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Something that's been missing. Whar FPR?

EfiniX

Well-known member
Joined
Oct 18, 2012
Messages
647
Location
portland, or
As i consider what next, I am faced with a question that I don't know the answer to. I've got a stock FPR and rail along with my high-flow pump and 950FIC's.

How is this holding me back?
 

transparentdsm

Well-known member
Joined
Jul 27, 2011
Messages
3,690
Location
Cherry Hill, NJ
I personally don't really think it is, you may want to think about a higher flowing fuel filter and a larger feed line from the filter to the rail. the stock rail is rather large and the stock FPR may be an issue if its older. It could be starting to fail.
 

GSTwithPSI

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Joined
Jan 1, 2012
Messages
3,460
Location
SoCal
The stock rail is fine from a power standpoint. Although, on E85, I've had others tell me the coating in the stock rail flakes off and causes problems. I've yet to see this happen on my car, however, and I inspect the rail often.

The stock FPR is holding you back because you don't have a way of knowing or regulating your fuel pressure, which typically leads to an inconsistent tune. An AFPR is one of those basic building block kind of mods, IMO. It's not one I'd ever skip out on, especially considering how cheap they are.
 

EfiniX

Well-known member
Joined
Oct 18, 2012
Messages
647
Location
portland, or
yeah, I was figuring... Not sure why the PO didn't put one in, and now I"m wondering why I haven't done so yet, either.

When I do, it seems as though the norm is to set it to 42.6psi. I believe our cars are stock @ 37psi. If that change is made, I would wager that I'll need to tweak some other bits to get everything running right...
 

slugsgomoo

Well-known member
Joined
Oct 16, 2003
Messages
3,776
Location
Tacoma, WA
with the stock FPR and a big pump, your injectors aren't behaving like 950's at idle, but potentially much, much bigger. When I had a stock FPR and a walbro 255 on my dsm I found that not only did it smell very rich at idle, my crank case seemed to smell gas-ish fairly quickly (so I did short oil changes). I've heard rumors from v8 guys that out of control idle fuel pressure can wash down cylinder walls, contaminate oil & cause increased wear, but I never really dug into it further.

Frankly I think an AFPR should be a requirement if you're going over a walbro 190 /ubbthreads/images/graemlins/dunno.gif
 
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