NAIOA.comNAIOA.comNAIOA.com
 Create an Account
 

  
NAIOA Impala Forums :: View topic - fuel pressure regulator mod??
GarageGarage    1/4 Mile Table1/4 Mile Table    Forum FAQForum FAQ    SearchSearch    UsergroupsUsergroups   MedalsMedals
MemberlistMemberlist   ProfileProfile    Watched TopicsWatched Topics    Log in to check your private messagesLog in to check your private messages    Log inLog in 

fuel pressure regulator mod??
Goto page 1, 2, 3  Next
 
Post new topic   Reply to topic    NAIOA Impala Forums Forum Index -> 2000-2005 Engine, Exhaust and Transmission
View previous topic :: View next topic  
Author Message
james04Ls
Newbie
Newbie


Joined: May 09, 2010
Posts: 36
Posts per day: 0.01
Location: zurich, ON CANADA

2004 Chevrolet Impala


PostPosted: Thu Apr 19, 2012 6:22 pm    Post subject:  fuel pressure regulator mod?? Reply with quote

has anyone ever disconnected the vacuum line on the fuel pressure regulator??
I was screwing around at school today, im attending fanshawe college for my apprentiship, we were doing a fuel pressure lab. When you pull the vacuum line off the regulator, the fuel pressure spikes to max pressure 55psi. Now the pump puts out 55 psi at wide open throttle when there is no vacuum, but at idle the pressure drops to 42psi. With the regulator disabled, the fuel rail gets max pressure all the time. I tried it out today and the injectors still stay open the same amount of time so the cylinders get more fuel. This has no affect on top end power but it helps out a bit more on mid range acceleration.

Try it out and let me know what you think ? any thaughts or feedback??
Back to top
View user's profile Send private message
outonthetiles
Member Level
Member Level
Bronze Contributor (Amount: 1) Bronze Contributor


Joined: Jul 12, 2006
Posts: 1113
Posts per day: 0.27
Location: Ilion, NY

2000 Chevrolet Impala
1990 Volvo 240
2000 Buick Regal


PostPosted: Thu Apr 19, 2012 6:28 pm    Post subject:   Reply with quote

Probably not a good idea.. A FPR is there for a reason. Look at all of the high horsepower gtp builds, FPR is still there.

_________________

2000 Impala LS: Getrag 284 Swapped
Back to top
View user's profile Send private message
james04Ls
Newbie
Newbie


Joined: May 09, 2010
Posts: 36
Posts per day: 0.01
Location: zurich, ON CANADA

2004 Chevrolet Impala


PostPosted: Thu Apr 19, 2012 7:04 pm    Post subject:   Reply with quote

isn't the purpose of the fuel pressure regulator to control the pressure differences needed at different rpms, at WOT the pressure is still 55 PSI im just changing the lower rpm pressure. Because the pcm still hold the injector open for 3 miliseconds if there is more pressure there will be more fuel entering the cylinders. I dont think the regulator stops the pressures form getting too high. i know its there for a reason, it would help lower pressures at idle when high pressure isnt needed
Back to top
View user's profile Send private message
grimsin
Member Level
Member Level


Joined: Oct 27, 2009
Posts: 1179
Posts per day: 0.4
Location: Port Stanley ON

2005 Chevrolet Impala


PostPosted: Thu Apr 19, 2012 7:10 pm    Post subject:   Reply with quote

if the injectors are controlling how much fuel is going in then 1000psi isnt gonna make a difference, my 2 Cents

_________________

Mods:4'' HAI\L67 HVTB\HV3\ER Rockers\WP underdrive pulley\Headers\cat delete\91 octane overkill incar tune.
3.69 gears soon!!
Back to top
View user's profile Send private message
outonthetiles
Member Level
Member Level
Bronze Contributor (Amount: 1) Bronze Contributor


Joined: Jul 12, 2006
Posts: 1113
Posts per day: 0.27
Location: Ilion, NY

2000 Chevrolet Impala
1990 Volvo 240
2000 Buick Regal


PostPosted: Thu Apr 19, 2012 7:17 pm    Post subject:   Reply with quote

It probably will get a little more fuel, but that's not helping you out at all. You want a correct air/fuel ratio. Without introducing more air, which you're not, you're burning more fuel for no reason. The PCM controlls how much fuel the cylinders get based on the input of many sensors. If they needed more fuel, it would give them more fuel. You are essentially tricking the car into changing the air/fuel ratio and I think that could be risky.

