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I have a rebuilt LQ4 with stock LS3 heads and want to add more power. I have 1500 miles on this set up in my Silverado and have motor tore out for cleaning.
The motor as it sits now
Forged Hbeams
LS3 heads
Mahle L92/Ls3 Power pak pistons
L92 Truck intake (ported)
102 MM TB
222/230 112+3 (.630/.608)
3600 Stall
CR=10.28:1
I have been reading on getting the heads milled and using a thinner head gasket to boost up my compression ratio as it seems the LS3 heads like higher CR. I would also like to get a new cam and have a line on a 228/230 for cheap but don't if thats the right way to go for a truck.
From what I read these heads really like 11.2-11.4 CR and allows for good timing and seems I can get close if I get a .04o gasket and get these heads down to 64 CC. (have no clue if that's even possible)
Any Help you guys have would be great, I was also thinking a 408 kit but to be honest don't know if I have the funds to make that happen.
Anyone? Is that a good target CR ratio of 11.2 for these heads?
I was looking up cosmetic gaskets and cost for head gaskets at .040 is almost $200. Can I get the block milled lets say.010 and use a stock GM gasket to get my self to same height? Piston is already out the hole .01 so no clue if you can even deck it that much.
There's no magical compression ration for heads, as heads themselves are not the ones that "like a certain compression". It's the overall combo and what cam you have and how much timing you can run with your gas of choice.
Up to 11.5 is plenty safe on the street and will definitely get some power. Also that 228/230 cam is not going to work well with stock LS3 heads so don't bother.
There's no magical compression ration for heads, as heads themselves are not the ones that "like a certain compression". It's the overall combo and what cam you have and how much timing you can run with your gas of choice.
Up to 11.5 is plenty safe on the street and will definitely get some power. Also that 228/230 cam is not going to work well with stock LS3 heads so don't bother.
So I just need to get a cam that works best with that CR. Everyone I call has different ideas of what cam to use and that's where Im getting lost. I want the biggest/Most power for a DD that will move this truck with the 3600 Stall. Im going to make some calls today and get some ideas of cams spec's.
09-07-2014, 09:46 PM
Need to upgrade for more POWER! 
