LS6 heads on a 2004 6.0
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LS6 heads on a 2004 6.0 I'm looking to build a spare LS engine for my 98 Wrangler. Currently the Wrangler has a stock LS6/4L60E. Runs good but a local salvage yard is being cleaned out and I think I can get a clean 100K 6.0 core for $300. The plan would be to bore it for new forged pistons. Forged rods. New bearings all around. Then use the LS6 heads off my LS6 when needed.
So my question is what would the compression ratio be with the LS6 heads on the 6.0?
So my question is what would the compression ratio be with the LS6 heads on the 6.0?
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I was only thinking flat tops pistons.
Bore wise I hoping maybe 10 over and maybe up to 30 over.
Not looking for big HP numbers but an engine that will typically run on 91 octane and in a pinch 87 octane.
So since it's a bit of bench racing now and I know it would cost a bit more how about an iron block 5.3 bored and stroked to 383 cubes and then adding the LS6 heads?
Bore wise I hoping maybe 10 over and maybe up to 30 over.
Not looking for big HP numbers but an engine that will typically run on 91 octane and in a pinch 87 octane.
So since it's a bit of bench racing now and I know it would cost a bit more how about an iron block 5.3 bored and stroked to 383 cubes and then adding the LS6 heads?
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I was only thinking flat tops pistons.
Bore wise I hoping maybe 10 over and maybe up to 30 over.
Not looking for big HP numbers but an engine that will typically run on 91 octane and in a pinch 87 octane.
So since it's a bit of bench racing now and I know it would cost a bit more how about an iron block 5.3 bored and stroked to 383 cubes and then adding the LS6 heads?
Bore wise I hoping maybe 10 over and maybe up to 30 over.
Not looking for big HP numbers but an engine that will typically run on 91 octane and in a pinch 87 octane.
So since it's a bit of bench racing now and I know it would cost a bit more how about an iron block 5.3 bored and stroked to 383 cubes and then adding the LS6 heads?
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There are 2 real common 6.0 motors; LQ4 & LQ9. LQ4 comes with dished pistons, LQ9 with flat tops.
The LS2 is basically an aluminum LQ9 with 243/799 heads and the addition of AFM. Its compression is essentially the same as what you'd end up with in your combo. It's just under 11:1 from the factory so that's what you should expect. If you put those heads on a LQ4 you'll end up with something mid 10s, maybe 10.5 or so.
Frankly, sounds to me like if you got a "clean 100K 6.0 core", you'd be many many $$$$$ ahead to just leave the short block alone. Most likely doesn't need bearings, boring, and all that. Maybe change out the oil pump and timing chain as part of a cam swap. For $300 I'd think it's more likely the LQ4, butt who knows.
The LS2 is basically an aluminum LQ9 with 243/799 heads and the addition of AFM. Its compression is essentially the same as what you'd end up with in your combo. It's just under 11:1 from the factory so that's what you should expect. If you put those heads on a LQ4 you'll end up with something mid 10s, maybe 10.5 or so.
Frankly, sounds to me like if you got a "clean 100K 6.0 core", you'd be many many $$$$$ ahead to just leave the short block alone. Most likely doesn't need bearings, boring, and all that. Maybe change out the oil pump and timing chain as part of a cam swap. For $300 I'd think it's more likely the LQ4, butt who knows.
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But if the 6.0 is a GENIV (LY6, L76, etc.) then it may have AFM, VVT or both. And the knock senors have to be relocated to be compatible with the LS6 wire harness, and the reluctor wheel has to be changed from 58X to 24X.
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Since my Wrangler has a 2002 LS6 with a 24 tooth crank reluctor I would want to use a 6.0 with a 24 tooth crank reluctor.
Yes if the 6.0 didn't need boring that would fantastic. But because I'm paranoid (since the whole world is out to get me) LOL I will pull the engine apart to check all clearances.
The LS6 in my Wrangler runs great. No issues but a somewhat low mileage 6.0 would be hard to pass up.
Thanks for all the suggestions.
Yes if the 6.0 didn't need boring that would fantastic. But because I'm paranoid (since the whole world is out to get me) LOL I will pull the engine apart to check all clearances.
The LS6 in my Wrangler runs great. No issues but a somewhat low mileage 6.0 would be hard to pass up.
Thanks for all the suggestions.
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Just do a engine compression check on all the cylinders. If they check out good leave it. No need to tear a perfectly good motor apart. Even the Aluminum block engines will go 200k+ miles with very little wear.
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Haven't bought the 6.0 yet. Sounds like the new salvage yard owners want to sell the engines (all types) on the shelf as one big lot. Don't want to sell single items. I will keep talking to them.