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-   -   A quick note on Fuel Pressure. (https://67-72chevytrucks.com/vboard/showthread.php?t=631987)

BR3W CITY 06-10-2014 05:01 PM

A quick note on Fuel Pressure.
 
Seems like about 60+% of the swaps that don't fire first-time have issues with fuel pressure. Thanks to LittleVictories for the fitting; I put together a few small videos on installing the Fuel Pressure gauge on the LS rails, and modding your engine cover to fit. Eliminating the FP guessing-game goes a long way.



dman1982 06-10-2014 06:12 PM

Re: A quick note on Fuel Pressure.
 
cool thread man, never seen ya before, i expected you to be some old fat balding guys lol

BR3W CITY 06-10-2014 06:17 PM

Re: A quick note on Fuel Pressure.
 
Quote:

Originally Posted by dman1982 (Post 6714885)
cool thread man, never seen ya before, i expected you to be some old fat balding guys lol

ahahaha naw man, I'm a fat 28 year old....with a shaved head. So your not THAT far off. Everyone thinks I'm an old man from talking to me :lol:
Between the people involved with my projects; 4 people all under 29, more than 40 years in the performance and racing industries.

dman1982 06-10-2014 06:19 PM

Re: A quick note on Fuel Pressure.
 
Ya man...and in your parents basement lol

KMC3420 06-10-2014 11:03 PM

Re: A quick note on Fuel Pressure.
 
Nice video and an easy enough mod. Should be a staple for all future LS swappers. Thanks br3w.

oldman3 06-11-2014 12:02 AM

Re: A quick note on Fuel Pressure.
 
Thanks for the video's, nice work...Jim

RocketChevy56 06-11-2014 08:37 AM

Re: A quick note on Fuel Pressure.
 
Add to LS FAQs Sticky!!!!

Nicely done Br3w!

Daaaanz67 06-11-2014 11:35 PM

Re: A quick note on Fuel Pressure.
 
I've been running one since day one of my swap that was two years ago this is a good idea my cover is different though nice work on yours. Not trying to hijack your thread. http://i1055.photobucket.com/albums/...C470A7DD43.jpg

Hart_Rod 06-12-2014 10:13 AM

Re: A quick note on Fuel Pressure.
 
Nice job J!

BR3W CITY 06-14-2014 12:33 AM

Re: A quick note on Fuel Pressure.
 
Quote:

Originally Posted by RocketChevy56 (Post 6715673)
Add to LS FAQs Sticky!!!!

I could live with that. :smoke:

kevmac 06-14-2014 03:17 AM

Re: A quick note on Fuel Pressure.
 
Yea thats nice! what about bleeding the system for returnless?

BR3W CITY 06-14-2014 03:57 AM

Re: A quick note on Fuel Pressure.
 
Quote:

Originally Posted by kevmac (Post 6720574)
Yea thats nice! what about bleeding the system for returnless?

Got me there....what about it? I've never bled a fuel rail, the pressure from the pump would force any air through the rail and *burp* it during startup. The only time I've ever had an issue with air in fuel lines was from the pump pickup being in the wrong point, or a leak somewhere causing air infiltration.

Made me google it too, couldn't find any commonplace issues with air in the line, nor anything about bleeding the sytem (aside from tapping the schroeder valve to check pressure). Maybe someone else can chime in here.

Blackpony 06-14-2014 10:19 PM

Re: A quick note on Fuel Pressure.
 
I had an experience once with a 2004 vette. Just built a new 414 stroker and installed it. Fired the car up and the whole passenger bank was not firing. Chased my tail on that one checking everything. Went to pull the fuel rail off and psssss huge burst of air blows out on the passenger side. Hit the key to make sure the rail wasnt clogged, put it back together and it fired right up ran like a champ. Ended up woth 559/525 na to the tires on that car. Craziest thing I have ever seen!!!

BR3W CITY 06-16-2014 01:36 AM

Re: A quick note on Fuel Pressure.
 
Quote:

Originally Posted by Blackpony (Post 6721356)
I had an experience once with a 2004 vette. Just built a new 414 stroker and installed it. Fired the car up and the whole passenger bank was not firing. Chased my tail on that one checking everything. Went to pull the fuel rail off and psssss huge burst of air blows out on the passenger side. Hit the key to make sure the rail wasnt clogged, put it back together and it fired right up ran like a champ. Ended up woth 559/525 na to the tires on that car. Craziest thing I have ever seen!!!

Were you able to tell WHERE the air got trapped? Like, if the truck was OFF, I could see how the dead-headed rail could get air trapped in the far/high end, and then the pump would be trying to compress that air. But with the injectors firing, how the hell does the air avoid the constant way-out?

One yall engineers in here needs to explain how the fluid can do this to me, cuz my brain refuses to see how this would happen.

kevmac 06-16-2014 09:30 AM

Re: A quick note on Fuel Pressure.
 
