Somebody gave me a short block from an '89 IROC-Z Camaro. Block has the fuel pump boss and the hole is drilled for the pushrod. Roller cam is pretty tame but has the eccentric for the fuel pump that has never been used since I guess it was a fuel injection car. Everything is in really good, serviceable condition. Figured I could put some 1.52 or 1.6 rockers on some good 462 heads I have and put the thing in one of my beaters and see what happens. But I'm going to run a carb and want to run the mechanical fuel pump. Don't know what fuel pump pushrod to use. Seen everything from the nothing special stocker from any SBC to bronze tip to roller tip. I have no idea why this thing had the fuel pump eccentric and what the GM engineers had in mind here. And what about the distributor drive? I grabbed the gear off a low-perf roller cammed '92 Camaro distributor, but it looks like any other gear. Any ideas?
'85-'88 GM used roller cams and carbs. 85-87 Monte Carlo 305 was a roller cam and used an E-Q-Jet. FS trucks used roller cam and carb 305/350 in the same era until the '87 and newer body style kicked in and then they went TBI. Think you could still get a 305/350 Qjet on a F body til ~'86 So it is a normal production engine. Install a pump pushrod for a '87 MC SS and it should be fine.
Several years ago I bought a 305 from a wrecked 92 Camaro. It had TBI and I installed a carb and mechanical fuel pump. Idled fine but would run out of gas while driving. After a lot of hair pulling and parts replacing it turned out to be the eccentric on the cam was not fully ground for a mechanical pump. Had enough movement for the fuel pump to fill the carb at idle but enough to run down the road. Finally installed a flat tappet cam and installed one the fuel pumps that was on it earlier and problem was solved.
Yeah, the 3704817 Johnny put the link in for seems to be the one. That’s the one GMPP specifies for the ZZ4 crate engine with a factory roller. Maybe over thinking this for a low buck what the hell build...
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