I have 2 sets of headers for my 302 1 set has 3 inch and my exhaust is 2and 1/2 the other ones are 2 and 1/2 does it matter witch ones i use
how big are tubes at the heads and make sometimes it does make a diff also whats motor or in it?
the set with 3 inch ends came off a mustang the other ones not sure I think off a truck
if you're running a full exhaust system it shouldn't make any noticable difference. the larger collector would probably move your torque curve up a few 100 rpms,while the smaller collector may make a little more torque @ a lower rpm, but lose a bit of hp .
I am gonna run stacks in the bed