ckpitt55

iTrader: (4)

Looking to get some c&c on my component selection before I set this plan into motion.

I'm building for 11:0 SCR, 8.5:1 DCR, and 0.030-0.040" quench in mind. According to my calcs this combination of components gets me pretty close:

Stock crankshaft (may polish journals as necessary but they are really clean)
Diamond LS1 Street/Strip Flat Top Pistons - #11502, 3.905" bore
LS1 Scat 4340 H-Beam Connecting Rods - #6612521, 6.125" length
241 ported heads milled for 62 cc chambers (~0.040")
0.045" gaskets, 0.034" quench
TSP 228R cam

The pistons have a -2cc dish so I'm not worried about PTV issues with milling the heads, though that will definitely be double checked. Block will be torque plate honed for minimum clearance spec on pistons, mains will be align honed as needed to compliment ARP main stud install. Entire rotating assembly will be balanced.

Hope to make 420ish with full length headers once it's all said and done. Will also have an LS6 intake and ported TB on it. Reasonable goal?

td1168

iTrader: (2)

I think you'll be right there or just a little higher with a good tune. Your combo looks real good. I used the arp main stud kit and didn't have to get the align hone done but I know this varies from one block to another. I had to have the rods resized when I installed the arp rod bolts.

garygnu

don't need main with studs ,which do require honing!

td1168

iTrader: (2)

No they don't always! I used a dial bore gauge and checked mine after retorquing the main caps. They were round. You need to get your info correct before putting it out here to others!

Fastdriver1992

iTrader: (1)

any reason your going with a SCAT rod? Diamond pistons are definitely one of the best out there, but usually people choose the Compstar rods to go with them... i've heard that SCAT rods are not the best.

LilJayV10

iTrader: (39)

This is going to go well.

ckpitt55

iTrader: (4)

If I didn't have to replace the pistons I'd likely be staying with the stock rods and resizing them, but since that isn't the case the stock rods severely limit my piston selection. Instead of putting money into machining the big end and bushing/honing the small end to fit a floating pin, I'd rather put it towards a set of forged rods.

Will look into the compstars - from what I've been able to find so far it seems that they maintain better tolerances / have a better finished product than the scat rods, no?

And it's been proven time and time again that ARP's do distort the bores of whatever they're going into, just depends on to what extent. I installed them in my rods - and I got o-o-R values that were twice the allowable spec. I installed the main studs and took measurements - right on the hairy edge and was limited by the resolution of my gauge (I'm using a nice mitutoyo 0.0001" gauge). When you're dealing with tolerances of this level, it's pretty dumb to just throw stuff together and call it good, especially with the money involved.

That being said, I'm going to have a brand new set of 134-6006 ARP 8740 Rod bolts for sale that have never been run. Bought them before I realized I needed new pistons, and since I'm buying new rods I won't be needing them. PM if you're interested, I can't list in classifieds yet.

ckpitt55

iTrader: (4)

Ended up pulling the trigger on the H-beam 4340 compstar rods with ARP 2000 7/16" bolts. 6.125" length for 2.100" journal, 618g, PN# CSC6125DS2A2AH. Maybe overkill for what I'm doing right now but I won't have to worry if I decide to throw some boost at it somewhere down the line.

RezinTexas

Your math looks right, I get just slightly less compression than your numbers (10.85 and 8.38) when assuming the volume above the piston top ring as part of the clearance volume. I also used the following additional assumptions:

head gasket bore = 3.950"
piston compression height = 1.315"
machining done to block deck = 0.000"
piston top ring land OD = 3.854"
piston top ring land depth = 0.250"
IVC = 68.5-deg ABDC

ckpitt55

iTrader: (4)

The only difference between your and my calcs was I used a 3.910" head gasket bore and at the time didn't account for the air volume above the top ring land. The difference in gasket bore really doesn't seem to make a big difference. Plugging your assumptions in I get 10.86/8.39, so I think we're on the same page. I guess I could always mill the heads a couple thou more to compensate.