Upgrading ls2 with ls3 heads
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Upgrading ls2 with ls3 heads
Have a couple questions about my new project. I want to install a set of ls3 heads and intake on my ls2 with a new tune. ive been told to mill them 30mills to get the same compression as my stock ls2 heads. I intend to install a cam at a later date but dont want to do it just yet or know if im gonna be using this same set of heads. so my questions and cam choice dont apply
my question is how much more could or should i mill them to make more power without flycutting my pistons with a stock cam?
also is it worth just to throw on 1.8 roller rockers and leave them at the stock ls2 compression then not to have 1.8 roller rockers but high compression?
my question is how much more could or should i mill them to make more power without flycutting my pistons with a stock cam?
also is it worth just to throw on 1.8 roller rockers and leave them at the stock ls2 compression then not to have 1.8 roller rockers but high compression?
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From: S. Jersey .............. Low 11sec club
St. Jude Donor '11
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From: Livonia MI
Got a few simple things to throw into the mix. Probably better just pulling the LS2 factory intact and dropping in an LS3. Probably better to sell your current LS2 car and get a later model factory equipped LS3 model. Start messing with things and you're gonna end up with a bastard, actually hurting the resale value. If keeping both motors stock, be darned if I can tell the perfomance difference on the street. If planning on an engine build, then LS3, as the L92 head flow's hard to beat.
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^thats retarded. He wants to mod his corvette so you tell him to sell it and buy a newer one for more $$??
The LS2 is a great motor that responds well to mods. No need to buy a new car just because you want some more power.
The LS2 is a great motor that responds well to mods. No need to buy a new car just because you want some more power.
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I would say that he is going in the right direction. And that was good advice about milling the l92 heads .30. I have the 230/234 with .20 milling with the rest of it stock...... and did not have to flycut with this milling. Now, I want to mill my heads at .30 just as they said.....to bring the compression. I really believe that I am missing at least 20 rwhp. With that in mind I probaby have to flycut. Actually, I am getting a new set of L92 heads
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From: Kearney Nebraska
The Selling your Ls2 for a Ls3 sounds like a terrible idea IMO!! Honestly if staying with, N/A setup I'd keep the 243's you have on there!! Maybe have them ported, then add the cam! The LS3 heads are a good design especially in a F.I. setup. But the smaller engine Cubes you run them on the less they respond due to their HUGE Intake runner! A good ported set of 243's will perform equally/if not better than a set of L92's on your stock cube LS2 N/A. If you plan on boosting the car the Huge intake runner of the L92's is great. Check out some of the LS2 Goat on the ls1gto.com forum. Alot of them are making good power on 243 heads.
Just my .02cents. But i would find it hard for Tony Mamo from AFR or Brian Tooley from TEA to disagree with this statement.
This is why Trickflow/AFR used 215/205cc heads is some good 500whp LS1's compared to the 227cc ported 243's. The smaller runner could match the same flow numbers of the ported 227cc LS6 heads but had twice the port velocity on a smaller 205cc runner. FYI the L92s have a 262cc runner IIRC.
Just my .02cents. But i would find it hard for Tony Mamo from AFR or Brian Tooley from TEA to disagree with this statement.
This is why Trickflow/AFR used 215/205cc heads is some good 500whp LS1's compared to the 227cc ported 243's. The smaller runner could match the same flow numbers of the ported 227cc LS6 heads but had twice the port velocity on a smaller 205cc runner. FYI the L92s have a 262cc runner IIRC.
Last edited by 06x6spdGTO; Aug 23, 2011 at 10:06 PM.
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However, anytime that you install a cam you should check the PV clearance regardless. Just keep this in mind that my L92 heads were not ported. So, you could be back on the drawing board on that issue.
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what head gasket thickness are you running?
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Stock head gaskets. If you start to thin the head gaskets you may be looking to flycut.
I think the magic number is .030 milled heads and .040 thin gaskets. If you are planning on doing that to raise the compression then you best think about flycutting. But this is the route I am going to take in the future. My mechanic knows how to flycut with his experience......on top of that other mechanics have call him to use the flycut instrument. But if you listen to Spinmonster in order for his 230/234 to optimize, you need to raise the compression to get the full potential. I really love this cam. It is perfect for me. With the new L92 CNC heads and with my current 230/234, I believe that I should dyno between 450/460.
I think the magic number is .030 milled heads and .040 thin gaskets. If you are planning on doing that to raise the compression then you best think about flycutting. But this is the route I am going to take in the future. My mechanic knows how to flycut with his experience......on top of that other mechanics have call him to use the flycut instrument. But if you listen to Spinmonster in order for his 230/234 to optimize, you need to raise the compression to get the full potential. I really love this cam. It is perfect for me. With the new L92 CNC heads and with my current 230/234, I believe that I should dyno between 450/460.
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He wasn’t talking about you Cary, he was referring to the reply earlier that someone told a guy to sell his vette and buy one with a ls3. Think about it man you have a ls3 and he’s talking about a ls2 lmao
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