Thread: 300hp fuel injected sbc for under a grand? Is it possible?

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you will have no trouble getting 300 horsepower with those double hump heads. factory 327 with those old style heads was getting 375 horsepower with the old fashioned mechanical fuel injection in 1964. you will have slightly smaller valves and less compression but more cubic inches so well over 300 horsepower is doable.

Hi,
I've got some experience with successful TBI HP mods, I'm on my second modded vehicle. I've heard good things on Vortec heads but haven't used them yet, I'm putting a set on a marine mill now. I'm running 180 cc runner RHS heads on a 9:1 383 stroker with really good results. I used the 68 #/hr "cop car" injectors and a TPI fuel pump, i modified the fuel pressure regulator to make it adjustable currently the pressure is 20psi. The manifold is the Holley projection 2" bore one, I've heard really bad things about the Holley tbi unit, and I had a 350 one bored out to 1.930" from my last vehicle 1990 full size Blazer and it works great. I had to hog out the center 4 bolt holes in the manifold to use the early bolt pattern on my heads. The cam is a hydraulic roller from Comp Cams with 210/218 duration at .050" lift and if I remember right a 113 degree lobe separation, lift with 1.5 roller rockers is around .5", (comp cams actually recommends 1.6s with that cam). I ran Stans headers into a high flow cat and 3" single exhaust. I retained EGR buy plumbing 1/2 copper with a heat shield on it, from the EGR fitting in the headers into a compression fitting just below the egr valve in the intake manifold, (no heat passage provision on the heads). most importantly i had a chip burned by Brian at Harris Performance "TBIchips.com" which optimized the package. the vehicle is a 1992 full size Blazer 4X4. The problem is I've built something I'm afraid to open up, my nerves give out at about 4000 RPM in second gear. That cam has a flat torque curve and shows no sign of running out of power shifting at 5,000 RPM. I would like a little more power below 1,500 RPM, it really kicks in as it approachs 2,000 RPM. I'm running it strait up. Excelent for towing and I'd like to get it to Englishtown just to see what she'd do, probably mid to low 14s. It does lack that peak power feeling that a cam 2 sizes bigger would give in the higher RPMs.