nismology

iTrader: (8)

To be more specific is anyone using that fuel pump with stock injectors/FPR? What fuel pressures are you seeing at idle and at WOT?? Thanks alot.




Mike

Bluebird

iTrader: (4)

I'm using the 190lph pump, not sure if its low or high pressure though. I just installed it and never checked FP or anything. Car feels and runs the same.

nismology

iTrader: (8)

Thanks for the reply. What's really worrying me is the possibility of running too rich at WOT. How does your car feel at WOT with the nitrous off?

Edit: You might be supercharged

Shadow

iTrader: (15)

I'd look for JaimeCBR, he's got a Lexus now, but he had (still has at the shop) a nitroused Maxima. I know he had the 190 on his car. He swapped that in after running too rich with the 255.

Bluebird

iTrader: (4)

Unfortunately, I'm not SC'd. Mmmmm, juicy boost.

The car feels geat at WOT, same as it ever was.

Bags

iTrader: (3)

I had the 255 lph pump installed before I had boost. Idle changed to 40psi and WOT to ~46psi

Performance suffered I am sure. i could not tell a difference. I drove like that for~500 miles

nismology

iTrader: (8)

Thanks for the replies fellas. Guess im going to go with the 190 LPH low pressure pump. Anybody know where i can find one for cheap?? And specifically to Bluebird, do you have the part # of the pump?? Cus i keep finding the 190LPH for the 89-94 maxima and none for the 4th gen. Thanks in advance.

Bluebird

iTrader: (4)

Go to: http://www.autoperformanceengineering.com/

You only need the pump and they don't list a specific pump for the 4th Gen but its the same as the 2nd Gen DSM. The kit with the correct pump is FPD004, which runs ~$88.Send them an email and ask what the GSS# is for the pump in that kit and you will get just the pump cheaper ($80) because it comes without filter, which won't fit anyway because its for the DSMs.

nismology

iTrader: (8)

Thanks for the link. So should i get the filter from the stealership or can i just clean it and reuse it? Also did you reuse the retaining/mounting ring? Thanks again.

Bluebird

iTrader: (4)

I just used the filter over again, its just basically a piece of fabric designed to stop larger particles. I would think that as long as you change the filter under the hood, you'll be fine. But if I had it to do over again, I would of replaced it just because I was in there, provided the dealer doesn't want a lot of $$$ for it.

I got a new mounting gasket/ring, only a couple of bucks.

1MAX2NV

iTrader: (5)

You will run rich with 190lph walbro pump without adjustable fuel pressure regulator. I know because that was exactly what I did and I had tons of issue trying to tune my nitrous kit. I finally got a FPR and it made life so much easier. It was running aleast 8psi too much at idle. It was killing my mpg and I had black smoke coming out of tail pipes during WOT. FYI, no boost on my car, just nitrous.

nismology

iTrader: (8)

Dammit. That's not what i wanted to hear. Thanks for the info though. I have a few questions for you:

1. Which fuel pump should i use as an OEM replacement? The walbro 155 LPH pump?? I'm not about to drop over $200 for an OEM pump JUST YET.

2. How many LPH does the 4th gen OEM fuel pump flow??

3. Were you using the regular 190 LPH or the high pressure 190??


Thanks in advance.

1MAX2NV

iTrader: (5)

I have no idea what LPH the OEM pump flows but it's good enough for most NA mods. I was using Walbro 190LPH non high pressure. I needed the volume but I didn't need the high pressure. I'm running wet nitrous kit. Why do you need to upgrade your fuel pump? With upgraded fuel pump, you will get high volume no matter what. Most OEM regulators can't handle all the volume or high pressure of a upgrade fuel pump. Buy fuel pump only when you need it.

nismology

iTrader: (8)

Well my OEM fuel pump failed. Sorry, i forgot to mention that. I was just wondering if there was an aftermarket OEM replacement pump out there. The cheapest I found the OEMer for was ~$215.

nismology

iTrader: (8)

OK I'm getting mixed opinions here and some responses are in direct contradiction of each other.

Bags says that he got 40 PSI at idle with the 255 LPH pump (high pressure im sure) and you say that you were running at least 8 PSI too much at idle with the 190 LPH pump??? Something doesn't add up here. That would mean you were seeing around 44 PSI at idle. How could you possibly be seeing more fuel pressure at idle than him when he had a 255 LPH??? Are you sure your stock FPR was operating properly cus I've never heard of a 190 LPH pump bumping up the base fuel pressure 8 PSI.

On top of that Bluebird said that he's running fine with the 190 LPH when he's off nitrous. I don't know what to think now.

Bluebird

iTrader: (4)

Yeah, I'm not having any problems, no black smoke, running as strong as ever.

But now I want to check my FP because of 1MAX2NV's post. He just had to go and make me paranoid about it

1MAX2NV

iTrader: (5)

I don't remember the exact fuel pressure at idle with 190lph. I remember it to be somewhere close to what fuel pressure would be at WOT. 43psi give or take few psi. You need to understand what high pressure means when it comes to fuel pump. It means the fuel pump can sustain X amount of GPH(flow volume) at Y amount of PSI (pressure). Bags 255lph HP pump flows close to the same as my 190LPH pump at ~40psi. But his 255lph HP will out flow my 190lph at 90PSI. 255lph HP is design to flow more at higher pressure.

Sure, the car will run with higher fuel pressure. I never said it wouldn't run. But you will run rich, waste gas, poor performance..etc.

Anyway, I have a OEM fuel pump off my 1999 I can sell you if you just need a replacement.

I will bet you $100 that Bluebird is running higher than OEM spec 34psi at idle with 190LPH if he's still using OEM fuel pressure regulator.

1MAX2NV

iTrader: (5)

Oh...just by lowering my fuel pressure back down to OEM spec I gain some HP on the dyno.