5.3l engine build!!

Hey Guys, i got a lm7 5.3 today and been planing my build, as you can see the truck has 220,000 miles on her and planing to push her to 300k but im ready to get my build going, i just have some things jotted down, would love to here ya's opinion and what has been most productive..
so far i got
Lm7 5.3l block
have honed,bored,decked and cleaned up, new cam bearings..
bore out 0.12
pistion bore will be a 390 instead of a 378
stroke will remain stock at 3.622 unless someone says i should do somthing else
Rods out of a ls1
Stock Crank- new bearings
Stocks head with 3 angle valve job port and polished and all that good stuff
Trick Flow TrackMax .575 220/224 0.50 cam
still have to look into springs, lifters and push rods and all that good stuff.
does anyone know where a good build is on her?
like what there specs where.
im not gonna boost most likely so what should i do about commpression,,
would love to here all opionions EXCEPT for buy a 6.0l. i've determinded to just stick with the 5.3l
Thanks

Good compression ratio for 93 octane would be about 10.5:1, give or take a little.

since your boring it out and use ls1 rods, bore it to ls1 specs and use ls1 pistons as well

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Originally Posted by beingblueeyes

since your boring it out and use ls1 rods, bore it to ls1 specs and use ls1 pistons as well

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+1 for sure

no replacement for displacement

Yea. I for got to add I was using ls1 pistons. So looks pretty good for a dd? I plan on runnin 93 since I already do now.

What heads are you planning on running?

Stock heads with some port and polish 3 angle valve job. As far as numbers I think there 8 something or 243

Most likely if its an LM7 they are 862's.

If youre wanting to up the compression definitely mill them also and toss in flat top pistons.

newb question... Why wouldnt you go ahead and bore it out to 4 inches and use lq9 or ls2 pistons?

not enough material in the cylinder walls to safely take it out to that diameter. A lot of 5.3s can't even take the LS1 bore without being weakened.

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Originally Posted by RedHeartbeat

not enough material in the cylinder walls to safely take it out to that diameter. A lot of 5.3s can't even take the LS1 bore without being weakened.

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What 5.3 can be safety bore out to 3.905 ?

be sure any shop you take it to for boring checks it before they bore it. Some blocks have core shift and will have a ton of material on one side of the bore and little on the other. I believe they use a sonic tester to check the wall thickness.

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Originally Posted by RedHeartbeat

not enough material in the cylinder walls to safely take it out to that diameter. A lot of 5.3s can't even take the LS1 bore without being weakened.

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Oh okay, i gotcha. Makes since of course, just figured all the ls motors had the same cylinders just the smaller bore ones had more thickness. Learn something new everyday.

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Originally Posted by DSCZ71

Oh okay, i gotcha. Makes since of course, just figured all the ls motors had the same cylinders just the smaller bore ones had more thickness. Learn something new everyday.

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Anything up to a 5.7 do. The 6.0, 6.2, and 7.0 are all different.

Now I'm starting to second guess. This project. So do you think I should still bore? I'm want something to last along time. Now I'm thinkin about a 6.0l. That was my goal to begin with. Just 5.3s are easier to find.

Get a 6L and call it good. Machine work, parts and gaskets would add up go more than the price diff of a 6L vs 5.3

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Originally Posted by RedHeartbeat

Get a 6L and call it good. Machine work, parts and gaskets would add up go more than the price diff of a 6L vs 5.3

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Good point. You can find an lq4 or even lq9 pretty easily and for not too much more than a 5.3. From the little researching i have done i would say you could get a 5.3 for $500-750 all day long and a lq4 or lq9 for around $1000. An lq4 can be had for under $1000 and lq9s are usually a little over $1000. Check out car-part.com

Btw, what happened to the procharged 5.3 in your sig?

she still running with 230k on her, no smoking or anything im very impressed with these motors. i know she ll be pushing 300k no problem, i drive it everyday to work, im not taking the motor out till she goes but i just would like a build to do and have one sitting on the shelf all ready to go, i've seen a couple 5.3's and 6.0's running 367k and still running strong,

Sweet, sounds good! Yeah, these suckers just dont quit! Any reason why you wouldnt go FI on the next motor? I mean why not build a badder motor than you got now (like you are talking about doing) and then put the procharger on it once you swap it in?

well, i might, i kinda wanna do a rear mount twin sts turbos. but i have a little girl on the way and im 21 years old. just trying to stay afloat. i just opened my own performance shop with the money my dad left behind so money is tight right now. so far the shop is doing well i have a 6.0 build im doing for a cust right now 80k project so. mine should be sometime soon,. i wanna run 10's with my daily driver.