L31MaxExpress
I'm Awesome
Funny thing 10+ years ago after flowing a set of the Mexican ones and getting piss poor results I was told I was wrong. Also had decent results from the 305 Vortec heads.Ya he flowed original vortecs, 305 vortecs, and the OTC Mexican vortecs GM still sells. Basically the OTC ones flow the least, therefore get used original ones and have them checked out or buy aftermarket aluminum ones.