I may have found an LS1 shortblock I can drop in my truck but I want to know if I can use the 862 heads from my 4.8 on the LS1. Also, what will the CR be if I use the 862's on the LS1. Thanks in advance
I may have found an LS1 shortblock I can drop in my truck but I want to know if I can use the 862 heads from my 4.8 on the LS1. Also, what will the CR be if I use the 862's on the LS1. Thanks in advance
~ Forged engine of some type ~ Ball bearing turbo of an unconfirmed size ~ 4L8000 trans ~ Beefy fuel system ~
It will bump your CR up a hair, 4.8/5.3 heads and LS1 heads flow the same, the only difference is the combustion chamber.
2006 SilveradoLittle Black Bitch
So about what is my CR with 862's on a 4.8L and what will my CR be with 862's on an LS1 ?
~ Forged engine of some type ~ Ball bearing turbo of an unconfirmed size ~ 4L8000 trans ~ Beefy fuel system ~
it's a pretty common mod with ls1 guys to raise compression. I'm not sure the exact numbers, but you may want to lower the boost a psi or 2.
blown transmissions are about as useful as 97% of the guys on this forum
Looks like 66cc combustion chamber volume. Should put ya around 10.5:1 I think.
Not the best choice for a boosted application I wouldnt think. Too much static compression. I would think you would be better off with some heads off of a 6.0 umm 317s i think, they are supposed to slow as well as 243 heads and are cheaper? You could probably sell your 862s and break even. You will have a hell of a time avoiding pre ignition with pump gas with those heads and any kind of boost at all.
99 silverado 2500 4x4 ec lb, lq4 with 243 heads, pace setter long tubes, true duals with x pipe and bullet mufflers, comp 222 224 112 cam, 8.1 truck injectors, 4l80e with 2800 stall, 373 gears, 285 75 16 tires, efi live tune in progress, 350rwhp 360tq, 11.8 average mpg mixed driving
Ok there are 3 sets of 317s on performance trucks classifieds right now. One set is less then $200! If your gonna run boost go get em!
99 silverado 2500 4x4 ec lb, lq4 with 243 heads, pace setter long tubes, true duals with x pipe and bullet mufflers, comp 222 224 112 cam, 8.1 truck injectors, 4l80e with 2800 stall, 373 gears, 285 75 16 tires, efi live tune in progress, 350rwhp 360tq, 11.8 average mpg mixed driving
+1 truck heads would boost your compression too muchOriginally Posted by aj06bolt12r
http://ls1tech.com/forums/ls1-domest.../t-111207.html
the truck heads are 63 cc and the 317 heads are 72cc
2008 GMC Sierra SLE....370ci LY6 with some goodiesSOLD
1995 C2500- LS1 swap with a mp112
build thread- http://www.ls1truck.com/forums/lsx-t...-ls1-swap.html
Unless you slapped some dished forged pistons in it. That way you gain some strength and you can keep your heads.
So an LS1 with 317's would put my CR around 10:1 ? If so, then I think that would be optimum for about 12 psi of boost.
~ Forged engine of some type ~ Ball bearing turbo of an unconfirmed size ~ 4L8000 trans ~ Beefy fuel system ~
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