Thread: Quench Questions

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I would be more concerned with brinelling (fretting) the aluminum heads using a thin steel gasket. Airflow Research recommends the Fel-Pro 1003 with their heads on a 350, so that's what I would use on AFR heads. They're 4.166" X 0.041" and you're correct, the squish won't be ideal until you cut the decks for zero piston deck height. Will you get by with it? Yeah, with aluminum heads and 9.65:1 SCR. Will it be as good as it could be? No.

David Vizard runs his motors at 0.035" and has said that he picked up power all the way down to that point. I suspect he would go tighter yet, but might be concerned about experiencing a piston/head collision.

You didn't say the manufacturer of your heads, but bottom line, use the gasket recommended by your cylinder head manufacturer and tailor other engine parameters around that (like cutting the decks for better squish).

Hey Tech, thanks for the reply. The heads are Patriots. They reccomend using FelPro #1004 that have a compressed thickness of .041". When reading about quench it seemed that high quench (.069") is considered distructive i.e. major detonation. I really don't want to zero deck the block for this build unless I need to. It has already been squared/leveled.

"It has already been squared/leveled."

Apparently it hasn't been squared/leveled enough to get a good squish. You are the owner of the parts. You can do with them as you wish, but if they were mine, I'd make certain everything was right before I began screwing bolts and nuts together. What's the compression height on your pistons? A good 350 piston should be at 1.560+. If the pistons are at that, I'd cut the block decks to zero. If the pistons are short, getting the correct pistons would put you a little closer. I personally wouldn't mind so much being at 0.050" with aluminum heads, but that's where I'd draw the line. All top builders will tell you the same thing.....0.035" to 0.045". David Vizard currently uses 0.035" and I don't think there is anyone on the planet who has more dyno time on small block Chevies than he does.