_________________

2000 Impala LS: Getrag 284 Swapped
Back to top
View user's profile Send private message
james04Ls
Newbie
Newbie


Joined: May 09, 2010
Posts: 36
Posts per day: 0.01
Location: zurich, ON CANADA

2004 Chevrolet Impala


PostPosted: Thu Apr 19, 2012 7:29 pm    Post subject:   Reply with quote

the pcm just controls how long the injectors are open for, if there is more pressure and the injectors are open for the same amount of time then there will be more fuel in the cylinder.

you are right,, i am esentially changing the air/fuel mix, at idle the engine wants stoichiometric ratio for complete combustion but at high engine load it will ritchen the mixture for more power, im just giving it a richer mix at lower rpm, which makes harder on fuel. You wouldent want to run it like that all the time, but if you went to the track for the day it would be an easy way to pick up some accel on takeoff , because the injectors get more pressure all the time, if you combined this will a fuel pump rewire, and voltage booster you could get a little more fuel pressure??

what risks do you think there would be running a rich mixture all the time?
Back to top
View user's profile Send private message
outonthetiles
Member Level
Member Level
Bronze Contributor (Amount: 1) Bronze Contributor


Joined: Jul 12, 2006
Posts: 1113
Posts per day: 0.27
Location: Ilion, NY

2000 Chevrolet Impala
1990 Volvo 240
2000 Buick Regal


PostPosted: Thu Apr 19, 2012 7:42 pm    Post subject:   Reply with quote

Unburnt fuel.. carbon buildup.. for no gains.

If you're feeling gains from that, its all in your head.

But its not my car, so do what you want. But don't recommend this to anyone please. Its really a useless mod. Your FPR is not restricting the flow of gas, you will get gas when you need it, that's how it operates.

Besides, the PCM richens up the fuel mixture under WOT to prevent detonation, not to give you more power.

_________________

2000 Impala LS: Getrag 284 Swapped
Back to top
View user's profile Send private message
nightryder
Master Level
Master Level
Silver Contributor (Amount: 1) Silver Contributor


Joined: Oct 18, 2006
Posts: 3256
Posts per day: 0.8
Location: Lockport NY

2001 Chevrolet Impala
2005 Subaru Impreza


PostPosted: Thu Apr 19, 2012 8:02 pm    Post subject:   Reply with quote

Bad idea.

Your IFR will be all kinds of Eff'd with a higher fuel pressure, which means you will run rich. The PCM can control that while in closed loop, but when it goes into open loop at WOT it's going to run stupid rich.

Leaner AFR = more power BTW. (specifically 14.7 AFR)

_________________
Back to top
View user's profile Send private message AIM Address
james04Ls
Newbie
Newbie


Joined: May 09, 2010
Posts: 36
Posts per day: 0.01
Location: zurich, ON CANADA

2004 Chevrolet Impala


PostPosted: Thu Apr 19, 2012 9:28 pm    Post subject:   Reply with quote

At WOT the fuel pump puts out 55PSI anyway, so its not getting any more fuel at WOT than it is with the regulator on, the engine gets more fuel at low rpm with the regulator disconnected because normally the regulator gets vacuum and lowers pressure
at WOT don't you want a richer mixture??
the only thing a lean burn is good for is fuel mileage, thats why all the new economy cars run an air fuel ratio of like 40:1
Back to top
View user's profile Send private message
grimsin
Member Level
Member Level


Joined: Oct 27, 2009
Posts: 1179
Posts per day: 0.4
Location: Port Stanley ON

2005 Chevrolet Impala


PostPosted: Fri Apr 20, 2012 8:52 am    Post subject:   Reply with quote

if it made power, people would of been doing it years ago, your gonna end up breaking something for maybe 1-2hp just cause you butt dyno says more powa Laughing
want more fuel going in start some real modz Wink

_________________

Mods:4'' HAI\L67 HVTB\HV3\ER Rockers\WP underdrive pulley\Headers\cat delete\91 octane overkill incar tune.
3.69 gears soon!!
Back to top
View user's profile Send private message
outonthetiles
Member Level
Member Level
Bronze Contributor (Amount: 1) Bronze Contributor


Joined: Jul 12, 2006
Posts: 1113
Posts per day: 0.27
Location: Ilion, NY

2000 Chevrolet Impala
1990 Volvo 240
2000 Buick Regal


PostPosted: Fri Apr 20, 2012 10:17 am    Post subject:   Reply with quote

As I said, you want a richer mixture at WOT to prevent detonation, not to make power. There's a "sweet spot" so to speak, and when you step off either side you lose power.

