BLM tuning?
#1
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Car: 1988 Chevy Camaro Hardtop
Engine: Turbocharged/Intercooled 3.1
Transmission: World Class T5 5 Speed
BLM tuning?
I'm curious... if I'm idling with a BLM of 118 (rich - the ecm is removing fuel to attain 14.7:1) then is this true -
118/128 = 0.921875
1 - 0.921875 = 0.078125
= I need to remove 7.8% fuel at idle?
Wondering if I'm seeing this correctly....
118/128 = 0.921875
1 - 0.921875 = 0.078125
= I need to remove 7.8% fuel at idle?
Wondering if I'm seeing this correctly....
#2
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Car: 89 S10 Blazer
Engine: Built 4.3L V6 TBI
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Axle/Gears: 7.65/Zexel/3.73
Re: BLM tuning?
Originally posted by Doward
I'm curious... if I'm idling with a BLM of 118 (rich - the ecm is removing fuel to attain 14.7:1) then is this true -
118/128 = 0.921875
1 - 0.921875 = 0.078125
= I need to remove 7.8% fuel at idle?
Wondering if I'm seeing this correctly....
I'm curious... if I'm idling with a BLM of 118 (rich - the ecm is removing fuel to attain 14.7:1) then is this true -
118/128 = 0.921875
1 - 0.921875 = 0.078125
= I need to remove 7.8% fuel at idle?
Wondering if I'm seeing this correctly....
Current VE Cell value * 118/128 = New VE Cell value
I tend to be a little more conservative and cut the difference in half, so it looks like this:
Current VE cell value * ( (118+128)/2 ) / 128 = New VE cell value
You end up burning more chips, but it helps keep you from making a bunch of big swings in the map if your BLMs are way off.
Teeleton
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Car: 91 Formula WS6 (Black, T-Tops)
Engine: 383 MiniRam (529 HP, 519 TQ - DD2K)
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"Half way" moves are generally better in my testing.
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Car: check
Engine: check
Transmission: check
Originally posted by Bill usn-1
If your not adding VE1 and VE2 first..aren't you already making less of a change?
If your not adding VE1 and VE2 first..aren't you already making less of a change?
RBob.
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Car: 1988 Chevy Camaro Hardtop
Engine: Turbocharged/Intercooled 3.1
Transmission: World Class T5 5 Speed
Whoops...
MAF based '302, $3A, HNL![Wink](https://www.thirdgen.org/forums/images/smilies/wink.gif)
I only have a 2D LV8 vs PW table here to go off of![Smilie](https://www.thirdgen.org/forums/images/smilies/smile.gif)
Subtracting 3% (scale by .97) - lets see what happens![Wink](https://www.thirdgen.org/forums/images/smilies/wink.gif)
*EDIT*
Idles at 122 BLM now... It took a few seconds for the BLMs to settle down - they started at 140, and worked down to 122, settling there. I take it that it is because the ECM stores the previous BLMs, which, when taken with the 3% decrease in fueling, would have had the ecm 'relearn' the BLM?
MAF based '302, $3A, HNL
![Wink](https://www.thirdgen.org/forums/images/smilies/wink.gif)
I only have a 2D LV8 vs PW table here to go off of
![Smilie](https://www.thirdgen.org/forums/images/smilies/smile.gif)
Subtracting 3% (scale by .97) - lets see what happens
![Wink](https://www.thirdgen.org/forums/images/smilies/wink.gif)
*EDIT*
Idles at 122 BLM now... It took a few seconds for the BLMs to settle down - they started at 140, and worked down to 122, settling there. I take it that it is because the ECM stores the previous BLMs, which, when taken with the 3% decrease in fueling, would have had the ecm 'relearn' the BLM?
Last edited by Doward; 08-20-2005 at 01:16 AM.
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#8
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Car: 1988 Chevy Camaro Hardtop
Engine: Turbocharged/Intercooled 3.1
Transmission: World Class T5 5 Speed
Anyone? Without the $3A code in front of me, I can't be sure, lol.
