400 to 426 conversion, the easy way



48 replies to this topic
  • yz00

Posted April 19, 2012 - 05:54 PM

#41

The 426 piston uses a larger wrist pin, so you'd need the 426 rod
That would allow you to use the 400 crank.


ok so with the 426 cylinder/450 piston and rings you can use the 400 bottom end AND the con rod?
im trying my best to undertsand this all before i make a purchase...

and on top of all that the stock 400 head with decrompres exhast cam..?

Edited by yz00, April 19, 2012 - 06:00 PM.


  • umu24013

Posted April 20, 2012 - 07:05 AM

#42

ok so with the 426 cylinder/450 piston and rings you can use the 400 bottom end AND the con rod?

exactly. 400 bottom end + 400 con rod + 426 jug + 450 (5TJ) piston and rings

and on top of all that the stock 400 head with decrompres exhast cam..?

yes

  • yz00

Posted April 21, 2012 - 03:18 PM

#43

so will the 426 jug bolt up and use teh same gastkets as the 400 jug?

  • potman1980

Posted April 24, 2012 - 06:43 AM

#44

thanks for your help umu2.

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  • umu24013

Posted April 25, 2012 - 09:53 AM

#45

so will the 426 jug bolt up and use teh same gastkets as the 400 jug?

the base gaskets are the same. the cylinder head gaskets are different p/n

  • grayracer513

Posted April 25, 2012 - 10:00 AM

#46

the base gaskets are the same. the cylinder head gaskets are different p/n


The difference in the head gasket is the 95mm vs. 92mm bore size. The bolt patterns are the same between the 400 and 426.

  • yz00

Posted May 05, 2012 - 06:58 AM

#47

ok so one more question on this matter. on my 400 turns out the head is bad. my queston, i already have a 450 piston and a 426 jug but now what should i put on for a head? im guessing the 426 is only going to bolt on and would be best choice?

  • shorey400

Posted November 18, 2013 - 12:06 AM

#48

What is the difference with the 2s2 piston? Would this also work?

  • Billy.salmon

Posted July 03, 2016 - 07:55 PM

#49

I'm new here and know this is an old topic but can you use a big bore 450 piston





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