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Discussion Starter #1
After installing the p-trim clutch it had minor chatter when launching from a stop. As it started to break in (250-300 miles) the chatter increased, a couple of times (along with experimenting) the chatter rivaled wheel hop (added power to try and push through it).

At that point I was needing 2K+ rpm to get the car to launch smoothly from a stop consistently. At times I could launch normally with little or no chatter, then a stop or two later it would be back again.

Somewhere past 500 miles I was getting a little pissed at it. I never quite knew what to expect from it from one stop to the next. So I went to a parking lot and launched and stopped the car over and over trying different techniques. The only one that worked everytime was 2K+ starts with quite a bit of slipping, which seemed like too much IMO. After doing that a few times I went down to 1500 and then 1200 starting RPMs and it did fine with just a tiny bit of shudder as the clutch locked up. The engagement point also moved up in the peddle travel, then as it the chatter returned the engagement point went back to the stock location (like it had always been). I drove it more after that and then came back to the same parking lot and practiced launches again with the same results.

Today I rolled past 700 and then 800 miles and it's starting to get better, less chatter, minor at best today and plenty of launches that felt close to stock. It has been warmer (60's) and humid today instead of 40's.

For the first time the car barked going into 4th.

I'm not sure if it will ever let me slowly let the clutch out at idle and smoothly engage with out using the accelerator like the stock clutch.

So, tonight, I'm happier with it than I have been since day 1. No complaints when shifting gears, its always engaged smooth.
 

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Good write-up. I've got the SS-trim (rated to 900 tq) and it's been a lot better experience. Any reason why you went with the 1395 tq version?

HemiSam
 

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Discussion Starter #7
Given as often that I go to the track and the fact that the stock clutch was getting so hot it stank I had doubts that an organic based clutch would hold up any better. There was/is quite a bit of slip at launch to avoid bogging the engine too much, and that's were a lot of the heat came from. So I decided to go a step up and try the p-trim.
 

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Gotcha. For what it's worth...I took mine to the strip 3-4 weeks ago and ran at least 11 times within about 3.5 hours in ~80 degree weather. Smokey burnouts before each one to heat up the 555R drag radials. Zero issue with the SPEC and no burning smell. I'd have to slip it a bit at 2K rpm to avoid spinning the tires too much at launch. Granted, this isn't 200 times down the strip over a year, but I'm pretty hard on mine given I like different kinds of tracking and the blower puts down some power at the boost level I'm running. A buddy of mine shot this and will give folks an idea of how I ran it that day.

Also, no chatter like the RAM clutches. There was a bit when I first got it, but after a few hard burnouts, it was gone.

I hope your P-trim improves and gets you where you wanted to go, buddy. No fun going through the expense and trouble and then not getting the result you'd hoped for.

HemiSam

 

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That was in Sealy, K. The first car to run, a Mustang, dumped oil all the way down the track and clean up took over an hour and half... Once they cleaned it up, we did get to run and it's not a heavily populated track. That's good and bad since track prep doesn't look to be A-1 and it got pretty slick as the day progressed.

HemiSam
 

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Discussion Starter #11 (Edited)
The clutch seems to be doing good today, it's engaging pretty smoothly now.

Hemisam, you're easier on your launch than I am, but you have a blower to help with low end torque. To launch worth anything with drag radials takes around 4500 rpm.

Here's one that was little too high (skip to 0:36) and then hit the rev limiter:

 

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Nice runs!

Understood. I tried launching at 3000 (that was a joke) and 2500, but it only got me 12's. I can't get into it until well into 2nd or I'll just go sideways. I'm not complaining... Hopefully the 17" M&H's will help.

HemiSam
 

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Discussion Starter #14
1000 mile update.

The clutch seems to be settled in now. It is about as smooth as the stock clutch, and about the same as the 800 mile update. It does take a little more care at launch though, if it's engaged too quick it will yank the RPM down. Oddly the smoothest launches, to me the driver, have usually been starting around 1500 rpm and letting the clutch pull the engine down as the car accelerates.
 

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Discussion Starter #17
Are you still getting chatter on it?
Fairly rare now, but if I fubar the launch sometimes it will. Then again, I could get some minor chatter with the stock if I fubarred the launch too, but the p-trim chatter is a little more rough compared to that.
 

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Discussion Starter #18
5K mile update

One more update.

The clutch is doing better with city driving, I don't have to be quite so aggressive launching it for it to be smooth. The chatter when I get it is softer now. I've got 34 runs (combined 1/8 and 1/4) on it, and those seem to be a big reason for the smooth operation.
 

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Great news. I'm glad you're pleased with yours. Mine's worked out well. I have noticed a slight change in the engagement/release point. Before it was right up at the top of the pedal. Now occasionally I'll roll a bit lower in the range and then it's full on at the top. Hopefully won't get in the way on track days :) Probably just and adjustment and I'm not seeing it every time so I'll continue to pay attention and see what I can see. I've banged on it pretty hard for the better part of a year now w/o problems.

HemiSam
 

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Looks like I'll be needing a new clutch soon almost 39k. Let my daughter drive it, when she backed out of a parking space smelled a little smoke. Then when we got home she still smelled some smoke. Going to look into prices for the same one Hemisam has.
 
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