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Old 01-18-2013, 06:32 PM
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Quote:
Originally Posted by CHEVILLAC View Post
I don't want to blow it up but I really don't have a lot of money to invest in it either. I think I'll rebuild my q-jet, put it on the motor, put the motor in with a 3000 stall and see what it feels like. Then when I can save some money I'll put the 3.73 posi setup in the rear and my 29"x10" pie shell cheater slicks and head for the track. Does that sound reasonable?
If you're going to use a Q-jet, the amount of vacuum the engine makes has a direct effect on what spring to use for the power piston. Too much spring/too little vacuum will have it running pig rich (will be always on the power circuit) anywhere except WOT. Same concept as the power valve on a Holley or the step up springs on an Edelbrock/Carter.

Depending on what the Q-jet carb was originally from, it may need other changes (APT adjustment, jets/rods, bypass air orifice size, more idle fuel, to name a few). I don't say this to dissuade you from using it, just want you to be aware of the possible pitfalls.

Again, for the purpose of getting the engine up and running: Use the Eddy and a dual plane. Use a properly set up distributor.

Once you know what the idle vacuum is and how the cam is, then you can go about tuning it for real.

Also, the cam is the big unknown. It might be any sort of cam. Depending on what class it was built for, it could have a stock lift cam (often they'll have a ton of duration), it could be a cam ground for a vacuum rule, it could be set up to intentionally loft the valves off the nose of the cam lobe to circumvent the rules, could have hydraulic lifters on a solid cam (or vice-versa), it may be excessively advanced/retarded, et cetera.

If you cannot get a straight answer on cam specs/grind number from the guy who owned the engine, you really should take the time to measure it or see if there's some ID on the cam- whatever it takes. Because the way it stands now, you're (and we're) totally in the dark. This makes giving meaningful recommendations a total crap shoot.

3500 stall on the street is not as bad as you may think. But again- w/o knowing what the cam specs are, picking a stall speed is a total guess.
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