BONES
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- May 5, 2021
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Ls3 or 383 stroker?
- Thread starter JM PRO
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Fullthrottleguy
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- May 5, 2021
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Without rehashing whats been said here are the ways I lay out the pro's and cons
If you are "regular" duner and just want good reliable power and will be happy with what you get . A crate 525HP ( which with headers and tune will be closer to 560) is a nice combo - the power band is nice for regular duning good bottom end and good midrange and if you regularly change the oil and keep the filter clean its a 10 season engine. I have done quite a few.
Its not great platform if you're sick of the power quick. Easiest LS Power mod is add a superchargers - even modest boost 10lbs is 125-130 More HP and more importantly 100-150Ft Tq,... However the crate LS3 is just a bad platform for boost they don't do well stock with boost over 9 lbs thery also have very cloise to 11:1 compression measured - if you are lucky you we not see too much blow by and power loss in a couple seasons you will get wrist pin noise and eventually failure
The other boost in TQ you can feel is to stroke the LS3 going to a 416 that will usually yield in honest not bench racing numbers ...75Ft TQ gain and 50HP - you will feel that assuming you change the cam and springs ,,, But thats a fairly large investment and every day prices go up on good parts
The LS3 has the shortest cylinder of all the LS engines and in general a 5 over bore is all you are getting relaibily, so stroking those with standard sleeves to a 416 in future will use oil and wear rings and pistons - you will have a couple good seasons then power will fall off' oil use will go up alot
The LS1 platform is an old block but it is good (LS6 is way better) but not as strong as the LS3 block itself but has longer cylinders - they do really well when you stroke them to 383 - they generally make more power than a stock LS3 in the mid range even though the heads (Cathedral) are not as good as the LS3 in most areas - with the "right" cam they out perform the LS3 heads up to 4500RPM
You will feel the TQ on a 383 over an LS3 and because you now have a forged bottom end it can take a lot more abuse (unless you use crappy Chinese components) and that means more RPM reliably and if you watch the compression you can supercharge for outstanding results
But its going to cost you more to do your 383 than buying a crate because as said you sell the 5.7 pretty easily if it runs well.
I build a fair amount of every combo LS and if I had a 5.7 that was not tired - I would drop and SC on it and that 125+HP and even stock 100 FT Lbs TQ would outperform the crate engine for less money at 9Lbs boost and way less headaches and its easy labor wise - but does require other mods and a tune depending on your ECM that can be cheap - hard or replace it
Since I do these all the time - I can say 100% whatever you think you are gonna spend on a crate or stroker job - add 50% - you will have pieces you will forget or want to upgrade -
In any case no matter how you go ....you will have to upgrade the fuel system and thats not cheap, you probably will want to replace thr radiator and fans - More HP=more heat and you will have problems you never had. More HP - bigger clutch and as others have said - drivetrain needs to be considered as well as tires and it goes on and on - Catch can, bigger Air filter (more CFM) Bigger throttle body (free hp kinda) Probably swap thr ECM for something more modern and better tuning. Headers on Any chose you make should be at least 1 7/8 most 5,7's are 1.5" or 1 5/8 all those pieces make or break a build power wise .. I could go on I fix these issues daily ...
If you are "regular" duner and just want good reliable power and will be happy with what you get . A crate 525HP ( which with headers and tune will be closer to 560) is a nice combo - the power band is nice for regular duning good bottom end and good midrange and if you regularly change the oil and keep the filter clean its a 10 season engine. I have done quite a few.
Its not great platform if you're sick of the power quick. Easiest LS Power mod is add a superchargers - even modest boost 10lbs is 125-130 More HP and more importantly 100-150Ft Tq,... However the crate LS3 is just a bad platform for boost they don't do well stock with boost over 9 lbs thery also have very cloise to 11:1 compression measured - if you are lucky you we not see too much blow by and power loss in a couple seasons you will get wrist pin noise and eventually failure
The other boost in TQ you can feel is to stroke the LS3 going to a 416 that will usually yield in honest not bench racing numbers ...75Ft TQ gain and 50HP - you will feel that assuming you change the cam and springs ,,, But thats a fairly large investment and every day prices go up on good parts
The LS3 has the shortest cylinder of all the LS engines and in general a 5 over bore is all you are getting relaibily, so stroking those with standard sleeves to a 416 in future will use oil and wear rings and pistons - you will have a couple good seasons then power will fall off' oil use will go up alot
The LS1 platform is an old block but it is good (LS6 is way better) but not as strong as the LS3 block itself but has longer cylinders - they do really well when you stroke them to 383 - they generally make more power than a stock LS3 in the mid range even though the heads (Cathedral) are not as good as the LS3 in most areas - with the "right" cam they out perform the LS3 heads up to 4500RPM
You will feel the TQ on a 383 over an LS3 and because you now have a forged bottom end it can take a lot more abuse (unless you use crappy Chinese components) and that means more RPM reliably and if you watch the compression you can supercharge for outstanding results
But its going to cost you more to do your 383 than buying a crate because as said you sell the 5.7 pretty easily if it runs well.
I build a fair amount of every combo LS and if I had a 5.7 that was not tired - I would drop and SC on it and that 125+HP and even stock 100 FT Lbs TQ would outperform the crate engine for less money at 9Lbs boost and way less headaches and its easy labor wise - but does require other mods and a tune depending on your ECM that can be cheap - hard or replace it
Since I do these all the time - I can say 100% whatever you think you are gonna spend on a crate or stroker job - add 50% - you will have pieces you will forget or want to upgrade -
In any case no matter how you go ....you will have to upgrade the fuel system and thats not cheap, you probably will want to replace thr radiator and fans - More HP=more heat and you will have problems you never had. More HP - bigger clutch and as others have said - drivetrain needs to be considered as well as tires and it goes on and on - Catch can, bigger Air filter (more CFM) Bigger throttle body (free hp kinda) Probably swap thr ECM for something more modern and better tuning. Headers on Any chose you make should be at least 1 7/8 most 5,7's are 1.5" or 1 5/8 all those pieces make or break a build power wise .. I could go on I fix these issues daily ...
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