Where should a fuel pressure gauge and regulator be placed?

[4gfun]

I'd like to add a fuel pressure gauge and a fuel pressure regulator. It is a Galant VR4, so where would the best place to put these items be on a 1g?

Thanks

 

[OakStreetTuner]

I mounted mine about a foot to the left of my brake booster almost near the center of the firewall. I have a fuel lab fpr and Guage and it fits good and looks nice when the hood is up.

 

[4gfun]

Thanks for responding. I should have been more clear.

What I really meant to ask was what does the fuel pressure gauge go inline with (between what points in the fuel system).

Same for the fuel pressure regulator although I suspect that things may be more complicated there because I am not sure what happens with the stock fuel pressure regulator when adding an aftermarket one.

I mounted mine about a foot to the left of my brake booster almost near the center of the firewall. I have a fuel lab fpr and Guage and it fits good and looks nice when the hood is up.

 

[combs-dsm]

You take your stock fpr out and ad on an adapter to fit whatever size hose comes with the for.

 

[4gfun]

Huh?

Also, where does the fuel pressure gauge go? Where is most accurate? Right after it comes off the filter and into the injector rail?

You take your stock fpr out and ad on an adapter to fit whatever size hose comes with the for.

 

[kqodprez]

My fuel pressure gauge mounted on my fpr. I mounted mines on the firewall next to my master cylinder. The fuel pressure regulator goes between the fuel filter and the rail.

 

[Rsawd95dsm]

Im pretty sure the FPR goes on after the fuel rail. So filter, rail, then FPR, then return line. The gauge can go where you want it. People have it right at the begining of the fuel rail or mounted on the FPR itself. The stock regulator goes in thee trash once you're installing a AFPR.

 

[4gfun]

Thanks, so the stock FPR is on the fuel rail at the end of the rail towards the passenger side of the vehicle if I have this right?

Im pretty sure the FPR goes on after the fuel rail. So filter, rail, then FPR, then return line. The gauge can go where you want it. People have it right at the begining of the fuel rail or mounted on the FPR itself. The stock regulator goes in thee trash once you're installing a AFPR.

 

[kqodprez]

Im pretty sure the FPR goes on after the fuel rail. So filter, rail, then FPR, then return line. The gauge can go where you want it. People have it right at the begining of the fuel rail or mounted on the FPR itself. The stock regulator goes in thee trash once you're installing a AFPR.

How can it go on after the rail if the rail is where the fuel ends? WTF

 

[pitbull419]

Its placed at the return end because of pressure drop.

Visual Frequently Answered Questions - Home Page

http://www.dsmtuners.com/forums/articles-engine-fuel/375597-afpr-install-how-video.html

http://www.dsmtuners.com/forums/articles-engine-fuel/338084-aeromotive-afpr-install-install-kit.html

 

[4gfun]

Thanks so far!

Its placed at the return end because of pressure drop.

Visual Frequently Answered Questions - Home Page

http://www.dsmtuners.com/forums/articles-engine-fuel/375597-afpr-install-how-video.html

http://www.dsmtuners.com/forums/articles-engine-fuel/338084-aeromotive-afpr-install-install-kit.html

 

[Rsawd95dsm]

Thanks, so the stock FPR is on the fuel rail at the end of the rail towards the passenger side of the vehicle if I have this right?

Not sure on a GVR4 but whatever way the fuel travels then it should be on the end right before the return fuel line.

How can it go on after the rail if the rail is where the fuel ends? WTF

It needs to regulate the pressure inside the fuel rail so the injectors would have a constant pressure at all times.

 

[WES_393]

How can it go on after the rail if the rail is where the fuel ends? WTF

Use a hose, silly.

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But seriously, the fuel doesn't end at the rail. The excess fuel shed by the regulator is sent through a return line to the fuel tank.

 

[kqodprez]

Not sure on a GVR4 but whatever way the fuel travels then it should be on the end right before the return fuel line.



It needs to regulate the pressure inside the fuel rail so the injectors would have a constant pressure at all times.

So after the fuel enters the fuel rail where does it go? The fuel rail is the last place fuel goes before it hit's the injectors and enters the combustion chamber. So the AFPR has to be installed before the fuel rail not after.

 

[dsmgst1996]

So after the fuel enters the fuel rail where does it go? The fuel rail is the last place fuel goes before it hit's the injectors and enters the combustion chamber. So the AFPR has to be installed before the fuel rail not after.

Your fuel pump creates flow and then once the flow fills the fuel rail you have to create pressure witch is why the regulator is after the fuel rail to stop flow and increase pressure. Then unused fuel returns to the fuel tank . only a return less system as seen in Honda's dont use a return line and uses volts to fuel pump to control pressure.

 

[4gfun]

Sort of a subject change (not really since it is a placement question for a particular scenario) but since you are all here...

I am thinking about getting this same setup after reading what you and pitbull419 posted provided that it will work on my GVR4....a little concerned about engine to firewall dimensions and who knows what.

A few side questions here...

I am really trying to rule out a misfire at higher RPMs due to fuel starvation. I think that this setup would be a rather expensive way to go about that and I am tempted to just get a cheap liquid filled gauge and run it between the fuel filter and the fuel rail.

Would mounting a gauge there and temporarily duct taping it to my windshield be sufficient for diagnosing fuel issues? I am not confident that it would be 100% conclusive. I think it would only tell me whether or not my fuel pump is putting out sufficient pressure right?

