Can a LS3 bored to 4.100?
11-05-2010, 12:46 PM
#1
Can a LS3 bored to 4.100? I've been told by a few people that a ls3/l92 can be bored out to 4.100. Is this true and is anyone actually running at this bore? I'm not going to boost and probably not going to NOS (50-100 shot if anything). I won't be breaking over 600 hp with this setup.
11-05-2010, 12:54 PM
#2
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4.08" is about as max you want go N/A.
11-12-2010, 09:12 AM
#5
We have done it before if someone absolutely wants it but we don't recommend it. That's how guys are getting away with running LS7 heads on a LS3 block. You can build an LS3 422c.i. motor going with a 4.100 bore and a 4.00 stroke crank. If any way possible, 4.080" is about as far as we like to go.
11-12-2010, 06:29 PM
#6
I'm not going to stroke it. I'm doing road racing so I can't stroke it and I won't.....so don't bring it up. I'm sticking with a 3.622 stroke and boring it out as much as I can.
John: Are you saying you've done 4.100 before and it worked out well? As long as I don't NOS and boost it should I be okay? I can't break 600 hp due to the transmission in the porsche I'm dropping this into. Roughly, how much of a hp gain did you get from a LS7 vs a LS3 head on the engine? Is there any modifications needed for the ls7 heads or do they just bolt on?
John: Are you saying you've done 4.100 before and it worked out well? As long as I don't NOS and boost it should I be okay? I can't break 600 hp due to the transmission in the porsche I'm dropping this into. Roughly, how much of a hp gain did you get from a LS7 vs a LS3 head on the engine? Is there any modifications needed for the ls7 heads or do they just bolt on?
Last edited by bp944; 11-12-2010 at 06:34 PM.
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12-01-2010, 09:01 AM
#8
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Going form 4.08 to 4.10 is about 4 cubes, and a hand gernade if not sleeved. All for 6-7 hp?
Nitrous on roadracing?
Jon
12-03-2010, 10:33 PM
#9
LS3 max. bore The Gen III blocks and the LS2 have much better sleeve placement in the factory castings than the L92 LS3 blocks have from my experience. The LS2 block can indeed be bored .030" with little risk. If you look at the sleeve flanges on most of these L92 LS3 castings, one side of the sleeve will have a wider flange surface than the opposite side. The sleeve wall will be thin and thick as well. Not a block you want to bore oversize.
Another problem with these blocks is some sleeves are not straight up and down or right angles to the deck. This is not something you can see unfortunately. I see this when I cut out the old sleeves when I sleeve these blocks. They are problematic even when resleeving for this reason.
These blocks can be dry sleeved with Darton Seal Tight dry liners. I dry sleeved two L92 blocks and an LS9 block in the last couple of weeks. The Darton dry liners will go from 4.125" to 4.185" bore. An added benefit is the 5.800" length of the Darton liner, some .350" longer than the stock sleeve for better piston support with stroker cranks. Most guys go with a 4.155" bore which helps unshroud the intake valves and leaves enough sleeve for a good shot of nitrous or boost.
Steve
Another problem with these blocks is some sleeves are not straight up and down or right angles to the deck. This is not something you can see unfortunately. I see this when I cut out the old sleeves when I sleeve these blocks. They are problematic even when resleeving for this reason.
These blocks can be dry sleeved with Darton Seal Tight dry liners. I dry sleeved two L92 blocks and an LS9 block in the last couple of weeks. The Darton dry liners will go from 4.125" to 4.185" bore. An added benefit is the 5.800" length of the Darton liner, some .350" longer than the stock sleeve for better piston support with stroker cranks. Most guys go with a 4.155" bore which helps unshroud the intake valves and leaves enough sleeve for a good shot of nitrous or boost.
Steve
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Steve Demirjian
Race Engine Development
Oceanside, Ca.
760-630-0450
web: www.raceenginedevelopment.com/
e-mail: race-engine-development@***.net
Steve Demirjian
Race Engine Development
Oceanside, Ca.
760-630-0450
web: www.raceenginedevelopment.com/
e-mail: race-engine-development@***.net
12-03-2010, 10:37 PM
#10
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The Gen III blocks and the LS2 have much better sleeve placement in the factory castings than the L92 LS3 blocks have from my experience. The LS2 block can indeed be bored .030" with little risk. If you look at the sleeve flanges on most of these L92 LS3 castings, one side of the sleeve will have a wider flange surface than the opposite side. The sleeve wall will be thin and thick as well. Not a block you want to bore oversize.
Another problem with these blocks is some sleeves are not straight up and down or right angles to the deck. This is not something you can see unfortunately. I see this when I cut out the old sleeves when I sleeve these blocks. They are problematic even when resleeving for this reason.
These blocks can be dry sleeved with Darton Seal Tight dry liners. I dry sleeved two L92 blocks and an LS9 block in the last couple of weeks. The Darton dry liners will go from 4.125" to 4.185" bore. An added benefit is the 5.800" length of the Darton liner, some .350" longer than the stock sleeve for better piston support with stroker cranks. Most guys go with a 4.155" bore which helps unshroud the intake valves and leaves enough sleeve for a good shot of nitrous or boost.
Steve
Another problem with these blocks is some sleeves are not straight up and down or right angles to the deck. This is not something you can see unfortunately. I see this when I cut out the old sleeves when I sleeve these blocks. They are problematic even when resleeving for this reason.
These blocks can be dry sleeved with Darton Seal Tight dry liners. I dry sleeved two L92 blocks and an LS9 block in the last couple of weeks. The Darton dry liners will go from 4.125" to 4.185" bore. An added benefit is the 5.800" length of the Darton liner, some .350" longer than the stock sleeve for better piston support with stroker cranks. Most guys go with a 4.155" bore which helps unshroud the intake valves and leaves enough sleeve for a good shot of nitrous or boost.
Steve
good information!
