426 oil pressure psi??

1 reply to this topic
  • skydawn19

Posted April 17, 2006 - 07:23 PM


I have a 2001 426 that is over-bored to a 450.

I just replaced my oil pump, and am completely confused about what psi the oil pressure should be at.

It shows:
15 with the choke (cold)
5-8 at idle (warm)
15-20 when it's revved

I know that 450's are in the 50-60 psi range, but I think the 426 should be lower. Is that right? Does the over-bore make any difference?

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  • viking_in_wa

Posted April 17, 2006 - 11:10 PM


being bored over should not make much of a diff. your oil pressure is built from the pump and how strong your main bearings are. I dont know why the 426 and the 450 would be so different in pressure but it sounds worth looking into.

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