SamJLee
New Member
Ok I have megan shorty header, greddy sp2 exhaust, but I still have my stock cat converter there. I've been thinking about the air flow and dont know if it should be ok. The way I see it is my header is alittle bigger than my stock ones, than the air passes through the cat converter, but than the piping is smaller. Than finally the air goes through my exhaust which is again bigger than my stock one. Is this fine, all the different piping diameters kind of gets me thinking.