LS3 Hollow intake valves and Comp 921 duals
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LS3 Hollow intake valves and Comp 921 duals
How strong are the LS3 hollow intake valves or stock valves in general? I just bought a Comp Cams 921 spring kit and am about to replace the yellow springs on LS3 heads.
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The LS3 valves should only be used in engines without power adders. The material GM uses is very good and the heat treat they use toughens the valves up enough to cope with larger cams and heavier spring pressures are generally not a problem. They don't cope well to high cylinder pressures such as those seen with boost or nitrous.
REV is now selling a hollow stem L92 intake valve and they only recommend they be used with pure n/a applications.
Richard
REV is now selling a hollow stem L92 intake valve and they only recommend they be used with pure n/a applications.
Richard
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Ah crap. When you speak it's gospel, which means I need new valves.
$850 for LS3 heads, $280 for 921s, haven't sold my old heads yet, and need new valves.
$850 for LS3 heads, $280 for 921s, haven't sold my old heads yet, and need new valves.
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I figured I may upgrade to a C6 in a couple of years and swap motors, so went with the forged LS2 with custom Diamond pistons with .060" thicker ring lands. Looked for L92 heads, found the LS3 heads, LS7 lifters, L76 intake, LS2 throttle body, and the 921 springs.
My forged LS1 with the WCCR stg 2 blower heads and 14psi was at 650rwhp, I'm wondering what the new setup will make. I also upgraded the fuel system to 8an and Aeromotive parts as well.
My forged LS1 with the WCCR stg 2 blower heads and 14psi was at 650rwhp, I'm wondering what the new setup will make. I also upgraded the fuel system to 8an and Aeromotive parts as well.
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A big thanks to Bruce @ PowrMax - I bought the heads from him and he's swapping Manley stainless intakes for my hollow LS3 valves (and a few bucks)!