Running lean problem with stock FPR??

[fastezz]

Alright I have for fuel a walbro 255lph fuel pump lucas 550cc injectors Apex safc and maft setup, I have the maft set for 550cc injectors and for the AFC I have about +10 all thorugh out 3k rpm`s and up and it still runs a little bit lean, whe I pull my spark plugs the first one is black and the last one is white, do yout hink this means my stock fpr is bad? I have a Big 16g comming in tommorow and a FTS afpr w/ a FP gauge comming later this week in the mail.

The question is is this a common problem with the stock fpr just not holding pressure and causing it to elan out twords the last injector?? Will the FTS afpr fix my problem?
Also what should my fuel pressure be set for with the lucas 550`s?

Thanks for any imput or help.

Ryan

 

[almazan85]

First of all, the fact is u don't wanna run the stock fpr with a 255 pump. It is highly recommended that u use an aftermarket fpr or at leas the b&m. The only reason why u should run the stock fpr is if u have the stock fuel pump or a walbro 190. That might just be your problem. I found out the hard way myself causing the same mistake. Read my vehicle profile and u'll see i pretty much have the same mods as what u posted above.