Fuel pressure regulator and gauges

[LETZRIDE]

When would you need a FPR? and how or what would be involved in going about installing a fuel pressure gauge?

I really just can't seem to scale my injectors up so that my maf calibration is 100% bang on...I'm almost 100% positive it is because I have the injectors set at 36 across the board...I'm thinking they need to be 36.xx or 37 in some of the MAP cells...the only way to find out this info I think is to data log it...but we dont have these sensors in the car stock...

[Blizzard242]

Re: Fuel pressure regulator and gauges

A fuel pressure gauge is easy as hell to install. If you get an electronic one (which I highly recommend) you just screw a sending unit onto the schrader valve, and run the wires up to a "brain box" and then more wires from that go to the actual gauge. You also have to wire up power to the box too which I did from the back of the cigarette lighter to a switch then to the box.

What kind of mods are you really running though? I'm on the stock FPR with around 7lbs of boost and I'm doin fine.

Injectors are dialed in according to injector pressure ratings and fuel rail pressure. You should be able to do this without even running the car assuming you know your fuel pressure at say, idle and WOT. After you've correctly plugged those numbers in, (which I can't even figure out so don't feel bad if you can't either), just tune your MAF using your wideband and error% tables.

[LETZRIDE]

Re: Fuel pressure regulator and gauges

A fuel pressure gauge is easy as hell to install. If you get an electronic one (which I highly recommend) you just screw a sending unit onto the schrader valve, and run the wires up to a "brain box" and then more wires from that go to the actual gauge. You also have to wire up power to the box too which I did from the back of the cigarette lighter to a switch then to the box.

What kind of mods are you really running though? I'm on the stock FPR with around 7lbs of boost and I'm doin fine.

Injectors are dialed in according to injector pressure ratings and fuel rail pressure. You should be able to do this without even running the car assuming you know your fuel pressure at say, idle and WOT. After you've correctly plugged those numbers in, (which I can't even figure out so don't feel bad if you can't either), just tune your MAF using your wideband and error% tables.

I'm cammed and stalled....36# injectors...so I think Im fine as far as getting enough fuel...I just dont know my pressure at idle, cruise, or WOT...I cant seem to get this info from hp tuners, so I am assuming I must buy the sensor and install it...I have tuned my MAF using my wideband and error % tables...and its fairly close...but I'm up to .5 of a point off in some locations under WOT sometimes...I cant count how many tuning runs I've had, and I just can't get the thing perfect...so I believe it is because I have the injectors dialed in at 36 across the MAP board...I've heard you need to scale them properly like 36.xx in each column or your tune will never be 100%

[ssms5411]

Re: Fuel pressure regulator and gauges

36lb injectors are rated at 33lB on our fuel system. Mine are scaled from 33 to 34 and my PE I add .300 from 3200-6000 so it is pretty much dead on for fueling. On my winter tune PE is all zeroed out and it runs fine with a 12.5-12.7 A/F. My command is set at 12.5. Also don't run more than 28 degrees timing in the right bottom of the OCT. tables and watch you overall timing so it doesn't go past 28 at WOT. Also the lower timing cells should be around stock since they won't change your WOT timing, and it won't want to pull mor fuel if the timing is really high. I have my tables setup up and used the scaling on the graph to average the tables out on low and high Oct. , really worked great for me.

[LETZRIDE]

Re: Fuel pressure regulator and gauges

If I hooked up a Fuel pressure gauge, can I connect that to Hp tuners so I can use it for tuning purposes?

[Blizzard242]

Re: Fuel pressure regulator and gauges

I was wondering about that too.. I suppose you could through a similar way that you hook a wideband up to be logged if you don't have the Pro version. You should probably go over to HP tuners forum and ask them. Definitely let me know what they say.

[LETZRIDE]

Re: Fuel pressure regulator and gauges

Well heres a good thread

http://www.hptuners.com/forum/showth...pressure+guage

From what I've read, it looks like you can do it if you buy an analog FP gauge...and apparently there is a preset for the autometer gauges already on hp tuners under the PIDS...

[Blizzard242]

Re: Fuel pressure regulator and gauges

So what I would do is get a voltmeter and measure what my sending unit is putting out and go from there. The wiring wouldn't be hard. I personally would do it from my AC wiring since that doesn't currently exist. Figuring out the voltage from the sending unit to make it a correct sweep in HP tuners would be the only tricky part but that's what the voltmeter is for. It is basically the same way to log a wideband through your EGR or AC.

[LETZRIDE]

Re: Fuel pressure regulator and gauges

there is actually a write up on hp tuners about how to wire it into the EGR...but its for an LS1, not sure if we have the same pin outs...

[Blizzard242]

Re: Fuel pressure regulator and gauges

Just look for a wideband logging tutorial. They'll have info about the egr and ac stuff there.