Hi, could someone tell me my C/R, World Prod heads Windsor Sr 58cc chambers, Sealed Power pistons .30 p/n 12249N, apart from the part number, cannot find any info on the pistons, 73 Mexican block, anything else you need to know, Thanks, Alan.

 

Anywhere from 8.75 to 9.7 to 1 depending on the deck clearance. Closer to the deck the piston top is, the more compression you'll have. This info is only good for flat top 302 pistons with 4 valve reliefs.

 

The pistons fitted are domed, does anybody know the deck height to a mexican block!

 

The only sure way to figure deck height is to assemble the motor with one rod & piston, then measure from TDC. Then add all the part's dimensions.

 

Thanks for the reply, my motor is built, obviously to late to check measurements. regards Alan.

 

I found your pistons in the book: Ford Performance by Pat Ganahl . That's the old TRW forged pop up. Compression with 53 cc heads is 12.5 to 1, 10.5 to 1 with 64 cc heads, and 9.5 to 1 with 70 cc heads.

 

Thanks for all your help, regards Alan.