Now, this may be somewhat of a repetative question in the forum world, but what diameter (on a single exhaust) do N/A builders use when their car ranges between 250-300whp.

***Keep in mind that going big (3inch) is not always better in an N/A motor. Under the theory of the temperature of the exhaust gas cooling down due to the large pipe ID, when the exhaust gas cools down, it becomes denser and heavier, and harder to push out the exhaust, creating a form of backpressure. When smaller ID exhausts are used, the exhaust temp stays hotter, keeping the gas less dense and and lighter, being pushed out of the exhaust quicker and easier.

I'm thinking that the optimal exhaust ID for a 250-300hp N/A motor single exhaust may be about 2.5 inches.

Has anyone ever expiremented with different diameter pipe sizes on a 350z/g on the Dyno?

 

enjoy

 

thanks hooper

 

no prob, hope it answers the q completely

 

2.25 is a good size for NA and also FI up to around mid 400ish.
I only have 2.75, but will be good to 600whp.

 

After a few tries with custom piping/exhaust systems with the Z, i feel 2.5" is optimum for N/A. The stock piping is 2.36" so around a 1/4" up with a single exhaust would be good.