Piston size question?

2 replies to this topic
  • Garysyz400

Posted December 11, 2001 - 08:04 PM


Are there any problems using a 13.5 to 1 piston versus a stock 12.5 to 1 piston. Such as valve clearance, heat, etc.?? When I ordered a top end today I was given the option and chose the 13.5, but am concerned if I made a bad choice. Any help would be greatly appreciated.

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  • DaveJ

Posted December 12, 2001 - 08:42 AM


Measure the old with the new and you'll most likely find that the clearance will be the same.

And piston manufactures usually don't build pistons that people can't use with stock cams.

As for heat, yes. More of it, but you should be fine.

I would be more concerned about octane values.

And what sort of cylinder prep work did you have in mind? Is this a standard size piston, or is it over?


  • Looped_Out

Posted December 12, 2001 - 05:18 PM


Don't go with Wiseco.

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