I am going to have some light work done to the factory heads, a mild cam, a carburetor and transmission work done. I want to put shorty headers (due to clearance) on and I saw some are 1.5 dia. and some are 1.625. The 1.5 dia. are JBA's and the 1.625 dia. are Pacesetter. Does the diameter help or hurt for a slightly modified motor? Does either company offer a good piece?

Thank you, Chris