i need a some help and advice
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From: west burbs of chi town
i need a some help and advice well where do i start i'm redoing an ls1 block line honed and magnafluxed......i have a set of 6.1 rods on the way and a stock stroke crank....... 
here is where i am confused......
i have stage 2 heads that are milled 35 thousands and have had the bowls polished and gasket matched......
now where do i start i am not sure what pistons to order as far as CR and how all that works i know that if i plan on boosting/spraying the i need low CR pistons but my concern is will a low CR piston produce a decent N/A amount of horsepower......
i was putting down around 400 to 410 at the wheels and the cam i had was nice 236/232 @.050 witha 578/571 lift on a 112 lsa.....i liked it very much but the exhaust relief is'nt enough for either so i wanna go bigger......
what would anyone recomend as far as if say i wanna boost/spray the car but someday decide not to will the low CR pistons hurt me as far as N/A is concerned and how bad rwhp wise and if so does anyone have a recomendation as to what cam i should use that will be good for N/A or power adder in the event that i change my mind one way or the other......
also with the heads being milled that much what are the dangers and how big of a cam can i go along with it........
the heads have 7.4 push rods and will have 1.7 (i think that was the stock ratio) shafted rockers i just want to make sure i do this right the first time and get the most bang for my buck N/A or power adder thanks in advance for all the help you guys...........
here is where i am confused......
i have stage 2 heads that are milled 35 thousands and have had the bowls polished and gasket matched......
now where do i start i am not sure what pistons to order as far as CR and how all that works i know that if i plan on boosting/spraying the i need low CR pistons but my concern is will a low CR piston produce a decent N/A amount of horsepower......
i was putting down around 400 to 410 at the wheels and the cam i had was nice 236/232 @.050 witha 578/571 lift on a 112 lsa.....i liked it very much but the exhaust relief is'nt enough for either so i wanna go bigger......
what would anyone recomend as far as if say i wanna boost/spray the car but someday decide not to will the low CR pistons hurt me as far as N/A is concerned and how bad rwhp wise and if so does anyone have a recomendation as to what cam i should use that will be good for N/A or power adder in the event that i change my mind one way or the other......
also with the heads being milled that much what are the dangers and how big of a cam can i go along with it........
the heads have 7.4 push rods and will have 1.7 (i think that was the stock ratio) shafted rockers i just want to make sure i do this right the first time and get the most bang for my buck N/A or power adder thanks in advance for all the help you guys...........
You need to decide what you want to do, Boost or Spray. They are two differant animals. Boost low compression spray high compression. With the milled heads you are allready moving tword the spray side. If you want to go boost you probly going to have to get differant heads. To what cc's have your heads been milled to? What size bore is your block going to be?
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On The Tree
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From: west burbs of chi town
it will be a honed out 346 so what is that like a 348 ar something..i was always under the impression that if ya sprayed it boosted the car ya wanted lower cr for both but you can or want a higher cr with nitrous ans as for the heads i don't know i would have to look at the casting numbers and find out plus i could always use a thicker head gasket if i needed i suppose what ya think
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From: BFE
Dished forged pistons for boost target 9.0:1 SCR
Forged pistons with valve reliefs for N2O, run a tight quench (.030> .035) using thin Cometic gasket and at least 11.0:1 SCR. The valve reliefs will allow a bigger cam.
In either case I would use the lightest forged rods you can afford.
Forged pistons with valve reliefs for N2O, run a tight quench (.030> .035) using thin Cometic gasket and at least 11.0:1 SCR. The valve reliefs will allow a bigger cam.
In either case I would use the lightest forged rods you can afford.
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From: west burbs of chi town
i have a set of ams racing forged on the way right now the casting numbers on my heads are 241's so i'm gonna go look at the thread that has the listing for cr and figure out closely to what it would be with the .035 mill job also might have to deck the block which means it will be a total of .045 off any suggestions on what size cam and gasket also what is a good nitrous piston that won't cost me an arm and a leg but not cheap either not gonna run a 500 shot but maybe 250 or so one that will hold up nice like
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From: BFE
Wisceco with 2cc valve reliefs are good, then there is Diamonds.
First get the shortblock together. After that, proceed with choosing your gasket depending on your piston to deck position and mill your heads for desired SCR.
Numbers on paper mean jack, they never match the built up.
As for cam, get a cam for NA application that will accept your desire to shoot 250 shot.(FM9>FM11>FM13>G5x2>TSP233/239 etc...)
Better get head studs also to keep those heads bolted down. 250 is not a small shot.
First get the shortblock together. After that, proceed with choosing your gasket depending on your piston to deck position and mill your heads for desired SCR.
Numbers on paper mean jack, they never match the built up.
As for cam, get a cam for NA application that will accept your desire to shoot 250 shot.(FM9>FM11>FM13>G5x2>TSP233/239 etc...)
Better get head studs also to keep those heads bolted down. 250 is not a small shot.
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On The Tree
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From: west burbs of chi town
studs ae backordered right now last i heard but fm i'm assuming you futral motorsports correct i'll have to check that out......can someone answer me another question when using arp bolts for the bottom end because the torq specs are more psi do you have to line hone the block due to the fact that you will squish the bearings
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On The Tree
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From: west burbs of chi town
yep i think it will go to the shop and let them machine what they need to and go from there figure out what i want to do and what not thanks for the help