Help on AFPR Settings
Thread Starter
Instructor
Joined: Nov 2001
Posts: 102
Likes: 0
From: Olympia Wa
Help on AFPR Settings
I just aquired a used Accell AFPR, There was no documntation that came with it, I just want to know what would be a good starting point for the pressure, and what is everyone else is running with light mods on an early L98. My sig has most of the mods done to the car allready........ any advise would be helpfull..............
TIA
Cruz :)
TIA
Cruz :)
Melting Slicks
Joined: Jun 2001
Posts: 2,525
Likes: 1
From: Sarasota, FL
Re: Help on AFPR Settings (Cruzin I-5)
Mine is at 39lbs, I spent a whole night at the dragstrip trying different settings. Keep in mind tho, I am at 4800' and rarely if ever go below that, usually up.
Team Owner
Joined: Dec 2000
Posts: 90,675
Likes: 304
From: SE NY
Cruise-In II Veteran
Re: Help on AFPR Settings (Cruzin I-5)
First put a gauge on the Schraeder valve (I realy like the ACCEL from JEG's) and record the stock setting.
With this as baseline for the AFPR go to the strip and use trap speed to dial in the optimum setting.
With a few more air flow mods I run 48psi and get about 12.6:1 air/fuel at WOT (from dyno pulls). This shows up as about 910-920mV on a scan tool.
You are running 24lb injectors vs my 22lb units and so are pushing about 9% more fuel at a given pressure setting (and this assumes that both injectors are rated at the same pressure, i.e. 43.5psi). Flow goes as the Square Root of pressure change so about 38-40psi might work well for you. BTW, you're L98 realy don't need 24lb injectors till it's buiding over 350hp.
With this as baseline for the AFPR go to the strip and use trap speed to dial in the optimum setting.
With a few more air flow mods I run 48psi and get about 12.6:1 air/fuel at WOT (from dyno pulls). This shows up as about 910-920mV on a scan tool.
You are running 24lb injectors vs my 22lb units and so are pushing about 9% more fuel at a given pressure setting (and this assumes that both injectors are rated at the same pressure, i.e. 43.5psi). Flow goes as the Square Root of pressure change so about 38-40psi might work well for you. BTW, you're L98 realy don't need 24lb injectors till it's buiding over 350hp.
Thread Starter
Instructor
Joined: Nov 2001
Posts: 102
Likes: 0
From: Olympia Wa
Re: Help on AFPR Settings (Cruzin I-5)
the 24 # er's are what came with the 85 L98 stock........late 86 i believe they went to the 22# injectors...........and 19# on the f-bodys.........
being here in seattle the tracks wont open untill the end of april, so I was just looking for a quick fix just to get it on the car......
:D
being here in seattle the tracks wont open untill the end of april, so I was just looking for a quick fix just to get it on the car......
:D
Pro
Joined: Dec 2001
Posts: 715
Likes: 0
From: NYC NY
Re: Help on AFPR Settings (Cruzin I-5)
Just try out different settings. Most people I think run mid to high 40's with L98's though with 24lb. injectors you might want to start out lower. Drive the car around for a few minutes at the new setting and then take it somewhere where you can open her up.
I have run mine as low as 41psi and gotten good low end throttle response, but the motor would really bail at higher rpms. Running at 48psi I got good low response and it pulled hard to 6300. Thats with a miniram though.
Trial by feel, or at the track, or on a dyno is really the only way to get it right.
I have run mine as low as 41psi and gotten good low end throttle response, but the motor would really bail at higher rpms. Running at 48psi I got good low response and it pulled hard to 6300. Thats with a miniram though.
Trial by feel, or at the track, or on a dyno is really the only way to get it right.
Drifting
Joined: Aug 2000
Posts: 1,521
Likes: 0
From: West Islip New York
Re: Help on AFPR Settings (65Z01)
First put a gauge on the Schraeder valve (I realy like the ACCEL from JEG's) and record the stock setting.
