** YOUNG FRANKENSTEIN ** The truck Chevrolet should have built.

[thor]

Originally Posted by drewskiren

I have been doing a little more research on my engine and found a Car Craft article about the best flowing exhaust manifolds for LS engines.

http://www.carcraft.com/techarticles.../photo_03.html

I don't want headers for many reasons - cost, heat, noise, poor quality, etc. and after reading this article I am totally sold on these 2004 -2006 GTO LS1 manifolds. The article calls them Corvette manifolds, but is wrong if you look at the ones pictured - they do mention once they are from a GTO. Anyway, they are within 3 or 4 HP and torque of headers, and 9 HP and Torque better than the next best factory exhaust manifold, Camaro style. I am sure the truck ones I have are probably a little worse than that. I'm on the hunt now for some GTO take offs. Maybe $30 to $50 bucks. Way less than headers and nearly the same performance. Hoping they will fit.

Looks like I may have to do my exhaust a third time! It won't be too bad though.

These manifolds are kind of a Tri-Y style. Cool! Hopefully they'll open up the exhaust like the Doug Thorley's.