Found light cylinder scuff during upgrade
#12
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Joined: Oct 2005
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From: Waldorf, Md
It definitely needs to come apart. Whatever is causing the problem is not going to get better, only worse. Might be a stuck ring or may have been fuel washed. Like the others have said you need to open up the ring gaps some anyway so be glad you caught it early.
#13
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Joined: May 2010
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From: Cedar Springs MI
No compression is going to 8.5 with chamber porting and a little thicker head gasket. So you guys would recommend a hone and new rings? What is the hot ring setup and gap these days?
#14
I would run a plasma Molly ring and I would do .030 top and .032 second. Last motors I did set top .031 and second .033 run a Napier second. There will be lots of different options on this. To little and you will have problems.
#17
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Joined: Jun 2009
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From: Chicago
I took my engines apart at 250hrs and they do not have anything close to that.
But i`ve had scrapes like that before and it was due to wrong timing, (dizzy got loose) the piston got too hot and expanded scraped the sides. Piston didnt look so good either.
Piston that got too hot , you can see the oil burned :



But i`ve had scrapes like that before and it was due to wrong timing, (dizzy got loose) the piston got too hot and expanded scraped the sides. Piston didnt look so good either.
Piston that got too hot , you can see the oil burned :



#19
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Joined: May 2010
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From: Cedar Springs MI
Stupid question guy’s but I am learning. Will a hone take care of my issues with the new rings or will a hone remove enough material that a different size pistons will be required. I can buy these pistons in a 4.565 overbore stock is 4.560. SRP tells me they will be just fine with 10lb’s of boost. My temptation now is to go to a JE dish piston but my heads are having 10cc removed from the chamber as we type.


