B'klyn9C1

I've been looking around the web and all of the LSx builds for a 4.00" and 4.100" stroke all call for a 6.125" connecting rod. Why not a 6.200" con rod ?? Are they afraid that the piston used will be too short and not durable??

I did see that Lough Engine Service of Oak Ridge, Missouri and CC Performance Parts of St. Helens, OR does sell 416 ci and 427 ci LS3 stroker builds with the 6.200" rods, but nowhere else that I have seen.

Is it true that the LS3/L92 block has sleeves long enough to accomodate the 4.100" stroker crank without poking the pistons out of zeroed deck where the LQ9/LQ4 block is does not???. So can I build a 427 ci shortblock that can be used for a daily driver with occasional road race and autocross use if use the LS3/L92 block instead of the LQ9/LQ4 iron block??? Can it be as durable as the using the iron block?? Let's say a good 100,000 mile motor?

jsds500

iTrader: (1)

Maybe it has something to do with oil ring getting to far into the pin bore?

AES Racing

iTrader: (6)

Its doable with a 4.000 crankshaft, 4.100 forget about it, would need a .990" CH piston, its a custom piston, would become an expensive project. Lot of potential issues with less then 1.000" compression height.

We just fixed an engine that cracked a couple pistons with .990" CH. The original builder didn't use the correct ring dimension and ring grove dimension for the application.

No, sleeve length is the same. The pistons come out the bottom of the bore regardless even with 4.000" crankshaft, just not as much. The skirt of the piston (from a knowledgeable piston mfg) will have the correct taper skirt for LS stroker.

Another reason why you don't see as many 6.200" rod setups, the rods do cost more, 99/100 people on here are looking for best price, most shops like us are buying rods in volume, 6.125" rods cost little less (due to popularity) and they work perfect for most applications.

96 Comp T/A

iTrader: (8)

I put 6.300's SBC Eagle rods (with the pin end offset unfortunately) in my stock stroke (eagle crank) motor with off the shelf 4.0" stroke pistons from Diamond. If I could do it all over again, I would have just bought the 4" crank and the 6.125 rods. I purchased the rods and pistons when I had a stock crank. Come to find out one of the journals was wiped. Since I already had the rods, I bought a stock stroke eagle to replace it. It runs great, but the extra 40 or so cubes would have been nice.

briancb1

That short of a CH would put the oil ring deep into the pin. Not to metion the stability it's just not a practical idea for the street and would buy you nothing.