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n2oracer
12-19-2005, 03:00 PM
I'm helping a friend with his 79 Camaro. It has 355" hydraulic roller motor with E-Tec 200 heads. It also has a 100HP plate kit on it. It has ran a best of 12.05/109 with a 1.60 60' on motor only. The car has 295/65-15 MT drag radials, 4.10 gears, and C/E j-bolt traction bars. The car hooks good on motor at 16# air pressure, but we're having some traction problems when using the nitrous. The car has to be footbraked to about 2200 rpm to leave good. It hooks hard on motor but blows the tires off on the spray.

The bars have about a 3/4" gap to the spring. Most of that is used up footbraking the car. The snubbers are bottomed out and cut as short as possible now. Do you think more gap will help plant the tires when using the nitrous? Can you use the j-bolts to get more gap? Should the j-bolts be replaced with u-bolts? I've seen the snubbers replaced with bolts before. Should we do this and add more gap to allow the bars to have more "HIT"? What are your thoughts on tire pressure? How low would you want to run these tires?
Jim Filipowski
12-19-2005, 09:10 PM
How heavy is the car?
n2oracer
12-20-2005, 08:21 AM
3400 lbs
jshiver
12-20-2005, 09:15 AM
I had the same problems with a 1975 Camaro with a 406 ...basically the same set-up...I took the easy way out..I installed a digi-set timer, set-it on .2 out and let the tires down to 14 psi and it LIKED IT :wink:
Jim Filipowski
12-20-2005, 02:36 PM
I had the same problems with a 1975 Camaro with a 406 ...basically the same set-up...I took the easy way out..I installed a digi-set timer, set-it on .2 out and let the tires down to 14 psi and it LIKED IT :wink:

Your right.....3400lbs = 14psi
Delay the nos
n2oracer
12-20-2005, 04:14 PM
14 lbs cold or hot? We are using 16 lbs cold, about 17 lbs hot.
jshiver
12-20-2005, 05:08 PM
14 lbs cold or hot? We are using 16 lbs cold, about 17 lbs hot.
14 psi cold...pressure will build during the burnout
jshiver
12-20-2005, 05:11 PM
12-14 psi cold is the sweet spot for these cars with similar specs...I found that I needed around 14 to add the nitrous..Any lower and my car seemed to "blow the tires off" at the hit...This was also on marginal tracks...(compared to national event tracks)