Corvette Performance - Opinions on what went wrong last runs of the season.

:usa: Here is the set up. Mid November I added a Thunder Racing cam to my Mods list. My complete set up is as follows.

Melrose LT headers with Random cats and X-pipe.
LS6 intake with throttle bypass.
Nylon ported Maf ends.
Vararam VR2B.
Thunder Cam 230/224 575/565 on a 111 LSA and Patriot dual springs.
LS1 edit, not dyno tuned.
BFG DR's

Previous best before cam was 12.20 @ 114 60' was 1.8. I went to the track and completed one shake down run shifting at 5800 RPM and launching at 3K. This yeilded a 12.38@115.3 with a 1.97 60'.

The next run I decide to move the RPM to 6200 (since I now have dual springs) and run hard and see what happens. This yielded a 12.27@114.8 with a 1.89 60'. I noticed a different sound from the motor on the 2-3 and 3-4 shifts. Sounded like the clutch was slipping.

The final run I let the car sit for an hour and lined up agian. Did the my burn out the lined up and launched. The clutch did not hold on the 1-2, 2-3 shift at all. The 60' for this attempt was a 1.98. This totally :confused: me.

Since this time I have put about 1500 miles on the car and on the street and street tires I have not had any clutch issues. So I am wondering if the stock clutch is overcomed by the additional HP and drag radials or did I just get the clutch hot and it did not cool down?

So what do you guys think?

Thanks in advance.

Curious to what sound you where hearing. If you have the stock clutch, chances are it can't handle the added horsepower. Then it would slip/spin the clutch.

It would feel like you were launching the car in water, spinning the wheels and not going anywhere. Not sure to what the noise could be.

I'd say at your added power level(which by the way, you really need to get your car tuned on the DYNO) you could easily overpower the factory clutch.

The best I can describe the sound is the engine not under full load after a shift for the first few seconds. Did not watch the tach, if I did it would answer a few questions I am sure.

The best I can describe the sound is the engine not under full load after a shift for the first few seconds. Did not watch the tach, if I did it would answer a few questions I am sure.



Sounds like the motor was bogging.....due to the clutch being weirded out. Kinda like if you were spinning, and the car was trying to grab traction but, just barely spinning the tires.


Anyways... it's your clutch dude. Pretty certain of it.

Get the car tuned before you even think about going back to the track.
I'm also wondering what made you go with a reverse split cam? The LS1/6
motors respond way better to a traditional forward split cam. You are probably going to need to upgrade the clutch also. IMO, tuning is a must after any cam swap.

Jimbo