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Old 08-17-2017, 08:59 PM   #1
Kaisen
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SR20VE valve chipped off

Hi guys,

I bought a Supertech valve train set and got it installed roughly around this period last year. A few days ago, I was running on 3 cylinders and no compression in it so I took off the head and found that the one of the exhaust valve had chipped off. Any idea what could cause this to happen? Tuning issues? Quality?

Thanks in advance

https://ibb.co/iTo2Ma
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Old 08-18-2017, 08:53 AM   #2
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What springs are you running, did you get a new valve job done when installing the valves, what does the seat look like, and why's it so oily in that chamber? Were you burning oil?
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Old 08-18-2017, 06:54 PM   #3
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I was running on Supertech valve train set with 94lb springs with stock P11 cams. I brought the head to the shop to get the valves professionally installed. I have no idea how the seat is supposed to look like lol. I'll get a picture later too. Yes, it was burning engine oil in cylinder 3, that would be the valve seals or the piston rings right? Would improper installation of valve guide cause engine oil to leak into the combustion chamber?

Last edited by Kaisen; 08-18-2017 at 10:17 PM..
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Old 08-18-2017, 10:32 PM   #4
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What pistons are you running and what does the damaged cylinder and piston look like?
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Old 08-18-2017, 10:45 PM   #5
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Im running CP VE pistons 86 bore. 9.0 compression, Tomei headgasket 1.5mm. Cylinder and piston looks fine to me. Are the valve seats changeable for VE head? I dont think the valve seats look good. Attached are images for piston and cylinder and valve seat. This should be a burnt valve?

https://ibb.co/nnJ2p5
https://ibb.co/dbNTU5
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Old 08-18-2017, 10:54 PM   #6
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Added a picture circling out the damaged valve seat



https://ibb.co/jTfF95
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Old 08-18-2017, 11:28 PM   #7
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What's the spark plug look like that was in that cylinder? Right now it seems that you just sucked up something through the intake and it hammered the exhaust valve and seat on the way out.
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Old 08-22-2017, 07:39 PM   #8
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Spark plug looks okay except its coated with oil lol. I couldnt find anything in the turbo though.

This was a SR20VE conversion. I didnt immediately bring it for tuning after running in the engine, that might have caused it to run rich and leave some carbon deposits around the valve creating an improper seal between the valve and valve seat. Is this possible?
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Old 08-22-2017, 07:41 PM   #9
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Spark plug looks okay except its coated with oil lol. I couldnt find anything in the turbo though.

This was a SR20VE conversion. I didnt immediately bring it for tuning after running in the engine, that might have caused it to run rich and leave some carbon deposits around the valve creating an improper seal between the valve and valve seat. Is this possible?
Possible, just highly unlikely, being that you broke the exhaust valve on the edge that's closest to the piston what was the piston to valve clearance on this build?
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Old 08-22-2017, 07:46 PM   #10
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I couldnt remember though, but no issues with the clearance between piston and valves. Guess I'll rebuild it again and see how it goes haha. You're no longer with Mazworx right?
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Old 08-22-2017, 07:48 PM   #11
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I couldnt remember though, but no issues with the clearance between piston and valves. Guess I'll rebuild it again and see how it goes haha. You're no longer with Mazworx right?
Haha, best of luck And correct I'm in sales at Real Street now. If you need some parts let me know!
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Old 08-22-2017, 08:15 PM   #12
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All the best to you too! Will let you know if I need anything
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