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Originally Posted by Mertz
I have been reading up on head gaskets because I am almost to the point of putting on the heads on my 283 build. I know the pistons are shorter than stock. I have decked the block and the heads for a total 0f .017 (.010 block .007 heads). My kit came with a composite (cheap looking) head gasket and I don't know what the compressed thickness is. I am guessing .041. I have read that we want a quench of about .041. Doing the math, if I use the .041 gasket I will have a quench distance of .056. Is that too much?
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While 0.035" to 0.045" is considered by many to be ideal, the motor will work fine with a slightly wider squish of 0.056" in my opinion.
Quote:
Originally Posted by Mertz
Also if I use the composite gaskets do I spray them with copper seal or put them on dry?
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Clean all foreign substances off the block deck, heads and gaskets and install them dry.
Quote:
Originally Posted by Mertz
What is the best head gasket to use?
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The best gasket to use is the one that works with your combination. With iron heads, use just about any gasket you want to. If the block decks and heads are flat, you can use shim gaskets (0.016") if the decks and heads are flat within 0.002" end to end. Composite gaskets will allow a good seal on "less than ideal" surfaces because they have the thickness to conform and still seal. Those fellows with aluminum heads have to use a thicker composite gasket (0.039"/0.041") with a pre-flattened fire ring to prevent brinelling of the aluminum.
With iron heads on a 283 where I needed a little thinner gasket, I'd use this one.....You can buy it here from Summit or you can toddle down to your local Chevy dealer and order it across the parts counter. Note that they are sold individually.
Chevrolet Performance Composition Head Gaskets 10105117 - SummitRacing.com
If your pistons are down in the hole by 0.017", these gaskets will yield a squish of 0.045".
One part of engine assembly that always makes me grit my teeth is the installation of the intake manifold. If the block decks are not parallel with the main saddle on all four corners, the heads will not sit squarely on the decks and the intake manifold will not seal the same all the way around. Pay very, very, very close attention to the intake gasket seal. I have even sacrificed a set of intake gaskets by installing the manifold, torquing to specs, letting it sit overnight, then removing it to inspect the gaskets for being pinched ALL THE WAY AROUND EVERY PORT. If you put the motor together with an internal leak at the interface of manifold and heads, it will never be right and could possibly suck oily vapors from the crankcase into the port and on into the cylinder as the piston descends with the intake valve open. Just PAY ATTENTION. Many builders miss this very important step.