This is a "tip" for anyone considering aftermarket pistons for your nailhead. Having just finished the first unit and moving on to the next one, we've learned much about ordering "custom" pistons. We used set of Ross with their dome configuration and our "design" from the rings down (pin size, C.H., ring config., internal milling, etc.). The only issue we had was with the fact they used symmetrical valve notches, which turned out to be a slight drawback. Their location is somewhat "off" from where they're needed, most notably the exhaust. They had to be relocated by flycutting, which now gave us a
"double" notch and changed our C.R. figure slightly. This unit was based on the 401" block and "upstroked" to a 426" with the stock crank, Howards rods, and the Ross pistons. The next one will incorpoprate the 425" block and yield a 450" unit. In the future we would ask them for NO VALVE NOTCHES at all, and we'll machine them as required. We do plan to give the feedback to Ross. Using a "Schneider" cam with .520" lift and adjustable rockers, we had to flycut the exhaust notches (.050") for add'l clearance, the intakes were ok. Thanks, Gary in N.Y.
P.S. It's my understanding that all the aftermarket piston mfr's. use the same "dome/valve notch" layout, so it really doesn't matter who makes them. This is the first N.H. we've built on this platform. We've done a number of "stockers" over the years, but none to this extent. We had to remove 300+ grams from the crank for balancing, should be a "quick-revver" with the "Hilborn" on top.
"double" notch and changed our C.R. figure slightly. This unit was based on the 401" block and "upstroked" to a 426" with the stock crank, Howards rods, and the Ross pistons. The next one will incorpoprate the 425" block and yield a 450" unit. In the future we would ask them for NO VALVE NOTCHES at all, and we'll machine them as required. We do plan to give the feedback to Ross. Using a "Schneider" cam with .520" lift and adjustable rockers, we had to flycut the exhaust notches (.050") for add'l clearance, the intakes were ok. Thanks, Gary in N.Y.
P.S. It's my understanding that all the aftermarket piston mfr's. use the same "dome/valve notch" layout, so it really doesn't matter who makes them. This is the first N.H. we've built on this platform. We've done a number of "stockers" over the years, but none to this extent. We had to remove 300+ grams from the crank for balancing, should be a "quick-revver" with the "Hilborn" on top.