I am about to go single with a 500r, and I have a rx7store high flow cat with down pipe and N1. After I get the turbo put on, I want to get a racing beat dual catback. Will there be a loss in power. Should I replace the highflow cat, with a res midpipe?

 

Go rx7 store resonated midpipe w/ the rb dual. I switched from the Pettit resonated to rx7 store and gained a few horsepower at the same time queiting it down some. Dont know why but did. If you are going to keep both catbacks compare horsepower on the dyno. I heard the rb dual is not restrictive but hard to believe it wouldnt rob a few horsepower. Anyone chime in on dyno comparison betwen a freeflowing single tip and an rb dual?

 

500r - I'd go 4" all the way back...put a res in there too. with a custom 4" muffler.

 

Basically that is what I did.

 

I don't know if this would change your advice at all, but I am on stock ports.

 

doesn't a-spec recommend porting with that turbo?

 

pull motor and complete project appropriately.