I just upgraded my 67 camaro to a fast 92/92 setup yesterday. Initial fuel pressure was 40ish until I cracked the aft cap on the billet rails and boom, shot up to 50 plus. I guess the question is before I get the 5.3 going in the c10 is where all do the air bubbles hide. Gonna try some more to bleed out the camaro today, my c10 still a month or so from start up but the same principle applies. Air compresses and liquids don't, lest not much. For those running return style shouldn't be a prob I'd think.

BR3W CITY 06-18-2014 01:27 AM

Re: A quick note on Fuel Pressure.
 
This whole "air in the fuel rail" thing is just fishy to me. I've been around these things enough that I feel like if it were common (or even commonly discussed), I would have heard/read/written/seen the issue...which up until this thread, I really never have.

Yes, air can get into the fuel system from the pump end, or from a damaged line getting air into the system; but that air would travel (by weight and force) to the high point in the system, which would be the rail. When the air reaches the rail, the force of the fuel behind it would try to compress the air assuming the engine is OFF and all the injectors are closed, creating a sealed situation in which the air had nowhere to go. The second the engine starts, that pressurized air would be forced out the injector nozzle.

Usually, when air DOES get into the system, the motor might sputter or cough for a second and go slightly lean, since the air was being expelled with the fuel into the chamber. There is no GM procedure for bleeding air from the system, its a self remedying problem.

If this wasn't the case, imagine this scenario; your driving home, tank on E. You take a sharp corner to make a yellow, the pickup loses fuel and sucks air/aerated fuel into the lines....which would mean that you had introduced air into the system, and now needed to bleed the air back out. It would be unacceptable from an engineering standpoint.

My .04 cents

DjS71 06-18-2014 08:14 AM

Re: A quick note on Fuel Pressure.
 
Great idea. :metal: Added these to my parts box for whenever I get around to the swap, nice inexpensive peace of mind/ quick diag add-on.

Hart_Rod 06-18-2014 08:26 AM

Re: A quick note on Fuel Pressure.
 
Quote:

Originally Posted by BR3W CITY (Post 6725792)
This whole "air in the fuel rail" thing is just fishy to me. I've been around these things enough that I feel like if it were common (or even commonly discussed), I would have heard/read/written/seen the issue...which up until this thread, I really never have.

Yes, air can get into the fuel system from the pump end, or from a damaged line getting air into the system; but that air would travel (by weight and force) to the high point in the system, which would be the rail. When the air reaches the rail, the force of the fuel behind it would try to compress the air assuming the engine is OFF and all the injectors are closed, creating a sealed situation in which the air had nowhere to go. The second the engine starts, that pressurized air would be forced out the injector nozzle.

Usually, when air DOES get into the system, the motor might sputter or cough for a second and go slightly lean, since the air was being expelled with the fuel into the chamber. There is no GM procedure for bleeding air from the system, its a self remedying problem.

If this wasn't the case, imagine this scenario; your driving home, tank on E. You take a sharp corner to make a yellow, the pickup loses fuel and sucks air/aerated fuel into the lines....which would mean that you had introduced air into the system, and now needed to bleed the air back out. It would be unacceptable from an engineering standpoint.

My .04 cents

I agree. The only way I see air getting "stuck" in the system is if you had some injectors that were stuck closed.

c10seconds 06-18-2014 12:17 PM

Re: A quick note on Fuel Pressure.
 
Nice walk through Vid man. Thanks for the shout out

Andy4639 06-22-2014 07:20 PM

Re: A quick note on Fuel Pressure.
 
Hawk's put mine on the passenger side of the fuel rail. For what reason I'm not sure other than if it had a obstruction in that side fuel rail it would be noticed. I guess to you know you have complete fuel pressure to the whole system with it mounted on the passenger side. ;):chevy:

http://i1233.photobucket.com/albums/...psf6702360.jpg

Blackpony 06-22-2014 08:49 PM

Re: A quick note on Fuel Pressure.
 
Quote:

Originally Posted by BR3W CITY (Post 6722741)
Were you able to tell WHERE the air got trapped? Like, if the truck was OFF, I could see how the dead-headed rail could get air trapped in the far/high end, and then the pump would be trying to compress that air. But with the injectors firing, how the hell does the air avoid the constant way-out?

One yall engineers in here needs to explain how the fluid can do this to me, cuz my brain refuses to see how this would happen.

It was on a corvette fuel rail which is a dead head and the air was trapped on the passenger side. I had 3 other people there at the time. We racked our brains trying to figure out why the entire passenger side bank was not firing. Craziest thing i have ever seen. I would have thought that the injectors would just fire the air through the injectors but that wasn't happening.

DjS71 06-25-2014 08:15 AM

Re: A quick note on Fuel Pressure.
 
Hawk's link - Andy

Wonder if it depresses the schrader valve or if you remove the core... Price is right.

littlevictories 06-25-2014 11:39 AM

Re: A quick note on Fuel Pressure.
 
that is a pretty slick fix for guys with stock fuel rails

pbr 06-25-2014 04:39 PM

Re: A quick note on Fuel Pressure.
 
I have similar to what andy has it an aeroquip 2242-2-4s fitting and a summit gauge. I did have to remove the schrader valve.


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