New solid cam installed
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From: 53.0907° N, 113.4695° W
Re: New solid cam installed
Digging through my books looking for primary tube calculations and I found:
Based on your exhaust port flow at max lift; 160 CFM @ .500"
Purpose of the vehicle; drag racing where maximum RPM is seen most of the time (lowest RPM is 75-80% of the max)
A 1 5/8" I.D. header is said to be able to do the job.
The variable here is you've added nitrous which typically calls for more exhaust everything.
FWIW. There may be gain on the exhaust side with a 1.6 ratio rocker if performance on N20 is more important than not. Same might be said for a larger primary tube but the text books say 1 5/8".
Based on your exhaust port flow at max lift; 160 CFM @ .500"
Purpose of the vehicle; drag racing where maximum RPM is seen most of the time (lowest RPM is 75-80% of the max)
A 1 5/8" I.D. header is said to be able to do the job.
The variable here is you've added nitrous which typically calls for more exhaust everything.
FWIW. There may be gain on the exhaust side with a 1.6 ratio rocker if performance on N20 is more important than not. Same might be said for a larger primary tube but the text books say 1 5/8".
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Joined: Aug 2015
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From: Columbia, SC
Car: 1989 Camaro RS
Engine: 383
Transmission: TH400
Axle/Gears: 9 inch, 35 spline drag spool,4.56
Re: New solid cam installed
Digging through my books looking for primary tube calculations and I found:
Based on your exhaust port flow at max lift; 160 CFM @ .500"
Purpose of the vehicle; drag racing where maximum RPM is seen most of the time (lowest RPM is 75-80% of the max)
A 1 5/8" I.D. header is said to be able to do the job.
The variable here is you've added nitrous which typically calls for more exhaust everything.
FWIW. There may be gain on the exhaust side with a 1.6 ratio rocker if performance on N20 is more important than not. Same might be said for a larger primary tube but the text books say 1 5/8".
Based on your exhaust port flow at max lift; 160 CFM @ .500"
Purpose of the vehicle; drag racing where maximum RPM is seen most of the time (lowest RPM is 75-80% of the max)
A 1 5/8" I.D. header is said to be able to do the job.
The variable here is you've added nitrous which typically calls for more exhaust everything.
FWIW. There may be gain on the exhaust side with a 1.6 ratio rocker if performance on N20 is more important than not. Same might be said for a larger primary tube but the text books say 1 5/8".
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Joined: Sep 2014
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From: south central Texas
Car: BUILDING 1985 HARD TOP T/A
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Axle/Gears: GM
Re: New solid cam installed
I would call your head Porter, see what he thinks. Not, up to date on your build/spec's so any recommendations wouldn't be relative to it.
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Mar 15, 2008 10:46 PM