Copper head gaskets ?

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AdamR

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Are copper head gaskets ok on the street ? Looking at a set of .093" thick gaskets to lower my compression from 11:1 to about 9.5:1
 
Adam, you running domes on those pistions? I dont think you will take 1.5 out of the compression W thicker gasket.
 
Flat tops with a + .020 deck height, 60cc chamber head and a .039" gasket.

Compression calculator said from 11:1 to just over 9.5:1 going from the .039 thick 4.180 bore gasket to a .093, 4.155 bore gaskets.
 
Copper tend to be a little seepy , they are so hard of compound , you would need to use some type of sealer to ward off a potential leak . Maybe you could try cometic .
 
Cometic require a smooth finish on the deck that would require taking the motor a part and having it re cut. If I have to take it all a part I would just have a new set of pistons made.
 
That much gasket will kill your quench effect. With +.020 deck height and .093 gasket, gives you a .073" quench and this will cause your engine to be detonation prone. You would be better off using a zero deck piston and a .040 gasket. 60 cc heads? Are these 318 heads? Wedgehead1
 
I would stay away from the copper head gaskets. If you’re running the motor hard and something has to give, would you rather replace a blown head gasket or an entire engine?
 
I think with some spray copper on both sides, you'd be ok. Torque it carefully, make sure it compresses evenly. I think it will be fine.
 
That much gasket will kill your quench effect. With +.020 deck height and .093 gasket, gives you a .073" quench and this will cause your engine to be detonation prone.


Thats another thing that worries me. I would be going with a smaller cam at the same time and may end up with just as much cylinder pressure. I had a iron headed 440 with pistons .090" in the hole (TRW L2266Fs) and milled heads thin gaskets for compression. Even with a 244 @.050" cam on a 108lsa it would detonate with out race gas. Of coarse now Im older and a little wise (just a little) and I dont think I had the detonation problem till I changed the distributor and the car started running warmer.

Maybe I just need a second car. 1 race car 1 street car, LOL
 
Sort of off and on topic, but just read an old article in Mopar Action about their flying brick as they called it. Really nice car. Anyway, Ray Barton used copper head gaskets on thier engine. Small block stroker I believe, but could be wrong there as I was just reading a bit here and there on the article. I do know though that he O ringed it. Don't know if this was his standard practice, was due to their application or was due to the copper gaskets on a Mopar need something like that.

On the other hand, this is where it gets a bit off topic, classic Minis have used copper head gaskets for years. The classic Mini does have a 2-3 trouble spot between the cylinders, but many, many have run years on a copper head gasket with no problems. Comes down to quality of build and correct head torque etc. Compressions on some we've run have been up in the 11 to 1 range and all run a high rev band with no problems. I know it is a different engine etc., but just an example. EDIT: Oh, at least on this application, using a copper head gasket we use no sealants etc.
Cheers
 
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