Are most of the fuel pumps from the 02'+ era of Nissan cars, are they interchangeable?And cars like the 350Z/G35 that uses the VQ35, do they use a higher pressure fuel pump? Since i had to gut the pre cats on my MAX i am thinking the VQ35 is sucking and pumping to much air through the system which i think now my A/F ratio is slightly off causing mild pinging under WOT. A guy told me as a suggestion that maybe a higher pressure fuel pump may even things out. I use premium fuel religiously and ever since the gutting of the precats, the car seems a bit weaker on the low end of the spectrum but pulls from mid to redline very well. Car has intake and a custom cat back exhaust.

Suppose to take it to Z-fever in Tampa and he said that a advance in timing (17 degrees) should do the trick as well? What do you guys think?

 

Nobody knows , huh?

 

advance timing will increase pinging if that is really what oyur hereing

by gutting the cats you reduce back pressure which will cause a sluggish low end but increase top end

you need hook up a wideband to check your A/F ratio to see if thats really the problem before replacing random things that are probobly not the problem

 

Also, if you want higher pressure don't change the pump, put in an adjustable FPR. The only reason a fuel pump change will up the fuel pressure is because the stock FPR isn't capable of handling the flow, thats not how you want to increase pressure.

Like subs says get your a/f checked.

 

Thanks guys.....funny you mentioned the FPR , i bumped in to an old buddy of mine and he said the same thing....i guess gear heads think alike.

 

Did you just gut the front precat or did you gut the rear one instead of a y pipe? You should have converted to a fed spec exhaust system instead. The large area of the front precat being open is causing you to loose some low end.

 

No the the two that comes of the front and rear manifold. The rear cat was fine, you could see strait through it. But the front cat filament had huge chunks missing from it and the 2nd precat was slightly melted due to it being of a metal substrate. Sure enough huge chunks were clogging up the flow at the main cat. Cleaned the debrie away and sent pressured air through the main cat to make sure the honeycomb was free and clear of any obstructions.

Would a y-pipe give me back some of my lost back pressure?

This would be next mod after the advanced timing and once i get my A/F ratio checked out.Unfortunately my funds have to go to more meaningful things in my life or else i would buy the headers/y-pipe combo, so i am modding a little at a time.

 

is there adjustable fpr available for our cars?

 

Any max before 02 has a ton of FPR that you can connect. There is a nismo one that bolts on to the stock rail but is too long on one of the connections.

I am not sure on the 02+ maximas since they have a returnless fuel system and the dampener or FPR is in the tank.