I figured it had to be something.
Have those heads CNC'ed and you could be looking at another 40rwhp.
They are. They have been ported by TEA and flow quite well. But I am running a small cam, small exhaust with cats, and I could be having fuel pump issues. Fuel pressure drops throughout the run.
Next up is a .600+ lift cam, 1 3/4 headers, and 3in exhaust. Maybe do some changes with the suspension. Right now its setup for more road coarse. Tociko 5-ways front and rear, solid control arms, Kenny Brown full matrix system (double cross subframes, jacking rails, seat braces). Car cuts horrible 60ft's and spins mad in second gear. Car should run 11's right now but traction on the Nitto DR's is weaksauce.