So i have a 1970 318. the other day a nut on the POS edelbrock air cleaner housing worked its way loose and fell through the carb, down the intake, and got settled in a valve. when after pulling off the intake and attempting to remove said nut, it fell in the head. It's a brass nut, so it wont stick a magnet, and i cannot get the nut out through the sparkplug hole. So I'm going to have to pull the head.
Will i have to pull both heads and replace both gaskets, to ensure that the gaskets are the same thickness?
I have read the different gaskets can affect compression. It's a stock motor. Would there be enough of a difference to cause problems?

Things learned so far:
Flatten all threads
Don't use brass nuts.

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What's that fuzzy blue thing being hurled this way?
::stick::
BOOSH!!!

If the 318 is anything like the original on in my '70 Swinger, I can tell ya from firsthand experience you are thinking way too much about this. Chrysler didn't care enough to make sure the bores were all the same size on mine (pretty common) and I wound up rebuilding the whole motor. You probably can't buy just one head gasket and you'll need an intake set anyway, so just get a valve regrind kit and reseal the whole top end. Then, after you get tired of the blue smoke from the tailpipe you can tear it all down and build a real motor. In my case I wound up wrecking the car in less than spectacular fashion, but it ran great up until then!

-James

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