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Old 01-19-2013, 11:32 AM
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CHEVILLAC, in case I wasn't clear on my recommending you use the small Edelbrock carb, this is to get the engine up and running. If the carb is in good shape, you can basically bolt it on and w/a possible/probable change to the step up springs, you'll be able to at least drive it to see what else is needed.

I always advise guys to first set the distributor up w/a performance timing curve, before tuning the carb beyond adjusting the idle mixture screws and the curb idle speed.

A performance timing curve for a stock GM HEI consists of lighter mechanical advance weight springs (the weights are usually OK as-is) and limiting the mechanical advance to about 10-15 degrees. The rest of the timing (about 20-25 degrees) will come from the initial timing. Details are at the link I added several posts ago.

I seldom recommend locking the mechanical advance out so it doesn't work, but in this case- w/the cam as big as it is- you can do this to get it up and running. Then later on you can go back and set it up w/a curve if you want to. This is easy to do but it may require an ignition interrupter switch be installed so the engine doesn't kick back against the starter when you start the engine (locking the mechanical advance and the interrupter switch are also covered in the link). I'd use about 32 degrees timing to begin with- not optimal, but enough to see what you have. This isn't what you want w/a high rear gear, but as long as you don't mat the throttle from a too-low rpm you should be OK. If you hear detonation though, you'll need to back off the timing, back off the throttle/load on the engine, or add the curve I talked about above.
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