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Author Topic:   NEW 400 owner
posted July 26, 2001 02:15 PM
I think if your cut the deck to 0 and use a thin steel gasket of about .016 you will likely make contact with the heads.I would say .038 deck would be a min. to keep it safe.Don't forget to check piston to valve clearence.Most guys don't drill steam holes on race motors but you have to on daily drivers.I would go to 5.7 rods to get a better rod angle. You will break the 5.565 rods if you turn the engine at all.

posted July 26, 2001 06:49 PM
I know a few people who run the 400's and they dont seem to have a problem with overheating. One of my buddies run a 400 sbc and his engine builder plugs off the steam ports in the heads because he says they crack from the chamber to the steam ports. Has anyone else ever heard of this?

posted August 02, 2001 08:01 PM
I was not saying he should plug them, I was just asking if anyone had ever heard of anyone else pluging them, because until my buddy told me about his and I had never heard of it.

Red Dog
posted August 08, 2001 05:43 PM
95% of the 400's we build have the steam holes (in the block) plugged. The other 5% don't wanna spend the extra few bucks.
As far as plugging the steam holes in the heads - very seldom do you find a 400 head that's not already cracked across the center exhaust seats. Usually use a 350 casting.

posted August 09, 2001 04:19 PM
the steam holes are not needed if the engine
will be primarily run above 3000 rpm as the extra pump flow will purge steam pockets,this
is according to the chevrolet power manual,
never drilled the holes in my 292's no probs in 4 years.however I use one to one pulleys
not underdriven may make a diff.

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