hello all, I want to do a "good thang". I am building a strong Ls/Vtec setup. I will be pushing some solid air with a modified [mangled] B18C1 intake and Type R valve train + camshafts. Bowl /seat/chamber work. I am starting the exhaust with a long pipe 4 into 1 "Dynatech" header with a 2.5" collector.
This setup is going into a 91 hatch. I want to get ideas about the exhaust back from the header. I need ability to absorb engine punches. I have to use a cat converter.
This will be a daily with "mad" stealth ability when I need some extra "candy". Should I go up to a 3" cat to slow down the velocity for exhaust cat cleansing? or should I reduce from 2.5" to increase the speed and get through the cat? I am stymied by my own ignorance. All ideas greatly appreciated.