51751 pistons (93-97 EFI)

I have been looking for a while and can't find any info on these pistons, they are more compression height, smaller dish, and should yield approx. 1 number higher compression ratio, will they work as far as valve reliefs with d3 or d0ve heads, if so that would make a good build. Reason is there are a few of these engines lying around, I would install the other carb type heads and have a pretty healthy build. Just curious.

The pistons you speak of have enough valve relief (radially) that you can use about 2.125" of intake valve with out problems. We use the 5074 Ferrea for budget oriented iron heads both large and small chamber. At 2.11" it works well. Randy Malik passed on this tip to me some years ago.  

These pistons are hypereutectic and very heavy with bob weights in the 2570+ range. Keep RPM reasonable so the piston does not break at the pin boss.

Ford used a version of this hyper piston in its crate 460 engines back in the day with A-429 heads. A larger diameter valve notch was machined.
I have several examples of this piston with the bottom half missing.  



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