Changing pistons. What machining work should i have done?
#1
Changing pistons. What machining work should i have done?
I have a SDPC LS2 402 stroker that I'm swapping pistons on. The motor has around 5, miles on it now. My question is, what items should i have a machine shop clean up while I have everything apart. I imagine SDPC did a decent amount of machining when they did the rod clearancing and what not. At the moment, I'm just trying to figure out what would be routine machining, vs what would be little to no gain for the cost. I'll also be having the heads cleaned up while it's all apart.
Thanks
Thanks
#5
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COMP - FAST - PACESETTER - DIAMOND RACING - EAGLE SPECIALTY PRODUCTS - CALLIES - COMETIC GASKETS
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#7
I had to make a decision on lowering the compression ratio. I talked to Diamond Pistons about the piston that SDPC put in the 402's and they say its a great street/strip piston good up to ~700hp, but they wouldn't really recommend it if I was shooting way beyond that. And I really liked the ETP 245's I have on the motor now, and didn't really want to sell them unless I had to. So swapping in a good quality boost piston was the best choice for me. They'll have to be a custom piston though, as off-the-shelf ones seem to go from -15 to -28cc. I'd like to build it so I can run really low boost on 91 octane (if no e85 pumps are in range) or run e85 with the boost turned up and I don't think I'd really want to go under ~9.5:1 compression (still gotta find ideal compression range for e85). Unless I upgrade to an aftermarket PCM, 15psi would be my programming limit.
Thanks Matt, I was definately going to have the new assembly re-balanced, but it's good that's thrown in for anyone else reading this.
Thanks Matt, I was definately going to have the new assembly re-balanced, but it's good that's thrown in for anyone else reading this.