Big Bore for 426f?

10 replies to this topic
  • 707

Posted October 20, 2004 - 09:48 PM


Is there a way to get it to 450cc? or is there any other big bore kits around? thanks.

  • Derekj426

Posted October 20, 2004 - 10:24 PM


My 426 has a 440 kit on it.. Check out bigbore kits, they got em.


  • Rich_Rohrich

Posted October 21, 2004 - 07:44 AM


Is there a way to get it to 450cc? or is there any other big bore kits around? thanks.

A 2mm overbore (97mm piston) will get you 444cc which is the practical limit for a bore increase on an OEM cylinder. Displacement beyond that would require a stroke change or a recast cylinder like Athena is building.

  • superduper

Posted October 21, 2004 - 10:53 AM


i agree i dont think you would notice 6cc's

  • Chipstien

Posted October 21, 2004 - 06:16 PM


What do people think of the 450 kit from Thumper Racing? :cry:

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  • Harry Paratestes

Posted October 21, 2004 - 06:20 PM


Falicon has a 488 bore/stroke kit. A bit pricey, $2200 or so.


Posted October 21, 2004 - 06:30 PM


Wouldnt buying a 13.5:1 Wiseco piston make up the 24cc's the 450's have? :cry: :cry:

  • felony

Posted October 21, 2004 - 08:13 PM


no,the wiseco piston boosts compression not displacement,i have it and i still wont chase down the 450 on a long straight :cry:

  • Rich_Rohrich

Posted October 21, 2004 - 08:34 PM


no,the wiseco piston boosts compression not displacement,

You can get a 13.5:1 version of the 97mm Wiseco piston that will bring the displacement to 444 after a rebore/replate of the cylinder. If the rest of the engine is done right it will run with the newer 450s .

Here's a dyno chart of SFO's 444 running stock cams (reindexed) and stock valve sizes. At 52 horsepower on pump gas and 54 on Nutec it can stay with the 450s no problem. :cry:



Posted October 22, 2004 - 01:03 PM


Sweet!! :cry: :cry:

  • 01yz426

Posted October 31, 2004 - 11:35 PM


My buddy has a 450 big bore kit on his.... It has blown up twice, but I'll find out where and what he has done to it.

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