Milling 587 small block head?

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gtsdude

gtsdude

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I have a low compression 73 340 and was thinking of having the heads milled to gain a point of compression. My question is has anyone know how much is needed to be milled to gain a point assuming they are at say 72cc now? I will have the heads cced and measure how far down the pistons are to get my compression ratio to
Start with, I am hoping it is at least 8 to 1 or higher. I have no idea what pistons are in the motor, it was a stock rebuild when I bought the car. Just trying to get an idea of cost from the machine shop.
 
Surface to volume ratio is: .0048in to 1 cc; for every .010 mill off the chamber side, cut .0095 off the intake side. A 10cc reduction of the chamber is approx one point of compression.

Good luck.
 
You can also tune TDC volume by head gasket. Here are the most common ones.
Mr Gasket 1121 .028 nominal thickness 6.5 cc
Fel Pro 1008 .039 thick 8.9cc
Fel Pro 8553 .053 nominal thickness 12cc
 
JFYI the style of valve used in the heads also makes a difference in the chamber cc's. Found that out yrs. ago when I installed a set of REV stainless valves in an old set of X heads I had. Dropped the chambers from 71 cc's to 66 cc's
 
If its open chamber, could also shave enough to make them closed chamber, raise compression and better chance of being able to run lower octane with the higher compression
 
fishy68 said:
JFYI the style of valve used in the heads also makes a difference in the chamber cc's. Found that out yrs. ago when I installed a set of REV stainless valves in an old set of X heads I had. Dropped the chambers from 71 cc's to 66 cc's
Click to expand...

Wow-that much difference? I assume REV valves are flat faced and they were proud of the seat a good bit...
 
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