13.5 stock bore for 426 ?



2 replies to this topic
  • sidkeo

Posted July 10, 2002 - 10:55 AM

#1

any advice on what to expect when replacing 12.5 stock bore w/ 13.5 piston. had to tear down top end-due to pea gravel inside the cylinder.......

how did i do it? well, hit a (1ft or so) vert jump and landed endo style in gravel at badlands.com (attica,in). proceeded to pickup the bike and start it. wouldn't start after a couple kicks. few minutes later, the kicking didn't need any decomp help. next day, kickstart wouldn't even move w/ or w/o the kickstart. tear proved the mess inside-have pics if anyone interested

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  • thumper4life

Posted July 10, 2002 - 11:38 AM

#2

im just guessing here, but do you mean 13.5 to 1 compression ratio instead of 12.5 to 1? :)

but if thats what you mean, then you can expect more power through out the range, most likely race gas (jetted properly) will be your best bet for fuel

[ July 10, 2002: Message edited by: thumper4life ]

[ July 10, 2002: Message edited by: thumper4life ]

  • Boit

Posted July 11, 2002 - 10:18 PM

#3

Ditto on thumper4life's post. As an addendum, the race fuel will be needed to take advantage of the increase in power and more importantly, the increase in heat. As he stated, jet it correctly or you will be miserable. VP C-12 would ge a good choice and is easy to jet. VP MR2 or maybe even MR1 might give the best overall performance once jetted crisp.





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