Air/Fuel ratio
Thread Starter
Burning Brakes
Joined: Sep 2002
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From: Misawa
St. Jude Donor '08
Air/Fuel ratio
Can anyone tell me a little more about this one. I bought the after market fuel pressure regulator and I have the gauge/adjuster. I was also doing some research on what the best ratio's are. According to this link http://www.vetteguru.com/mods/howto/ the best ratio for performance is 13-1 (12-6-1) and for daily driving is 15-1. Well, my fuel regulator is in psi. How do I know where to set that for track and daily driving. I've done mods to it so I'm sure the air intake is quite different. How would I figure this out. Even if someone could tell me were the set there for these occasions help me out till I get a good explaination this. Thanks
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From: Sunshine State
Originally Posted by vetracn98
Can anyone tell me a little more about this one. I bought the after market fuel pressure regulator and I have the gauge/adjuster. I was also doing some research on what the best ratio's are. According to this link http://www.vetteguru.com/mods/howto/ the best ratio for performance is 13-1 (12-6-1) and for daily driving is 15-1. Well, my fuel regulator is in psi. How do I know where to set that for track and daily driving. I've done mods to it so I'm sure the air intake is quite different. How would I figure this out. Even if someone could tell me were the set there for these occasions help me out till I get a good explaination this. Thanks
Bob
Last edited by Korreck; Apr 26, 2005 at 08:31 PM.
Thread Starter
Burning Brakes
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From: Misawa
St. Jude Donor '08
Originally Posted by Korreck
I think you're talking about YOUR fuel pressure regulator. That will not tell you your fuel/air mixture.
Bob
Bob
Well yes that is exactly what I am talking about. How can I figure out what to tune it to to get a 13-1 and 15-1. For instance 52psi on my fule pressure regulator will give me 13-1 and 48 will give me 15-1. This is what I am trying to figure out. Or does this not have anything to do with me getting these ratio's
Safety Car
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From: Sunshine State
Originally Posted by vetracn98
Well yes that is exactly what I am talking about. How can I figure out what to tune it to to get a 13-1 and 15-1. For instance 52psi on my fule pressure regulator will give me 13-1 and 48 will give me 15-1. This is what I am trying to figure out. Or does this not have anything to do with me getting these ratio's
Bob
Thread Starter
Burning Brakes
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From: Misawa
St. Jude Donor '08
Originally Posted by Korreck
That has nothing to do with it. It simply measures and allows you to set the fuel pressure. You'll need to tune to get your air/fuel changed. Suggest you find a good tuner.
Bob
Bob
Hmm well if adjust it does nothing for me performance wise.....why the hell did I buy it
Team Owner
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From: S.W. Ohio. . . . . . NRA Life Member
It simply measures and allows you to set the fuel pressure. You'll need to tune to get your air/fuel changed. Suggest you find a good tuner.
A/F ratio changes are accomplished by altering the programming in your engine computer (PCM).
Safety Car
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From: Sunshine State
Originally Posted by vetracn98
Hmm well if adjust it does nothing for me performance wise.....why the hell did I buy it
A fuel pressure regulator is used usually if you have a highly modified carburated engine. On my 502 stroker with a large Holley carb I used a pressure regulator to maintain 30PSI.
I don't know why you bought yours.
Bob
Thread Starter
Burning Brakes
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From: Misawa
St. Jude Donor '08
Originally Posted by Mike Mercury
A/F ratio changes are accomplished by altering the programming in your engine computer (PCM).So why would anyone want to get an adjustable fuel pressure regulator. I guess I should have done more research on this one. Since this adjustment can only be done in a pcm......then I take you just have to pick one or the other...always rich or lean. Right?
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Thread Starter
Burning Brakes
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From: Misawa
St. Jude Donor '08
Originally Posted by Korreck
I
I don't know why you bought yours.
Bob
I don't know why you bought yours.
Bob
ROFL..........looks like i don't know either. I have had my pcm tuned all ready I just don't know what the set it at. I guess I can do some digging back at WCC and find out who they use and then contact them. Yes you can't find a tuner here period!!!
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From: Sunshine State
Originally Posted by vetracn98
So why would anyone want to get an adjustable fuel pressure regulator. I guess I should have done more research on this one. Since this adjustment can only be done in a pcm......then I take you just have to pick one or the other...always rich or lean. Right?
Safety Car
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From: Sunshine State
Originally Posted by vetracn98
ROFL..........looks like i don't know either. I have had my pcm tuned all ready I just don't know what the set it at. I guess I can do some digging back at WCC and find out who they use and then contact them. Yes you can't find a tuner here period!!!
Thread Starter
Burning Brakes
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From: Misawa
St. Jude Donor '08
Originally Posted by Korreck
There are good tuners and bad tuners. If you don't mind spending another $500 I can put you in touch with my tuner. But what you have may be OK. You'll have to find out. PM me if you need more help.
Cool ty. maybe i should start another thread and see if anyone else got this mod and why then? well since I do have it, where do think I should have my psi set? Does it make if a difference with have it bone stock or with mods done to it, or should I just check everyonce in awhile and make sure it hasn't changed.
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From: Sunshine State
Originally Posted by vetracn98
Cool ty. maybe i should start another thread and see if anyone else got this mod and why then? well since I do have it, where do think I should have my psi set? Does it make if a difference with have it bone stock or with mods done to it, or should I just check everyonce in awhile and make sure it hasn't changed.
Bob
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From: Hobart, WI
The PCM controls your A/F ratio in closed loop to be 14.7. That is fixed except in open loop which is WOT. By adjusting PE you can set your WOT A/F to be what you like. BTW 13.5 is leaner than most anyone would tune for. Just to make sure, remember it is parts air to parts fuel so 12 is richer than 13.