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Discussion Starter #1
I'm wondering how agressive a cam I could use on my 350 if I use 305 heads? Would the stock pistons work? Somebody must have done this. Bank balance (or lack there-of ) prevents buying the heads I'd like to put on it. I'm going with headers and a Holly w/ intake. (no smog) Any thoughts?
 

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The 305 heads will work on the 350, but you would see a better performance gain if you use the stock 64cc combustion chamber bigger valved heads. As far as the cam goes, that would depend on whether you plan on driving the car daily or less...the bigger the lift and longer the duration of the cam, the less streetable the car becomes. Bigger is not always better. You want to think this out carefully, you want a cam that will best perform in the RPM power range you'll operate in to produce the most torque in that RPM range. If you build your engine to produce the most torque above lets say 5000RPM you want a high lift long duration cam. If you want it to produce it's max torque in the 3500-5000 RPM range you want less duration. Most cam companies will list which of their cam works best in what RPM range. Thats where you need to make your decision. As far as pistons go, are we talking about using stock flat top pistons or dish pistons. Flat top will give you about 10 to 1 compression ratio whereas dish will lower it to about 9 to 1 with 64 cc heads. Or you can even get stock domed pistons from the original 1970 350 LT1 engine, that would give you 11 to 1 compression (serious racing only) but you don't really want to do this if you drive the car on the street...AT ALL. The unleaded gas will cause some major problems. Plan your engine out carefully for what you want it to do, before you start buying all kinds of parts for it. It's very easy to build a 400+hp 350 that'll run on 92 octane gas, for a reasonable amount of money. But you won't accomplish this with the 305 heads, you'll need something better.

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Discussion Starter #4
Thanks to both for the quick reply. Looks like I'm going to stay with the 350 heads. Since I'll be sending the block to the machine shop, I'm planning to go with the flat pistons. Now, to just figure out which cam. The car will be driven mostly on week-ends, and occationally during the week, as weather permits. Other times I drive my plain 82-229-700r4. Now to research the cam Companies. BTW, project car still has a high gear (to be changed one day), and a 700r4.
 

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The 305 heads chambers are much smaller than a 350's resulting in a sharp edge that overhangs the cylinder. The edge should be rounded off or hot spots that cause pre-ignition(detonation,teaketteling) will be a problem. The compression will be high from the 305's 58cc chambers.
 
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