature wear and gear grinding in some cases. I would say try the 13/16" if you have an F-body or Vette PP, but the Spec clutch's PP tine throw is an unknown....to me at least.....I've heard of some folks having to remove the Spec clutch (we all know what that entails) and re-shim between TO bearing and PP, others not .....I would rather not.
Old 10-06-2010 | 08:34 AM
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Originally Posted by arthropraxis
How did your manual steering rack feel at the track? What wheel and tire combo did you run?
Manual steering felt excellent on the track. It was actually the first time it ever felt excellent, and I think it's because I popped the camber plates in and probably had about 2 or 2.5 degrees of negative camber. On the street, with almost zero camber, it feels pretty heavy in slow corners. I'll probably start running a little camber on the street in the future to help with that.

I was running:

front: 245 - 17 Hankook RS2
rear: 255-17 Falken RT615

No good reason for the odd tire combo, just that my Falken fronts were bald and I had the Hankook sitting around.
Old 10-06-2010 | 10:49 AM
  #58  
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Spec stage 2 Kevlar with a 7/8 master will be good I have used that combo for quite some time. XSboost is correct the disc was probably dragging and it might not have been of the highest quality. I ran the same Spec disc for 7 years in my 968 and it performed flawlessly with only 20% disc wear over that time. With the 2pc C5 bell housing you can check the travel of the pressure plate, TO bearing and see how much it releases the disc before you put it all back together. The bearing needs to have at least .030 clearance from being bottomed out to allow it to move rearward as the disc wears over time. With a Spec clutch and the 7/8 master I haven't ever used the shim. As for the brakes I have tracked with manual brakes for many years but it wasn't until I went to dual masters with a balance bar and Stop tech 14" front rotors they they really worked well from speeds over 120mph. That being said on my new car I am utilizing the ABS electric power master. I am sure once Allen gets another clutch in the car and some assisted brakes the car will be reliable and fast.
Old 10-06-2010 | 12:11 PM
  #59  
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Originally Posted by xschop
I've heard of some folks having to remove the Spec clutch (we all know what that entails) and re-shim between TO bearing and PP, others not ......
FYI - when I bought my clutch from spec they suggested shimming if running the 944 matser and included the shim just in case I used the stock mc.

Davis Norton at Spec is a good guy to work with. He has a 944 conversion of his own so understands the issues we face.
Old 10-06-2010 | 12:33 PM
  #60  
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The only question I haven't seen answered is the tine throw relation between a Spec PP and a factory F-body Vette PP. I am definitely not questioning the quality material that a Spec clutch disc may or may not have. I only wanted to know what part# Dodge clutch disc that VT951 was running.

I do know that a factory Vette clutch disc that I had in hand was built using 36 rivets and 5 damper springs. The CP-4018 has 40 rivets and 6 spings the same size as the Vette springs and also has more plate fingers out to the clutch material than the Vette disc.....FYI


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