Parts Check and Advice
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Teching In
Joined: Oct 2015
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Parts Check and Advice I recently scored a free lq4 out of a 2005 or 06 Express van that a buddy's dad's employee totaled.
I bought 823 heads, and had them milled 0.030 to get them around 65cc in hopes of bumping compression to around 10.2:1 (btw, does anyone know the factory head thickness? I would like to check to see how much has really been shaved off considering I bought them used). Here are my questions:
I'm planning on running around .620 lift. I don't think I'll have any PTV issues due to the dish/valve relief pistons. I'm planning on running Comp Cams 372lbs beehives. Do I need to replace the factory lifters? I've heard of lifters failing before, but I never found out why.
My pistons poke out of the hole about 0.010", making the optimum head gasket thickness around 0.045". That being said, I can't find a gasket on Summit that's smaller or equal to 4.020". So how much larger diameter can I run for the head gaskets?
I bought 823 heads, and had them milled 0.030 to get them around 65cc in hopes of bumping compression to around 10.2:1 (btw, does anyone know the factory head thickness? I would like to check to see how much has really been shaved off considering I bought them used). Here are my questions:
I'm planning on running around .620 lift. I don't think I'll have any PTV issues due to the dish/valve relief pistons. I'm planning on running Comp Cams 372lbs beehives. Do I need to replace the factory lifters? I've heard of lifters failing before, but I never found out why.
My pistons poke out of the hole about 0.010", making the optimum head gasket thickness around 0.045". That being said, I can't find a gasket on Summit that's smaller or equal to 4.020". So how much larger diameter can I run for the head gaskets?
I recently scored a free lq4 out of a 2005 or 06 Express van that a buddy's dad's employee totaled.
I bought 823 heads, and had them milled 0.030 to get them around 65cc in hopes of bumping compression to around 10.2:1 (btw, does anyone know the factory head thickness? I would like to check to see how much has really been shaved off considering I bought them used). Here are my questions:
I'm planning on running around .620 lift. I don't think I'll have any PTV issues due to the dish/valve relief pistons. I'm planning on running Comp Cams 372lbs beehives. Do I need to replace the factory lifters? I've heard of lifters failing before, but I never found out why.
My pistons poke out of the hole about 0.010", making the optimum head gasket thickness around 0.045". That being said, I can't find a gasket on Summit that's smaller or equal to 4.020". So how much larger diameter can I run for the head gaskets?
I bought 823 heads, and had them milled 0.030 to get them around 65cc in hopes of bumping compression to around 10.2:1 (btw, does anyone know the factory head thickness? I would like to check to see how much has really been shaved off considering I bought them used). Here are my questions:
I'm planning on running around .620 lift. I don't think I'll have any PTV issues due to the dish/valve relief pistons. I'm planning on running Comp Cams 372lbs beehives. Do I need to replace the factory lifters? I've heard of lifters failing before, but I never found out why.
My pistons poke out of the hole about 0.010", making the optimum head gasket thickness around 0.045". That being said, I can't find a gasket on Summit that's smaller or equal to 4.020". So how much larger diameter can I run for the head gaskets?
2. Cam lift has nothing to do with piston-to-valve clearance. The opening/closing events of the valves affect PTV clearance. That said, what cams specs are you looking at going with (duration/LSA). This will let people determine if you'll have issues.
3. Go with the smallest gasket bore you can find that are bigger (diameter) than your cylinders......that also comes in the thickness that you want.
KW
Thread Starter
Teching In
Joined: Oct 2015
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I haven't spec'd a cam yet. I'm looking for mid range power and an old school sound. The heads flow well at .620, so I'll be looking for lift around there, but for duration, I don't know where to begin.
As for my lifters, do I need to replace them? I've heard some places that a new cam needs new lifters, but I've only known that to be true with flat tappet.
As for my lifters, do I need to replace them? I've heard some places that a new cam needs new lifters, but I've only known that to be true with flat tappet.
TECH Addict
Joined: Aug 2005
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From: Monroe,NY
head gasket .045 http://www.summitracing.com/parts/tf...make/chevrolet
The dish in the piston doesn't help with ptv because the valve will still hit the high part of the piston.
The dish in the piston doesn't help with ptv because the valve will still hit the high part of the piston.
