hey guys i have a set of ported 416s i'm going to put on my 89 lb9 5 speed iroc with a crane 2032 cam, semi siamesed base, ported plenum, msd ignition, and 1.6 roller rockers.

anyways i see a lot of people swapping over to 1.94 intake valves.

thing i was curious was has any1 swapped over to 1.6 exhaust valves and left the factory 1.84 intake valves in then flowed it?

it seems the exhaust side is super week on these heads in most all areas.

they seem to flow over 200cfm intake ported pretty easy but, exhaust is no where near the essential 80% rule of thumb.

anyways just curious if any1 could point me towards a thread i havent found about the subject at hand maybe.