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Is this piston useable?

citymunky

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Sep 22, 2010
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Chesapeake, VA
This piston made contact with a valve sometime in its life (Start up), would you use this piston or replace it?


 

ApexHunter

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Apr 25, 2007
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1,992
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Marysville, WA
I'd sh*t can it- not worth it. That gouge will serve as a nice habitat for carbon deposits and become a hot spot, encouraging detonation/pre-ignition.
 

donniekak

Well-known member
Joined
Jan 1, 2009
Messages
748
Location
surprise az
Check that the rings don't get pinched in the land, knock the sharp edge off of it with a detail file and run it. The valve relief cuts are sharper than that dent will be.
The bottom end in my car was in it when I bought it. Eagle/wiseco combo. At some point in time the exhaust valves contacted the Pistons. I spent a couple minutes making sure they weren't sharp, and checked the pin boss skirt area for cracks. They work fine at 40+ psi on e85, and have no knock issues running pump gas at 25 psi with a 35r sized turbo.
 

biglady112

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Joined
Sep 30, 2005
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1,255
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Commerce City, Co
We have made over 800hp with much worse. Smooth/grind the ding down and go nuts. Don't be scared.
 
Last edited:

Mdlimy

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Joined
Apr 30, 2015
Messages
111
Location
Gresham, oregon
Id smooth it out real good and run it. Like Apex said, the burs will cause hotspots and cause det. If it truly happened at start up it shouldn't have done any structural damage to the rest of the piston.
 

EMX5636

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Jun 28, 2008
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1,631
Location
Bucks County, PA
I've cleaned up marks like that with no ill effects. It depends if it's always going to be on the back of your mind. If it will haunt you, replace it. But you can probably beat the snot out of it without issues.
 

TurboTurtle

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Sep 13, 2011
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37
Location
Rotterdam NY
If you have to question it, you shouldn't use it
 

Olson

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Oct 7, 2006
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1,237
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Moreno Valley CA
Clean it up smooth it out and run it.
 

GSX_TC

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Apr 7, 2011
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Location
Houston, Texas
Quoting TurboTurtle:
If you have to question it, you shouldn't use it



^^
What he said.
 

iceman69510

Turn Right Racing
Staff member
Joined
Mar 5, 2001
Messages
10,964
Location
Michigan
Agree it is usable with removing sharp edges.
 

citymunky

Well-known member
Joined
Sep 22, 2010
Messages
1,761
Location
Chesapeake, VA
Thanks for the input guys, I'm not a engine builder so I don't know much about this things.

Looking at the other pistons that were in the block, they all made slight contact with a valve at some point. However the piston pictured above was by far the worst one. I'm just going to use the other set of JE pistons from the motor that was in 733/2k to begin with.
 
Last edited:
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