So I was browsing a summit catalog today......

[gnfanatic]

And noticed alot of the muffler's showed a cfm rating. Like the dynomax 3In "flows up to 410 cfm". So if you turbo flows 1200 cfm and you have an exhaust that flows 820 cfm arent you going to have massive back pressure???? Are these mufflers very restrictive or am I not understanding it?

 

[BOP4ever]

You have to know the test pressure they measure that out to make sense of it.