hi, i'm in the process of building a 383 with approximatly 475-500 flywheel hp, this will also have 100hp shot of n20 at call for a total of 575- 600hp......

my question is will a dual 2.5 exhaust be able to breath freely through this???

i wanted to use hedman universals extensions and a flowmaster h pipe crossover, but i cant get the extension bigger than 2.5....

they will be flowing throught 2 40 series flowmasters!!!

heres a pic of what it will look like...

 

I would think so, but I forget the charts, there was a graph a while back on here with HP and piping size needed. Maybe try a search.

 

I beleive that will be sufficient, but I'm not an expert. Any more hp than that and you might wanna bump it up some.

 

thats a pic of my car. that set-up performs like a champ with my 383 (engine analizer came up with 479hp) not sure if it will suffice on the juice or not.