L33 build
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Teching In
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L33 build First ls swap is about to to take place and I’m trying to get my ducks in a row. I purchased an l33 with 120k off eBay. 900$ was what I was looking to spend and that’s what I got it for. Anyway I’m sending heads and block to machine shop to get bearings changed and heads smoothed not so much milled but he said they will take something off. I’m putting in speed pro std sized pistons and moly rings, but I keep hearing about thinner head gaskets to boost compression. I asked summit what’s thinnest they offer and the rep said they only have 1 for my engine and it’s the same thickness as factory. What brand, part number or type are you guys using?
Not stating what goals in mind so hard to help best to mill heads and use standard head gaskets but .045 from Cometic will work great you just order straight from them will get them in a week.
I will say mill heads .030 thous to increase compression by about a half a poit if want some extra muscle.
Compression Ratio is 9.49:1 or 9.9:1 on around 2005 year models low for performance if that's what your seeking.
I will say mill heads .030 thous to increase compression by about a half a poit if want some extra muscle.
Compression Ratio is 9.49:1 or 9.9:1 on around 2005 year models low for performance if that's what your seeking.
L33 uses flat top pistons and is roughly 9.9ish. Why increase the cr?
Dont run a thinner gasket. Just run it as is.
You want more cr bore it out. L33 5.3 alum blocks can handle an ls1 bore even fwiw.
Dont run a thinner gasket. Just run it as is.
You want more cr bore it out. L33 5.3 alum blocks can handle an ls1 bore even fwiw.
Last edited by tech@WS6store; Oct 29, 2017 at 06:43 PM.
First ls swap is about to to take place and I’m trying to get my ducks in a row. I purchased an l33 with 120k off eBay. 900$ was what I was looking to spend and that’s what I got it for. Anyway I’m sending heads and block to machine shop to get bearings changed and heads smoothed not so much milled but he said they will take something off. I’m putting in speed pro std sized pistons and moly rings, but I keep hearing about thinner head gaskets to boost compression. I asked summit what’s thinnest they offer and the rep said they only have 1 for my engine and it’s the same thickness as factory. What brand, part number or type are you guys using?
Depending on how much piston protrusion,and piston rock you have will dictate how thin you can go on the gasket. You may be able to go to a cometic .040 but it won't gain you much compression.
If you want to yield a higher CR with what you have, you can also mill the heads.
We would need to know How much the piston is out of the hole to give an exact number,
But if you were .005 above deck, used an .040 gasket, and milled the heads to 61cc chamber you could achieve up to 10.88:1 CR
An L33 is roughly 9.9:1 compression. I don't know why your changing the pistons as they are a flat top from the factory.
Depending on how much piston protrusion,and piston rock you have will dictate how thin you can go on the gasket. You may be able to go to a cometic .040 but it won't gain you much compression.
If you want to yield a higher CR with what you have, you can also mill the heads.
We would need to know How much the piston is out of the hole to give an exact number,
But if you were .005 above deck, used an .040 gasket, and milled the heads to 61cc chamber you could achieve up to 10.88:1 CR
Depending on how much piston protrusion,and piston rock you have will dictate how thin you can go on the gasket. You may be able to go to a cometic .040 but it won't gain you much compression.
If you want to yield a higher CR with what you have, you can also mill the heads.
We would need to know How much the piston is out of the hole to give an exact number,
But if you were .005 above deck, used an .040 gasket, and milled the heads to 61cc chamber you could achieve up to 10.88:1 CR
Youll be at at least 10.5 by going to a 3.898 bore plus have the potential for more power already based off unshrouded valves and cubic inch alone.
Building pretty much an ls6 out of it. Add in piston above deck and youll be in the 10.6 to 10.7 range with stock thickness gasket.
Of you already have the pistons its a moot point obviously, but i am sure we could have saved you some money there and got you in on a better budget than summit and customized it for you.
Cometic gaskets are going to run at least $130-160 depending on whom you get them from which is nearly $100+ more than stock head gaskets.
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Teching In
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Going from .051 to .040 will gain about .3 to .5 depending on bore size used on the gasket also. With cometic you can run them pretty tight of you want.
Youll be at at least 10.5 by going to a 3.898 bore plus have the potential for more power already based off unshrouded valves and cubic inch alone.
Building pretty much an ls6 out of it. Add in piston above deck and youll be in the 10.6 to 10.7 range with stock thickness gasket.
Of you already have the pistons its a moot point obviously, but i am sure we could have saved you some money there and got you in on a better budget than summit and customized it for you.
Cometic gaskets are going to run at least $130-160 depending on whom you get them from which is nearly $100+ more than stock head gaskets.
Youll be at at least 10.5 by going to a 3.898 bore plus have the potential for more power already based off unshrouded valves and cubic inch alone.
Building pretty much an ls6 out of it. Add in piston above deck and youll be in the 10.6 to 10.7 range with stock thickness gasket.
Of you already have the pistons its a moot point obviously, but i am sure we could have saved you some money there and got you in on a better budget than summit and customized it for you.
Cometic gaskets are going to run at least $130-160 depending on whom you get them from which is nearly $100+ more than stock head gaskets.
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Thanks for the reply guys. I found them on cometic, but a wrench was thrown in now. Ls1 block for 400$. I planned on buying a set of pistons for the l33 anyway, and I know the truck crank and rods are stronger than the ls1. Using the l33 heads I might be able to make some good power over my l33. I’m not budget building anything, I have money for this project and would like the most bang for my buck.
Bang for the buck doesn't usually include N/A or any machine work when it comes to 5.3s, especially not one as capable as an L33. You would be better off just buying an LS1 or LS2 block if you want N/A power.
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Thread Starter
Teching In
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Bang for the buck with an L33 would be to throw on a nice big turbo on the stock long block. Those things are worth their weight in diamonds when it comes to budget big power builds. There are probably a dozen of us making 1000+ HP on stock L33 long blocks with a $1500 turbo setup.
Bang for the buck doesn't usually include N/A or any machine work when it comes to 5.3s, especially not one as capable as an L33. You would be better off just buying an LS1 or LS2 block if you want N/A power.
Bang for the buck doesn't usually include N/A or any machine work when it comes to 5.3s, especially not one as capable as an L33. You would be better off just buying an LS1 or LS2 block if you want N/A power.
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Teching In
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I saw that when I search third gen ls swap but does that expose the turbos to more elements and shorten the life span.
Im going to look at this ls1 block after work this evening, they seller has it posted on offer up and it’s been there for 2 months now, I’m going try to get everything he has for the price he’s asking for the block. My machinist told me not to mess with anything that spun a main but rods all day. How can I tell if it’s good or not? There has to be a reason other than “I got a new engine” to pull it out.
Im going to look at this ls1 block after work this evening, they seller has it posted on offer up and it’s been there for 2 months now, I’m going try to get everything he has for the price he’s asking for the block. My machinist told me not to mess with anything that spun a main but rods all day. How can I tell if it’s good or not? There has to be a reason other than “I got a new engine” to pull it out.