Apr 30, 2012
2005 C6 1SB
CRG Research Report - COPO 427

Now, the ZL1 was THE top dog Chevy in 1969. The factory original numbers don't look all that impressive today. There is a lot of that old, "The older we get, the faster we were." This isn't taking anything away from the musclecar era. The new cars have 40+ years of engineering improvements, computer controls and an awful lot of hours spent on flow benches. Take a '60s L72 427, add some of the latest heads and other stuff and it will run a whole lot better than they did in '69. A friend has a 468 big block Camaro that he built himself with aftermarket aluminum heads. He drives the car on the street and the car would run with the 1969 Pro Stock cars. Being able to run 10.0s @133mph, this old car can put a long face on a lot of today's cars. The hp numbers on the ZL1 show just how badly the emissions jetting, timing, and chambered exhaust choked the engine down. I found the same thing with our COPO Chevelle. Jetting, timing and exhaust did make a BIG difference. Today, the computer takes care of the fine tuning.
CRG Research Report - COPO 427
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That is an awesome list! I just wish they could have done a test on the exact same car with modern rubber or slicks just to see how much of a difference the rubber made.
with suspension mods, open headers, lightening the car a little and 8 inch slicks, i got my 340 demon into the 12's. tuning was the key with the old dual point distributor. the stock 850 thermo-quad worked well on the car.
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