running rich question

[bobo2986]

if I install a walbro 255lph fuel pump in my GSX without an afpr or afc will I run too rich? thanks for any comments

 

[L2RTSiAWD]

A little but not too much. You really want an AFPR at least for max performance.

 

[bobo2986]

ok thanks, does anybody know of a website that sells an afpr that I could buy?

 

[samuraitekno]

it makes you stinking rich if you own a 1g. damn... destroyed all my seals.

 

[DSMNightmare]

IT is really car specific. Right now I'm running rich but I only have the boost @15psi and the AFC is not leaned out enough. Usually I run just fine though with no idle problems or anything.

 

[DrZiplok]

For the zillionth time, the problem is the 255lph high pressure pump combined with the stock FPR's small bypass port.

There is no tuning that can be performed to "fix" the problem; the only thing you can do is move to a regulator with a larger bypass port. It could easily be a non-adjustable regulator, if such a thing existed; the key issue is its ability to bypass enough fuel to maintain the desired pressure.

For the original poster - you don't have the mods to justify a 255lph pump. A 190 would probably do you just fine unless you have a very aggressive upgrade path planned for the near future.

And it's spelled "Tein".

 

[UltraImports]

So in relation to 1/4 mile time, how far can the 190 go?

 

[DSMNightmare]

For the zillionth time, the problem is the 255lph high pressure pump combined with the stock FPR's small bypass port.

OK, I would agree with you but the last time someone told me be that it was my FPR that was causing my idle to be rough and running way to rich they were wrong. When I crawled under the dash I found that they had hooked the AFC up wrong. Thats why now I do my own installs of things like that. The reason I say it is car specific is because I ran the T-25 with a 255hp and had no problems other than running a little rich but not enough to cause any major problems. I know several folks who hae run them with no problems whatsoever without a FPR and I have also met folks that have had several problems. Give the FPR a shot, but I would look and see if it might be something else as well. One thing that can can cause you to run stupid rich is the 02 sensor under the hood. Sometimes this will not give a check engine light but will still be bad. When mine went bad it was like 5mpg and ran like crap. I would check that before spending the money on a FPR.

 

[bobo2986]

The Supra TT fuel pump is capable of pumping a larger volume of fuel but at a lower pressure so would I be able to use that without an AFPR and not run rich?

(hope that made since)

 

[bobo2986]

The Supra TT fuel pump is capable of pumping a larger volume of fuel but at a lower pressure so would I be able to use that without an AFPR and not run rich?

at a lower pressure than the walbro 255 fuel pump I mean, sorry

 

[pneumo]

The standard Denso upgrade pump is good enough for 11's.