Combustion Chamber size and Compression Ratio of The Twin Vortex Head

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There have been a number of questions about the CR and valve clearance for those that have put in 7X or larger valves.  Here is some comments from Rudy Bennett.  At this point the head thickness will be 2 inches, which will give you the results below.  We may decide to add a small amount to this and allow users to mill it down, but no final decision has been made.  Remember a thicker head gasket is also an option if you want a smaller CR.



From Rudy Bennett one of the designers of the original Twin Vortex Head.

The New Aluminum Cylinder  Chamber  is the same as a new 232 -80,cc cyl Hudson  Head. and below is a picture of stock  In and Ex valves in the new chamber.  Depending on the size of the Valve Head will determine that, but any modifying (maching )  of the inside Chamber will have an effect on the CC  and the Compression Ratio of the head.  ( one of my Hudson friends  Had machined the sides of the chambers because of the over size IN valve Heads but lowered the CC of the chambers 

Stock bore and stroke on a 308 eng would be 8.4  C.R.

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Please note that Rudy Bennet contacted me to correct the source of the information  It came from Chuck Fellows, not Rudy.