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I have used this sled for about three years and I've had to replace the head gaskets twise on each head and now it just blew another if anybody knows anything about these sleds please help! I think the heads might me warped but I don't know for sure I haven't taken it apart yet.
 

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Ever do a Compression check after you put on new gasket? What is it? Maybe, someone shaved the Head for higher compression. Not sure what your 440 used for compression, but 377, 380, 447, used 9.6cr. Around 120-125psi. Are you using the correct thicknest Gaskets also? Did you ever do a Squish test?
 

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I have checked the compression and it was around 120-125 but I just got the gaskets off of royal distributing for my model of everest and I don't know what a squish test is?
 

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Basically take your spark plugs out. Take some soft soldier like .080" and bend it L shaped and stick it in your spark plug hole so it reachs the edge of the piston, and pull the engine over. The Piston squishs the soldier and then you measure the thickness. I believe .050" to .060" is the range you need to be in, but check the manual for your engine. If your Compression is only 120-125lbs, I would bet you have a warped head. Check the Cylinders to see if their level across from each other also. You may have different thickness Base gaskets. If you have a smooth surface, a piece of glass works, you can put some polishing compound on it and rub the head on it, or just use some Black Sand paper 600grit on a smooth surface, and rub it back and forth to get the high spots. Look on Youtube, there are some different examples on how to do it. Some people make a threaded arbor that screws into the head and use a drill to spin it. You don't want to take to much off, or the chamber squish band needs recut.

On a 377/380 for example, that has a 62mm Bore. Taking just .030" off = .14 cubic inch or 2.294189cc and if you had a stock 9.6cr, you just raised it. A 4cc drop in your combustion chamber would make it a 11.2cr now.

Rich
 
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