Did a nice 2nd/3rd gear run. My AE bites right now. AFR shoots to 16-18:1 when I stab the pedal.
So I did the following -
Changed:
Accel Enrich Delta TPS PW Scale Factor from .313 to .324
Also:
Added .070 to the entire AE pulse mult vs Coolant table
I also noticed that from 3300rpm, my AFR went from 12.2ish:1 to 13:1 up to 14.5:1 @ 5000 rpm (where I let off)
So I increased my % change AFR @ WOT vs RPM as follows:
................Old values..................New values
3200...........4.3..............................4.3
3600...........4.7..............................5.1
4000...........5.5..............................6.3
4400...........5.5..............................6.6
4800...........5.5..............................7.0
5200...........5.5..............................7.4
5600...........6.3..............................7.4
6000...........6.3..............................7.8
6400...........6.3..............................7.8
Off for another datalog... we'll see what happens![Smilie](https://www.thirdgen.org/forums/images/smilies/smile.gif)
*EDIT*
meh.. my neighbor's awake. I really have to get rid of this Flowmaster 40 series (WAY too damn loud!). Of course, it's 2:20am right now... I can see that he'd be a little peeved
He's not really angry... Bob's pretty cool. Just flipped his porch light for me, to let me know I woke him up (little code we have - I tend to go overboard - if his porch light is on, I need to quiet it down).
Anyway, I'll report back tomorrow how this turned out. I'm also thinking I'm going to disable closed loop operation, get the fueling where I want it based on the WB (I'll be directly in control of the AFRs, with no ecm 'self tuning' going on, to at least get me in the ballpark) and then I'll go back to closed loop tuning it.
I'll be back tomorrow, with results.
Did a nice 2nd/3rd gear run. My AE bites right now. AFR shoots to 16-18:1 when I stab the pedal.
So I did the following -
Changed:
Accel Enrich Delta TPS PW Scale Factor from .313 to .324
Also:
Added .070 to the entire AE pulse mult vs Coolant table
I also noticed that from 3300rpm, my AFR went from 12.2ish:1 to 13:1 up to 14.5:1 @ 5000 rpm (where I let off)
So I increased my % change AFR @ WOT vs RPM as follows:
................Old values..................New values
3200...........4.3..............................4.3
3600...........4.7..............................5.1
4000...........5.5..............................6.3
4400...........5.5..............................6.6
4800...........5.5..............................7.0
5200...........5.5..............................7.4
5600...........6.3..............................7.4
6000...........6.3..............................7.8
6400...........6.3..............................7.8
Off for another datalog... we'll see what happens
![Smilie](https://www.thirdgen.org/forums/images/smilies/smile.gif)
*EDIT*
meh.. my neighbor's awake. I really have to get rid of this Flowmaster 40 series (WAY too damn loud!). Of course, it's 2:20am right now... I can see that he'd be a little peeved
![Smilie](https://www.thirdgen.org/forums/images/smilies/smile.gif)
Anyway, I'll report back tomorrow how this turned out. I'm also thinking I'm going to disable closed loop operation, get the fueling where I want it based on the WB (I'll be directly in control of the AFRs, with no ecm 'self tuning' going on, to at least get me in the ballpark) and then I'll go back to closed loop tuning it.
I'll be back tomorrow, with results.
![Smilie](https://www.thirdgen.org/forums/images/smilies/smile.gif)
Last edited by Doward; 08-21-2005 at 01:23 AM.
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Car: 88 V6 'bird/89TBI bird/85 T/A
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Transmission: V8 T-5/700R4 x2
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Re: BLM tuning?
I'm bringing this old dog back from the dead (much like the car it will help to repair hahahahah.)
In my beginnings to tuning, I am going to mess around with my 302 ECM and $3A stuff to learn what all this craziness means to the car.
There's a lot of good stuff here to help me out.
In my beginnings to tuning, I am going to mess around with my 302 ECM and $3A stuff to learn what all this craziness means to the car.
There's a lot of good stuff here to help me out.