Author Topic: bbc head gasket question  (Read 2675 times)

Offline crider

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bbc head gasket question
« on: May 14, 2016, 10:30:11 AM »
I'm working on getting the engine for my FED project wrapped up. It's a 4.375 bore 3.75 stroke engine. With steel rods. I was reusing some of my leftovers parts from other projects, and I have about .010 positive deck height on the pistons. So I'm trying to decide what thickness head gaskets I want. What do you feel is the minimum piston to head clearance that is safe?

Offline Frontenginedragsters

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Re: bbc head gasket question
« Reply #1 on: May 14, 2016, 06:42:00 PM »
Hello Crider:
 Typical piston to cylinder head clearance should be about .040"
The piston or rod will not stretch anywhere near that amount but the piston will "rock" at TDC.
The more piston to wall clearance you have will allow more of this "rock" to happen.
You might be looking at using a MLS gasket [multi layer steel] or copper.
Put the piston at TDC and see how much you can push down on the spark plug side. See how much it sticks up on the other end.

Good hunting: Matt
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