Pistons

You may want to decompress that engine to 8:1 so you can run regular gas. Food for thought. At 10:1 or higher you will need 100 octane or 92 and an expensive fuel additive to prevent spark knock and piston damage.

The pistons have a notch in the tops and the original pistons had that notch pointing foreward on both banks meaning the left and right side were installed 180 degrees different.

I have a set of flat top that says it doesn't matter but Ford thought it did with the the standard 430 pistons.

On page 1-59 of the 1959 Thunderbird Shop Manual for the 430 at FIG. 26 it says Piston and Connecting Rod Assembly it shows pistons that are NOT flat top and "identification to the front of the engine" and in BOLD BLACK PRINT it says "Piston's are not interchangable from one cylinder bank to another."

The pistons shown are 10:1 with a raised top upward toward the intake manifold side. The set of flat tops I bought for an overhaul are marked it doesn't matter. Perhaps because the raised portion of the high compression standard 430 pistons would hit the head in turned the wrong way. With flat tops it shouldn't matter.

Are you the fellow that emailed me a day ago about rods and pistons? If so do you still need them?

Thanks,

Dave
aka
J-Bird430