I recently installed some Comp Cams 980 springs on my 60,000 mile 87 Turbo Regal. I was having a top-end problem. My car was quick off the line, but just seemed to lose steam after the 1/8mile. With the mods in my sig, I could only manage 101mph in the 1/4 mile. I haven't got the car back to the track yet, but I can provide some real world comparison. I raced my buddies 2001 Formula Firebird this weekend from about 60mph to 110mph. I got a 1 car jump on him, and by 110mph, he had just creeped up to even with me. Here's the kicker. His car has an MTI Lid, fast toys ram-air, hooker long tube headers, offroad x-pipe, true duals, bullet mufflers, MTI C1 cam, and a Precision Industries 3400 stall converter. He has run 107mph in the 1/4, and that was before his cam, headers, and off-road x-pipe.
Here's another kicker. My car was @ 20psi, it was 97° outside, my Cat was on the car, and I had about 5°-6° of knock on each run.
The only other change I made to the car w/ the springs are 60lbs injectors. I would say my old 36lbs injectors might have not been enough for the T63E, therefore causing the car to slow down, but I had the same type of low MPH (top-end) problem w/ the stock turbo on the car.
Conclusion:
I think the 980's played a huge factor in my new top-end charge.
Here's another kicker. My car was @ 20psi, it was 97° outside, my Cat was on the car, and I had about 5°-6° of knock on each run.
The only other change I made to the car w/ the springs are 60lbs injectors. I would say my old 36lbs injectors might have not been enough for the T63E, therefore causing the car to slow down, but I had the same type of low MPH (top-end) problem w/ the stock turbo on the car.
Conclusion:
I think the 980's played a huge factor in my new top-end charge.