400>426>426 big bore

3 replies to this topic
  • Goonyz400f

Posted August 06, 2015 - 09:34 PM


If a 426 bore can fit on a 400 then can a 426 big bore fit a 400 aswell

  • hondarider1031

Posted August 20, 2015 - 09:45 AM


With a 426 rod, yes-provided the kit comes with a new cylinder
A bore In kit probably wouldn't work-the 400 cylinder walls are fairly thin

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  • Goonyz400f

Posted August 25, 2015 - 02:22 AM


I was meaning the kits that come with the bore and piston

  • grayracer513

Posted August 25, 2015 - 06:15 AM


Most kits are 3mm overbores to 95mm, which makes it a 426.  You can also do the same thing by using a 426 piston and cylinder, rebuilding the crank with a 426 rod, or by using a 426 cylinder, and a piston from an '03-'09 450.  It's a lot of work for a 6.5% increase in displacement.

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