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Check out the exhaust valves on my PRC heads...

Old Dec 21, 2010 | 11:58 PM
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Default Check out the exhaust valves on my PRC heads...

Well i got my LQ9 swapped in this weekend, and i was thinking about putting my PRC heads on it later, but when i had the 4.8 on the stand i looked at the exhaust valves, they are white and crusty... All of them look like that and all the spark plugs were white too. Tell me this is not normal...

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Old Dec 22, 2010 | 01:22 AM
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My guess is running lean as hell or fuel additives. Maybe E85? Not sure what color it leaves behind.
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Old Dec 22, 2010 | 01:43 AM
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It's not normal. Send them to me for analysis.
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Old Dec 22, 2010 | 06:43 AM
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I've seen stock heads come off stock engines look like that Corey. I know you're on top of your tuning. I say disassemble them, inspect everything, re-lap all the valves and clean them up and put them on the 6L without thinking twice.
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Old Dec 22, 2010 | 07:23 AM
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Originally Posted by silver-mod-o
I've seen stock heads come off stock engines look like that Corey. I know you're on top of your tuning. I say disassemble them, inspect everything, re-lap all the valves and clean them up and put them on the 6L without thinking twice.
My Radix'd 6.0L looked almost like that when I pulled it. I took some acetone and tried to wipe the valve stems off however the color didn't change. I did not run lean at WOT however did run a 50/50 methanol mix with pump 93 (usually a 10% ethanol blend) and the rare occasion of C16 for the track.

I hope an engine builder chimes in here as I am all ears on this one.

Last edited by krambo; Dec 22, 2010 at 07:25 AM. Reason: spelling
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Old Dec 22, 2010 | 07:44 AM
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Looks pretty much like what I saw on my 5.3, never worried much about it and nothing has melted down yet. Never been lean either and about all I can get is 93 octane with a 10% methanol.

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Old Dec 22, 2010 | 07:49 AM
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Originally Posted by krambo
My Radix'd 6.0L looked almost like that when I pulled it. I took some acetone and tried to wipe the valve stems off however the color didn't change. I did not run lean at WOT however did run a 50/50 methanol mix with pump 93 (usually a 10% ethanol blend) and the rare occasion of C16 for the track.

I hope an engine builder chimes in here as I am all ears on this one.
X2 on my Radix'd SSS looking the same..but I ran a mix of 91/110 vp ...Interested on reason as well....
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Old Dec 22, 2010 | 08:51 AM
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lap them and throw em' on. you could have saved yourself alot of grief by doing the head swap on the engine stand.
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Old Dec 22, 2010 | 09:00 AM
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Yea why didn't you put em on while the engine was out ? Its not anywhere near as fun doin it in the truck
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Old Dec 22, 2010 | 09:55 AM
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Originally Posted by silver-mod-o
I've seen stock heads come off stock engines look like that Corey. I know you're on top of your tuning. I say disassemble them, inspect everything, re-lap all the valves and clean them up and put them on the 6L without thinking twice.
Cool, ya i never ran it lean intentionally, however i did have a 02 sensor die on me and I ran it for a couple hundred miles... But I would have expected the damage to be only on 1 side not both. I will take them apart in a little while.

Originally Posted by Bigredmariner
Looks pretty much liked what I saw on my 5.3, never worried much about it and nothing has melted down yet. Never been lean either and about all I can get is 93 octane with a 10% methanol.
Well that is good to hear.

Originally Posted by TXsilverado
lap them and throw em' on. you could have saved yourself alot of grief by doing the head swap on the engine stand.
Originally Posted by Bumpers
Yea why didn't you put em on while the engine was out ? Its not anywhere near as fun doin it in the truck
Well i wanted to take them apart and have them checked out prior to putting them on my new motor. The old motor used some oil and it started using oil when i put the heads on...
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