What were you using for parts to do this with tbi heads? I've got the motor out of my 95 and trying to figure out what I'm putting back in. It blew a head gasket between center cylinder on drivers side and ate a groove in the head and block. I was bummed out was drilled for a roller cam. 95 k2500 sclb 410 gears 5.7 4l80. I want it to sound good and pull good. 300hp and 400 ftlb at crank would make it a fun driver. I run 100 miles a day on 75mph freeway with it and high teens would have me clicking my balls together lolI was able to get similar power with the stock heads and 20 mpg @ 70 pushing a brick into the wind. I do not know why you claim that....TBI engines are most restrictive in this order. Exhaust, Cam, Intake Manifold, then TBI.