End of discussion, man. Run it on your car if you want, but don't recommend it to others because it is a dumb thing to do.

Looking for a free butt dyno mod? Gut your intake box.

_________________

2000 Impala LS: Getrag 284 Swapped
Back to top
View user's profile Send private message
james04Ls
Newbie
Newbie


Joined: May 09, 2010
Posts: 36
Posts per day: 0.01
Location: zurich, ON CANADA

2004 Chevrolet Impala


PostPosted: Fri Apr 20, 2012 10:24 am    Post subject:   Reply with quote

it seems like i pissed u off talking about this, im sorry if i did because that wasn't my intention, just trying to crate discussion about something that intrigued me, thanks for all the feedback and suggestions!
Back to top
View user's profile Send private message
nightryder
Master Level
Master Level
Silver Contributor (Amount: 1) Silver Contributor


Joined: Oct 18, 2006
Posts: 3256
Posts per day: 0.8
Location: Lockport NY

2001 Chevrolet Impala
2005 Subaru Impreza


PostPosted: Fri Apr 20, 2012 11:06 am    Post subject:   Reply with quote

james04Ls wrote:
At WOT the fuel pump puts out 55PSI anyway, so its not getting any more fuel at WOT than it is with the regulator on


False. The fuel pressure is constant in a 1 BAR FPR

Quote:
at WOT don't you want a richer mixture??


The ONLY reason you want a rich mixture is to prevent detonation under WOT, as was mentioned earlier.

Quote:
the only thing a lean burn is good for is fuel mileage, thats why all the new economy cars run an air fuel ratio of like 40:1


HA! I love this forum Laughing It's pretty obvious that you don't know what you're talking about.

_________________
Back to top
View user's profile Send private message AIM Address
james04Ls
Newbie
Newbie


Joined: May 09, 2010
Posts: 36
Posts per day: 0.01
Location: zurich, ON CANADA

2004 Chevrolet Impala


PostPosted: Fri Apr 20, 2012 11:20 am    Post subject:   Reply with quote

put a fuel pressure guage on the rail at idle, the guage reads about 42 psi. Crack the throttle wide open for a second, the pressure spikes to 55 psi then drops down, try it your self. then disconnect the vaccum line off the FPR the pressure jumps to 55 PSI and stays there

Injector pulse width is controlled by the PCM depending on engine load, if the knock sensor senses detonatin or pre-ignition it either advances or retards the timming to counter act, it doesnt adjust injector pulse width


to prevent detonation you would retard the timming, not richen the mixture
Back to top
View user's profile Send private message
outonthetiles
Member Level
Member Level
Bronze Contributor (Amount: 1) Bronze Contributor


Joined: Jul 12, 2006
Posts: 1113
Posts per day: 0.27
Location: Ilion, NY

2000 Chevrolet Impala
1990 Volvo 240
2000 Buick Regal


PostPosted: Fri Apr 20, 2012 11:22 am    Post subject:   Reply with quote

You did piss me off.

We're telling you why you're idea is dumb. And you insist that it works, contrary to the facts we're telling you.


To anyone reading this thread: leave you're FPR alone.

_________________

2000 Impala LS: Getrag 284 Swapped
Back to top
View user's profile Send private message
Display posts from previous:   
Post new topic   Reply to topic    NAIOA Impala Forums Forum Index -> 2000-2005 Engine, Exhaust and Transmission All times are GMT - 4 Hours
Goto page 1, 2, 3  Next
Page 1 of 3

 
Jump to:  
You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot vote in polls in this forum

Powered by phpBB © 2001, 2005 phpBB Group
Forums ©
All logos and trademarks in this site are property of their respective owner. Comments and posts are property of the poster. All other content is © 2008 by the NAIOA.


Use of this site constitutes agreement with the NAIOA Terms of Service (TOS)


PHP-Nuke Copyright © 2005 by Francisco Burzi. This is free software, and you may redistribute it under the GPL. PHP-Nuke comes with absolutely no warranty, for details, see the license.
Server Local Time: November 17, 2017, 3:23:42 pm
Page Generation: 0.14 Seconds ( SQL 45:144 in 0.01 Seconds )