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I guess the one good thing about them is everything balanced easily since these are close to stock weight with the Scat rods.
On the plus side, he can probably change the valves with the pistons at TDC.
It should peak somewhere around 5600 rpms. I wanted to go with a lighter forged piston and some better heads, but the budget just wasn’t there on this build
Maybe, as a general rule. but there are exceptions such as my friends 1200hp 354 chry. Previous pistons were 40++ grams heavier and used D017, 1/16, 3/16 ring pack. Emptied the puke tank every pass. New pistons are 1.2, 1.5 and 3mm, gas ported and dry as a popcorn fart. Great strides in rings in the last decade. Of course, there are racers who can break an anvil in a sandbox so it would be better to make their parts with more strength.
Lighter piston weight wasn't the goal here but when it was sufficiently thick and a shorter pin was used it ended up lighter. Finish line rpm is 9600 which is way more than expected. Dykes type rings are just a crutch IMO and their very design promotes ring flutter which causes the 2nd ring to not properly control oil. Ring seal is paramount and everything after that is achieved becomes easier. I don't think throwing more weight than necessary is desirable--A piston is a very good fuse and sometimes a hole blown through a piston has saved an engine from complete destruction.ptuomov wrote: ↑Mon Dec 23, 2019 7:23 pm Was that because the rpm exceeded the ring flutter critical rpm for the combination?
I’m just rambling here, but for these latest engines (two short blocks), we started with the max rpm and fuel and then the ring width and piston weight followed from that. Once you add the boost, the math ended up requiring piston oil squirters. Then the bearings came from that, as well as the constraint of using the stock crankshaft.
The point being is that heavy piston isn’t necessarily a negative unless if it’s too heavy for the stroke and the rpm.
