BPW and SA Calculations ($32B)
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Joined: Aug 2003
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From: Nowthen MN
BPW and SA Calculations ($32B)
I am at a loss. The people in this forum have been a huge amount of help in the past and I hope someone can throw me a line on this one.
When BPW Calibration method is unchecked in $32B, what factors affect BPW and SA (in closed loop and in open loop)? How does the Spark Correction - LV8/2 vs Coolant temp affect total advance?
I have an extremely rich idle condition that I have tried to chase all day. I have been chasing SA, MAF, and BPW to no avail. My eyes are burning from the fumes.
One method suggests having the BPW Calibration flag checked and to modify the BPW vs. Load table. I had my constants all the way down to .5 and could not get BPW low enough.
Another method says to increase the injector constants. I changed single and double fire incrementally to 40 with no luck.
Another method I found says to uncheck the BPW Calibration flag and modify the MAF tables where the Grams / Sec is too rich and move the value down (thinking there is less air flow so it cuts fuel). This gave me some of the best results but still no where near where it needs to be. I was able to cut a considerable amount of SA out. I shouldn't need to run 32* of advance at idle should I?
What am I missing here?
Please don't suggest changing to 6E as this is a 4+3 car and I refuse to lose O/D capability.
When BPW Calibration method is unchecked in $32B, what factors affect BPW and SA (in closed loop and in open loop)? How does the Spark Correction - LV8/2 vs Coolant temp affect total advance?
I have an extremely rich idle condition that I have tried to chase all day. I have been chasing SA, MAF, and BPW to no avail. My eyes are burning from the fumes.
One method suggests having the BPW Calibration flag checked and to modify the BPW vs. Load table. I had my constants all the way down to .5 and could not get BPW low enough.
Another method says to increase the injector constants. I changed single and double fire incrementally to 40 with no luck.
Another method I found says to uncheck the BPW Calibration flag and modify the MAF tables where the Grams / Sec is too rich and move the value down (thinking there is less air flow so it cuts fuel). This gave me some of the best results but still no where near where it needs to be. I was able to cut a considerable amount of SA out. I shouldn't need to run 32* of advance at idle should I?
What am I missing here?
Please don't suggest changing to 6E as this is a 4+3 car and I refuse to lose O/D capability.
Safety Car
Joined: Sep 2001
Posts: 4,157
Likes: 554
From: Glenbeulah Wi
Use a scanner to see where the car is idling and make the BPW smaller in the idle position. The only difference bewteen the BPW table and the calculated method is the computer looks at the BPW table for a base pulse width for each calculated load position. The spark advance still operates the same as before, it uses the load value to determine what spark advance is commanded from base timing table.
I do not know what modifications you have performed to the car, depending on what has been done you may have a rich idle smell and it may not actually be rich.
Send me a PM with your phone number if you want to discuss the details in more depth.
I do not know what modifications you have performed to the car, depending on what has been done you may have a rich idle smell and it may not actually be rich.
Send me a PM with your phone number if you want to discuss the details in more depth.
Thread Starter
Advanced
Joined: Aug 2003
Posts: 82
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From: Nowthen MN
Here's my mods:
Racetronix fuel pump and wiring harness, 28# injectors, EGR delete, BPP AIR delete, TPIS AFPR, TPIS SS headers and Y-Pipe, high flow CAT, muffler eliminators, Cloyes double roller timing chain, polished aluminum timing cover, de-screened MAF, 4:11 DANA 44, high flow water pump, 160* thermostat, mini-starter, Single Pattern Cam 0.495" lift 276 adv. dur. 222 @ 0.05" 112* LSA, 1.52 Comp Cams Pro Magnum RR, AFR 195 heads, Accel Plug Wires, Bosch Platinum+4 Plugs, Accel Intake manifold, LPE Super Ram Intake Plenum and Runners, LPE 52mm throttle body
PM'd my number also, but I thought I would continue here so others could see too.
Thanks,
-J
Safety Car
Joined: Sep 2001
Posts: 4,157
Likes: 554
From: Glenbeulah Wi
With tunercat if the box is checked it is using the calculated method, unchecked it is using the BPW table. In either case they both still use the MAS tables for determining the fuel load. The BPW method uses the lookup table the calculated method does behind the scenes work to come up with a BPW.
Thread Starter
Advanced
Joined: Aug 2003
Posts: 82
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From: Nowthen MN
I found a good guide for tuning $32B on Craig Moates site tonight and have been studying that. It looks like I had the BPW Calc box checked when I was modifying the BPW table. I'm going to get another log tomorrow night with some lower values and see what happens.
-J
-J
Team Owner
Joined: Mar 2000
Posts: 83,383
Likes: 87
From: Boston, MA
The same in TunerPro, with an X means calculated, without an X means use the BPW Fuel (msec) vs. Load table. The table name may be slightly different in the differen programs.
In either case they both still use the MAS tables for determining the fuel load. The BPW method uses the lookup table the calculated method does behind the scenes work to come up with a BPW.
Safety Car
Joined: Sep 2001
Posts: 4,157
Likes: 554
From: Glenbeulah Wi
Well... sorta. When using the table it is LV8 vs. RPM, but the MAF value is one of the variables used to calculate LV8
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