tommy260z Posted July 10, 2009 Share Posted July 10, 2009 I recently assembled and installed a P90 head for my L28ET. The former head was an N42. The swap went well, all timing, etc seems to be set up. But the fuel pressure is suddenly sky high. Resting, it sits somewhere around 32psi (like it did with the N42) but as soon as the fuel pump is activated the needle is pinned to the max (60psi). The old set up would idle somewhere around 43psi and rise with revs. I'm pretty confused by this unexpected pressure. Is higher fuel pressure something somehow inherent with the combustion chamber design of the P90? Also, the fuel pump by the tank was installed by the former owner and doesn't have any apparent markings that I could search. Short of pulling it and dissecting it I'm stuck. Any help would be great... Quote Link to comment Share on other sites More sharing options...
naviathan Posted July 10, 2009 Share Posted July 10, 2009 Sounds like a restricted return line to me. Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.