back pressure, good or bad?

Trying to match an exhaust to my 292 inline six. Its got full length headers, and big cam, but im not sure if straight pipes are gonna help it or hurt it. This is the first inline project I have done so any tips would help. Thanks.

 

So true ,I know alot of guys that uped there exhaust on Grand nat's and made them slower .You definately want a certain amount of back pressure .My guess is It probably is configured into torque .........On a guess I wouldn't go bigger than 2 and 1/4 .Thats on a single exhaust system .

 

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