Professional Answer to Exhaust Size Question 2.5" vs 3"

Dustedu2 said

I asked
("I am installing a 422 stroker in my Duster. About 520HP with TTI Headers. Will I benefit from a 3" exhaust vs 2.5") to an exhaust manufacturer and got this reply:

"550hp would be the minimum for 3" unless you were building a race car."

I still want the 3" so I will probably go 3" anyway.

Click to expand...

One thing lots of folks dont know about pipe is that it has internal drag or friction. The bigger the pipe the more friction created. Just like a car trying to "push" thru the wind,now the exhaust is the wind and it's moving instead.I have no clue where the break even point would be or if it really matters in your situation. Probably not unless your looking for every last h.p.

A bigger pipe will add more weight too.

3" is probably not neccessary but it's what you want so...go ahead and do it!