Setting AFPR by O2 and BLM values
Thread Starter
Banned
Joined: May 2001
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From: Detroit Suburbia, MI USA
Setting AFPR by O2 and BLM values
I am going to get a AFPR within the next week or so. I have access to a Snap On scanner and would like to get an idea where to set the pressure in relation to O2 values and BLM. I know I want to have the O2 around .850 give or take. I also know that the BLM, in a perfect setting, would be at 128 at all times. So I guess my question is how can I optimize the AFPR for part-throttle as well as WOT? I will be messing with it at the track, also.
TIA for the help. Always seems I came to the right place
------------------
Mike L.
It ain't pretty.......
1987 IROC Z TPI 350 A4 3.27 Borg-Warner.
Mods: 2300-2500 Stall Converter, Shift Kit(GM parts), TPI Specialties Stage 3 PROM, Modified Airbox w/ K&N's, homemade cold air, Relocated MAT sensor, Gutted MAF, 160* thermostat, MSD 6A, Accel 8mm Wires, bypassed TB coolant, Flowmaster 3 chamber single 3" in/out muffler, 3" MAC mandrel intermediate, custom dual !cat Y-pipe. airfoil, ported plenum. !smog
http://www.MichaelLasiuta.home.att.net
**BOYCOTT LAPEER DRAGWAY**
TIA for the help. Always seems I came to the right place
------------------
Mike L.
It ain't pretty.......
1987 IROC Z TPI 350 A4 3.27 Borg-Warner.
Mods: 2300-2500 Stall Converter, Shift Kit(GM parts), TPI Specialties Stage 3 PROM, Modified Airbox w/ K&N's, homemade cold air, Relocated MAT sensor, Gutted MAF, 160* thermostat, MSD 6A, Accel 8mm Wires, bypassed TB coolant, Flowmaster 3 chamber single 3" in/out muffler, 3" MAC mandrel intermediate, custom dual !cat Y-pipe. airfoil, ported plenum. !smog
http://www.MichaelLasiuta.home.att.net
**BOYCOTT LAPEER DRAGWAY**
TGO Supporter
Joined: Jul 1999
Posts: 10,907
Likes: 5
From: The Bone Yard
Car: Death Mobile
Engine: 666 c.i.
<font face="Verdana, Arial" size="2">Originally posted by IROC5.7TPI:
I am going to get a AFPR within the next week or so. I have access to a Snap On scanner and would like to get an idea where to set the pressure in relation to O2 values and BLM. I know I want to have the O2 around .850 give or take. I also know that the BLM, in a perfect setting, would be at 128 at all times. So I guess my question is how can I optimize the AFPR for part-throttle as well as WOT? I will be messing with it at the track, also.
TIA for the help. Always seems I came to the right place
</font>
I am going to get a AFPR within the next week or so. I have access to a Snap On scanner and would like to get an idea where to set the pressure in relation to O2 values and BLM. I know I want to have the O2 around .850 give or take. I also know that the BLM, in a perfect setting, would be at 128 at all times. So I guess my question is how can I optimize the AFPR for part-throttle as well as WOT? I will be messing with it at the track, also.
TIA for the help. Always seems I came to the right place
</font>
Supreme Member
Joined: Sep 1999
Posts: 3,197
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From: Manassas VA
Car: 04 GTO
Engine: LS1
Transmission: M12 T56
You definitely can't get both BLMs and WOT dialed in with an AFPR unless the stock PE enrichment tables are perfect for when your FPR is set to make the VE tables perfect. Very unlikely. Myself, i bumped FP way up, then took out the fuel i needed to get the BLMs back close.....and now i've increased my PE fuel about the same amount that i moved the injector constant and it seems to be close.
...ed
...ed
TGO Supporter
Joined: Jul 1999
Posts: 10,907
Likes: 5
From: The Bone Yard
Car: Death Mobile
Engine: 666 c.i.
Actually that raises another point that most people overlook. While increased fuel pressure does promote a better spray pattern, with the stock prom and minimal mods, the engine already has too much fuel.
GM purposely made the stock eprom too rich, primarily for "warranty reasons". Increasing fuel pressure (by itself) is generally the last thing you need on most "basically" stock engines. I found that even with my AFPR set low (under 40 psi), I was STILL too rich with my stock eprom and it required fuel to be pulled to get the mixture right. It was at this point, that I got into Prom Burning because I saw the conflict, even with the AFPR at a low setting.
GM purposely made the stock eprom too rich, primarily for "warranty reasons". Increasing fuel pressure (by itself) is generally the last thing you need on most "basically" stock engines. I found that even with my AFPR set low (under 40 psi), I was STILL too rich with my stock eprom and it required fuel to be pulled to get the mixture right. It was at this point, that I got into Prom Burning because I saw the conflict, even with the AFPR at a low setting.
Thread Starter
Banned
Joined: May 2001
Posts: 294
Likes: 0
From: Detroit Suburbia, MI USA
Look at my mods. Is it too soon to get the AFPR? If anything I want to take out fuel. Guess I gotta run a scan and see.
Thanks again for the advice.
------------------
Mike L.
It ain't pretty.......
1987 IROC Z TPI 350 A4 3.27 Borg-Warner.
Mods: 2300-2500 Stall Converter, Shift Kit(GM parts), TPI Specialties Stage 3 PROM, Modified Airbox w/ K&N's, homemade cold air, Relocated MAT sensor, Gutted MAF, 160* thermostat, MSD 6A, Accel 8mm Wires, bypassed TB coolant, Flowmaster 3 chamber single 3" in/out muffler, 3" MAC mandrel intermediate, custom dual !cat Y-pipe. airfoil, ported plenum. !smog
http://www.MichaelLasiuta.home.att.net
**BOYCOTT LAPEER DRAGWAY**
Thanks again for the advice.
------------------
Mike L.
It ain't pretty.......
1987 IROC Z TPI 350 A4 3.27 Borg-Warner.
Mods: 2300-2500 Stall Converter, Shift Kit(GM parts), TPI Specialties Stage 3 PROM, Modified Airbox w/ K&N's, homemade cold air, Relocated MAT sensor, Gutted MAF, 160* thermostat, MSD 6A, Accel 8mm Wires, bypassed TB coolant, Flowmaster 3 chamber single 3" in/out muffler, 3" MAC mandrel intermediate, custom dual !cat Y-pipe. airfoil, ported plenum. !smog
http://www.MichaelLasiuta.home.att.net
**BOYCOTT LAPEER DRAGWAY**
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