I was trying to purchace a set of 1-5/8 w/o AIR shorties from thunderracing.com, but SLP no longer manufactures them. So my next option was 1-3/4 w/o AIR shorties, but i am affaired that they might be to large for my mostly stock set-up, and if a remember right, people have had fitment issues with the 1-3/4 shorties.

-current setup
85 Z28 IROCZ
stock 305ci TPI
3" dynomax catback
150 shot
PI converter
ProBuilt 700r4

the only thing for this car in the near future is for my to replace my leaking intake w/ SLP runners, large mouth base, ported upper plenum, 52mm TB, and since i will have the whole intake apart i might instill a larger cam. something like COMP's NOS cam 218/230@0.460/0.483 lift.


But even with my current mods and future plans; I still think the 1-3/4 headers will be way to large, and i am concerned with install.

You wont lose any power from putting a 1 3/4 header on your car. As for the fit all i had to do was put a small demple on one of the driver side primaries and bend some break lines out of the way.

I think 1 3/4" is a little big for a 305. Try for some 1 5/8".

91RS5speed- can you post any pics of the small dimpling of some shots of the header in the engine bay? thanks.

i am sticking with SLP, i no longer have any AIR equipment and SLP no longer makes 1-5/8 w/o AIR.

any reason you are sticking with SLP?

factory quilty parts, the have the thickest flang, 409SS not mild steel, and the 1-5/8 fitt very well.