Got my 1971 31,000 318 apart....any comments appreciated

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LXguy

LXguy

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Well, got the heads off it at least. Looks like the bores are in pretty decent shape, or at least for something that has no doubt spent a lot of time sitting.

Looks like it does in fact have the skinny head gaskets from the factory. FABO is right again.

Who's the genius that designed these small block Mopar heads so that you can't stand them on end?

Pistons are .080 in the hole! Sheesh.:thumbdow:

Assuming a 64cc head (haven't measured it yet) that puts my compression at an awesome 8.5:1. One of the Mopar small block hot-rodding books claims 60cc, but they haven't been right yet.

With a 58cc it still only gets up to 9.14, and obviously has no quench to speak of.

I wonder how well the head gaskets would seal if I cut the heads down to 54cc....

What's the best way to block the heat crossover? Looks like the gasket blocker deals burned right through.

Steve
 
To block the heat cross over, use a sqaure metal tab and insert it when you put things togther. Thats what Ma tod us to do.
 
Something like a flat piece of tin? Do you just pin it in place with the gasket or something?

Thanks!

Steve
 
Yes, thickness shouldn't be to much since it's gotta seal up. Mopar used to sell'em. I'd just place it on the head side of the gasket. That'll do.
 
Thanks for the info!

I'm trying to decide whether to run this intake or the LD4B. I need the engine to make power to 5500 RPM.
 
You can mill .100" off them. I made a set 54cc IIRC. You will need shorter pushrods tho.
 
If your taking the whole motor apart, deck the block, measure center of mains to top of deck, good chance the block as an extra .080 on the top.....
 
Check with your books. I think Mopar changed the 318 piston in 71 to lower compression. The 67-70 piston, I think comes closest to the deck. This will give you a bit more CR if you're planning to take the lower end apart.
 
70-71 engines are rated for 8.8:1 from the factory. They run on the cheapest crappiest gas out there...I know I used to run 87 in my original engine all the time.
 
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