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I have forged pistons w/ valve reliefs...do I really need to check PTV clearance?

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Old 07-05-2013, 04:43 PM
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Default I have forged pistons w/ valve reliefs...do I really need to check PTV clearance?

Just as the subject says. I will if I need to but really is there a reason for it?

Cam is 229/234 .610/.600 111+4.
Heads are trick flow as cast 220 milled to 60cc chambers.
Old 07-05-2013, 05:50 PM
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With that amount of head milling and cam specs on the slightly more aggressive side, it would be crazy not to. I would definitely check, its very simple.
Old 07-05-2013, 06:40 PM
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Originally Posted by RezinTexas
With that amount of head milling and cam specs on the slightly more aggressive side, it would be crazy not to. I would definitely check, its very simple.
Even with the valve reliefs in the pistons?
Old 07-05-2013, 08:04 PM
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I pulled an old lifter out and took the guts out. I filled it with washers and put the cup back on the top and compared it to the other lifters. It looks like this will work for my solid lifter.
Old 07-05-2013, 08:13 PM
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The reason to check isn't the valve depth. That's more than likely fine. It's the radius of the valve. Coat the valve and piston with oil, put some model clay on there, and check to make sure you have no interference with the radius of the relief.
Old 07-06-2013, 04:51 AM
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Originally Posted by slammin86
Even with the valve reliefs in the pistons?
yes. more than likely you will be ok, but common sense says to just check to be absolutely sure your specific combo checks out.

I have a less aggressive cam than you, less head milling, and Wiseco's with valve reliefs - I'm about 0.250" PTV. Here is my writeup:

http://www.scribd.com/doc/137049285/...RAFT-20-Apr-13
Old 07-06-2013, 10:29 AM
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You probably won't have any issue, but that is why you check.
Old 07-06-2013, 02:01 PM
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Valve reliefs are pretty deep.

Old 07-06-2013, 02:43 PM
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Dude you asked. Everyone told you yes do it. You are arguing with everyone who said to do it. You clearly don't want to. So put your engine together and roll with it. I mean who cares about knowing and being safe when you just want to be a little lazy and not safe.
Old 07-06-2013, 03:28 PM
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Originally Posted by Silver408z
Dude you asked. Everyone told you yes do it. You are arguing with everyone who said to do it. You clearly don't want to. So put your engine together and roll with it. I mean who cares about knowing and being safe when you just want to be a little lazy and not safe.
Relax guy. If you scroll up a post you will see I made a solid lifter. Im gonna check.
Old 07-06-2013, 09:07 PM
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What kind piston are u using?
Old 07-07-2013, 08:11 AM
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My 243's were milled to 57.5cc, and I'm running a 236/242 .630/.630 111 cam. Stock GM valves.

I too have forged slugs with .175 depth valve reliefs, and took the time to mock it up and check.

Doesn't hurt to check, especially for any radius issues, but I think you'll be just fine.

Old 07-07-2013, 08:28 AM
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I don't think there's any way in hell you'll have to.

AFR 205's at 59cc (stock 15* valve angle)
and a bigger cam than yours.

Stock pistons... no flycutting
Old 07-08-2013, 05:19 AM
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Originally Posted by Go5.3tt06
What kind piston are u using?
They are mahle.

Originally Posted by HeavyMetl
My 243's were milled to 57.5cc, and I'm running a 236/242 .630/.630 111 cam. Stock GM valves.

I too have forged slugs with .175 depth valve reliefs, and took the time to mock it up and check.

Doesn't hurt to check, especially for any radius issues, but I think you'll be just fine.

God to hear.

Originally Posted by dr_whigham
I don't think there's any way in hell you'll have to.

AFR 205's at 59cc (stock 15* valve angle)
and a bigger cam than yours.

Stock pistons... no flycutting
LOL wow. How close are you to hitting?
Old 07-08-2013, 09:40 AM
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i have stock LS3 heads milled only slightly and wiesco pistons with 3cc valve relieves and an EPS 236/242 .629"/.629" and i checked just to be on the safe side. Wouldn't you rather check it now, and know its right, then to go to turn the motor over and think it's right?



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