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Cheetah squish and pitting on pistons and domes


Cali421

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Lol no one answered my questions. So will I be able to just hone and replace this pistons /rings ?

 

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What did the bore look like? No major scaring? Typically with nikasil you just do a fast diamond hone only if it's needed, and just keep chucking new Pistons and rings in there. Try to avoid honing it if possible as it's just a coat of plating in there.
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I have honed nikasil many times with no issues, the key is finding the rite home shop with the rite home. Have them put a lil pattern in there to knock the glaze off and so the new rings will seat properly. Make sure there are no areas where there was metal sharing going on

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It looked ok just shiny, I haven't took a real good look yet. I'll take a better look tonight and get some pics. Thanks

 

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If you can't feel any big grooves throw new pistons in it and go. Can maybe clean that dome up with scotch bright as well.

 

 

Edit: looked back at the pic. Piston may be usable too.

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Check the thickness of your cylinder base gasket when you pull it apart.  Cub cylinders (I assume PV cylinders are simmilar) are made to run with a .012" thickness base gasket.  I has a similar squish issue (too big) because I had a stock base gasket witch is around .030" with cub cylinders.  Around .040" squish is ideal.  That said, I doubt a squish around .060" would cause detonation issues, but it might explain less than expected performance though.  You might try a 1cc larger dome (less compression) or run 110 octane to get rid of the detonation problem.  The crank seal could be your problem, but I had a motor that detonated on one side before and it wasn't the crank seal.

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Check the thickness of your cylinder base gasket when you pull it apart. Cub cylinders (I assume PV cylinders are simmilar) are made to run with a .012" thickness base gasket. I has a similar squish issue (too big) because I had a stock base gasket witch is around .030" with cub cylinders. Around .040" squish is ideal. That said, I doubt a squish around .060" would cause detonation issues, but it might explain less than expected performance though. You might try a 1cc larger dome (less compression) or run 110 octane to get rid of the detonation problem. The crank seal could be your problem, but I had a motor that detonated on one side before and it wasn't the crank seal.

Will do thanks, what was causing your's to detonate?

 

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Check the thickness of your cylinder base gasket when you pull it apart. Cub cylinders (I assume PV cylinders are simmilar) are made to run with a .012" thickness base gasket. I has a similar squish issue (too big) because I had a stock base gasket witch is around .030" with cub cylinders. Around .040" squish is ideal. That said, I doubt a squish around .060" would cause detonation issues, but it might explain less than expected performance though. You might try a 1cc larger dome (less compression) or run 110 octane to get rid of the detonation problem. The crank seal could be your problem, but I had a motor that detonated on one side before and it wasn't the crank seal.

Many of the domes in the Cheetahs have a convergant squish band. So even at sixty thou, they still detonate. Yay Trinity.
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Will do thanks, what was causing your's to detonate?

 

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Could have been a few different things, too low of octane, too tight on the squish, overheating and going WOT up the Sand Mountain drag hill too many times.

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