If that is the case, and I go with this setup, could I run some fuel line temporarily and extend the gauge to my windshield via duct tape just to see what the fuel pressure is at WOT?

I think that this is overkill if I am trying to rule out fuel issues but not sure.

Use a hose, silly.

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But seriously, the fuel doesn't end at the rail. The excess fuel shed by the regulator is sent through a return line to the fuel tank.

 

[dsmgst1996]

your guage would have to be before regulator so you still need a adaptor or a t before the rail . yes it would work and tell you weather your getting the right pressure at wot .. classy move figuring out how to work duct tap in your fix !!!!!

 

[4gfun]

Lol, no class here!

Wouldn't I still be better off with that fancy pants setup when it comes to raw diagnosis though?

I don't want to miss out on anything by not viewing fuel pressure at the end of the rail.

If I don't check pressure at the end, I could still have a screwed up regulator and not see it right? Also possibly miss a few other potential problems no?

Just asking while all you brains are here!

your guage would have to be before regulator so you still need a adaptor or a t before the rail . yes it would work and tell you weather your getting the right pressure at wot .. classy move figuring out how to work duct tap in your fix !!!!!

 

[dsmgst1996]

Lol, no class here!

Wouldn't I still be better off with that fancy pants setup when it comes to raw diagnosis though?

I don't want to miss out on anything by not viewing fuel pressure at the end of the rail.

If I don't check pressure at the end, I could still have a screwed up regulator and not see it right? Also possibly miss a few other potential problems no?

Just asking while all you brains are here!

your line pressure and rail pressure will be the same before regulator you will miss nothing noticeable.

 

[4gfun]

Will it tell me if my fuel pressure regulator is bad if I locate it there?

I need to read up on how fuel pressure regulators work but wanted to ask you that before you disappeared into the Matrix.

Thanks

your line pressure and rail pressure will be the same before regulator you will miss nothing noticeable.

 

[project98dsm]

If you're looking for the diagnosis aspect (i.e. to keep an eye on whether or not your fuel pressure is rising 1:1 with your boost) just get a remote fuel sender for your fuel pressure gauge and mount it inside your car. The placement of your gauge needs to be before the regulator. Currently I'm running mine on top of my fuel filter with a M12x1.25 banjo bolt with a 1/8NPT fitting screwed into the top. Fuel pressure regulator will ALWAYS be AFTER the rail...no questions asked. If you mount the gauge on the regulator itself, it is STILL considered before the regulator because it is picking up pressure readings before the actual mechanism that controls the pressure within the regulator. It will work this way whether you have a fitting on the rail exit with a line going to the regulator mounted on the firewall, or if you have the regulator mounted directly onto the rail as I do.

 

[dsmgst1996]

Will it tell me if my fuel pressure regulator is bad if I locate it there?

I need to read up on how fuel pressure regulators work but wanted to ask you that before you disappeared into the Matrix.

Thanks

yes or if your fuel pump is weak also if you have not yet done it you might want to do fuel pump rewire.

 

[project98dsm]

Will it tell me if my fuel pressure regulator is bad if I locate it there?

I need to read up on how fuel pressure regulators work but wanted to ask you that before you disappeared into the Matrix.

Thanks

What do you mean if your regulator is bad? If it's bad it won't hold your fuel pressure with any consistency and/or it's being overran. If you mount it on or before the regulator, yes it will show this.

 

[4gfun]

Wow so many years of this and so much to learn ALWAYS, was thinking of going with something like this....

Tinted 100 PSI Fuel Pressure Gauge

I hear they may not be accurate though. Still, they are specifically for that intended purpose.

Have also used these just to check idle fuel pressure while being a cheapskate for years:

Pressure Gauges - Pressure & Vacuum Gauges & Instruments | MSCDirect.com

If you're looking for the diagnosis aspect (i.e. to keep an eye on whether or not your fuel pressure is rising 1:1 with your boost) just get a remote fuel sender for your fuel pressure gauge and mount it inside your car. The placement of your gauge needs to be before the regulator. Currently I'm running mine on top of my fuel filter with a M12x1.25 banjo bolt with a 1/8NPT fitting screwed into the top. Fuel pressure regulator will ALWAYS be AFTER the rail...no questions asked. If you mount the gauge on the regulator itself, it is STILL considered before the regulator because it is picking up pressure readings before the actual mechanism that controls the pressure within the regulator. It will work this way whether you have a fitting on the rail exit with a line going to the regulator mounted on the firewall, or if you have the regulator mounted directly onto the rail as I do.

Why do people post about the best place to mount the regulator being after the injectors? This is what is throwing me off.

Don't mind saving a ton of money and placing the regulator pre injectors, but trying to understand what people are implying by having the gauge after the injectors since there will be a pressure drop there.

Thanks

What do you mean if your regulator is bad? If it's bad it won't hold your fuel pressure with any consistency and/or it's being overran. If you mount it on or before the regulator, yes it will show this.

Thanks, yep I have done the fuel pump rewire already.

yes or if your fuel pump is weak also if you have not yet done it you might want to do fuel pump rewire.

 

[project98dsm]

Glowshift makes pretty decent gauges. I've used their mechanical boost gauge before but I can't really vouch for the quality of the electronic gauges/senders. Prosport is another brand you may want to look into that doesn't cost an arm and a leg. I will be changing my fuel setup soon and will be mounting my fuel pressure gauge inside. Have a glovebox setup I'll be trying to whip up for secondary gauges that I won't need to keep an eye on consistently but will be good to have