best 5.3??
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From: coatseville pa
best 5.3?? What is the best 5.3 to use with 800~900 HP in mind? I'm going all forged for reliability. Twin Turbo, not sure what turbos to yet,I don't understand all the numbers ye
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From: Cincinnati OH
The better 5.3s are the late 04 and up with ls2 rods. If your forging the engine then having the good gm rods is a non concern for you so any 5.3 would work fine.
I would probably use an iron block over an l33 alum block though.
I would probably use an iron block over an l33 alum block though.
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Joined: Dec 2011
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From: STL
With all forged internals, is there really any difference? If that's the route you're going you just have to decide if you want the aluminum or iron block. With forged internals, the aluminum block is plenty strong and weighs somewhere around 80 lbs. less. The aluminum 5.3s are harder to come by, though, and you pay a lot more for them when you do find them. I would say just get the iron block ($3-400 at a junkyard), rip out the guts, get the forged assembly in, and shed some weight elsewhere.
The "L33" coded 5.3s are aluminum blocks and have nicer 799 casting heads. These are twice as expensive as any other 5.3 on average. The cheap 5.3's that you're going to find ($200-400) are most likely going to be iron block engines. There are other differences but because you're forging it really doesn't make a difference. Go L33 if you want to save some weight though - the block will handle PLENTY of power.
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Verdad Gallardo TECH Regular
Joined: Dec 2011
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From: STL
You should look for IRON or...ALUMINUM. If you can't tell the difference between the two, you're gonna' struggle throughout this entire process. The 799 heads from the aluminum 5.3 would be nice, but that also might be too much compression for FI. IIRC, those yield somewhere around 10.9:1 or 11:1.
You should look for IRON or...ALUMINUM. If you can't tell the difference between the two, you're gonna' struggle throughout this entire process. The 799 heads from the aluminum 5.3 would be nice, but that also might be too much compression for FI. IIRC, those yield somewhere around 10.9:1 or 11:1.
What are the big differences betwen a LH6(Gen IV) and L33(Gen III).?. I know they are both aluminum blocks with flat top pistons, different reluctor rings 58t/24t(you need to use the Lingenfelter computer adapter), and the LH6 had the DOD set-up, but is there anything else greatly different from one to the other? Once you switch the lifters and oil pump out it should be pretty much the same as the L33 right?
Last edited by Packy; Aug 26, 2012 at 03:29 PM.
