Fueling Adjustment Question

84GNGary

Long Time Owner
Joined
Apr 17, 2005
Does percentages apply when adjusting fueling on Eric's chip ?
If my O2's are 900 in first gear and if I lower them to 115 which removes 10%will my O2's drop to 810 ? or is it trial & error ?
I know there is an overall fueling adjustment that also impacts 1st gear fueling too. I just want to know if the math applies.
 
its going to be trail and error. just because you do the math and it should drop it down doesnt mean its going to drop as far as you want it to. take it slow make small adjustments and you will see the # come down. also more boost and more timing will also make the 02's come down. problem is your tuning with 02's that is going to be hard.
 
X2
The Difference between 0.900 and 0.750 on a NB and not linear, therefore "Linear Fuel adjustments" can not be correlated. :cool:
 
Okay, then I know what I have to do. My first gear O2's are almost 900 and 2nd gear is 830-840 at 21 degrees of timing, 15 lbs of boost, alky on 6 and no knock. The car is hesitating during acceleration and dips in the rpms can be seen in DS, probably because it's a little rich :rolleyes: It is so bad that I let off of it before I hit 3rd. I may try raising the boost a little or take out fuel to get my O2's down to normal. I cannot raise the boost too much because my 30lbs'r are maxed out and sometimes get up to +90% duty cycle. So if I leave the boost as is and take out some fuel that should give me some breathing room on my injectors until I get some new ones. I will also try adding some timing too, what would be recommended as the highest timing I should run ? My timing was burned at 19/17 and right now it's set at 21/17.
 
i would take some alky out first. you have the knob on 6 and your only running 15 pounds. i can run 15 pounds on pump gas. anyways turn the alky down some and turn the boost up to 20 and see where the 02's go. im sure it will lean out some but keep an eye on your inj duty cycle.
 
With the timing at 19/17 I could run 15 lbs with no kr and no alky. When I increased the timing to 21/17 I was getting kr even with alky set on 3 with 93octane. At 5-6 no kr, I will also try backing it down some.
 
i would leave the timing set where the chip has it. set your boost to where you want it and then start increasing timing. timing is last IMO
 
Just reading another current thread in the IC section about WB O2 sensor and got a few questions.

Are you using the basic LM-1 $350. kit ?
Does it require a different chip and if so how much does Eric charge for it ?
I looked through the instruction manual, how does it connect to the ecm to control a/f ?
Know any good divorce lawyers ? :biggrin:
 
Getting back to my hesitation/sputtering problem, I also failed to mention I was backfiring sometimes to after heavy acceleration. It all started after I replaced the plugs and wires a few weeks ago. After increasing the 1/2 timing the backfiring did stop up till last night and it popped again. I have to check my ignition system now. My ignition module has two deteriorated terminals but I did get the wires on tight. I do have a spare module I will try. If nothing changes and I pull the plugs will they show me which one has a problem with less than 100 miles on them ?
 
.....Just reading another current thread in the IC section about WB O2 sensor and got a few questions.
Does it require a different chip and if so how much does Eric charge for it ?
I looked through the instruction manual, how does it connect to the ecm to control a/f ?
Know any good divorce lawyers ? :biggrin:

I'll try to comments based on my experiences;
My WB system has 2 output wires: WB and NB
The WB does not tie into the stock ECM set-up, unless you take the NB wire from the system and replace the stock unit in the ECM (Clear as mud? LOL)

You do not need a different chip to run a WB.
The WB can be a stand-alone unit intended to display the AF ratio's you are running at.
Therefore, as a stand alone, it has no control over AF ratios.

Don't know a good lawyer, BUT, I do know a bad one! :eek:


Getting back to my hesitation/sputtering problem, I also failed to mention I was backfiring sometimes to after heavy acceleration. It all started after I replaced the plugs and wires a few weeks ago. After increasing the 1/2 timing the backfiring did stop up till last night and it popped again. I have to check my ignition system now. My ignition module has two deteriorated terminals but I did get the wires on tight. I do have a spare module I will try. If nothing changes and I pull the plugs will they show me which one has a problem with less than 100 miles on them ?

I am no expert, but here is what I would do.
Some may think that "sharing of my actual experiences" is a crock :eek: , but I happen to have the benfit of LOTS of data from my car.:D (Would LOVE some more advice though, seriously :D)

-Fix the ignition system problems as "No good" comes from a bad system
-Reset the chip parameters
-Get overall fueling down in the -10% area
-Leave boost at 14-15
-Set the PAC at 3-4
-Find a looong DESERTED road
-Make a run (Ease into the throttle in third) and monitor KR/O2
-Shoot for around 750mv = 11.2 (Every car is different)
-As you increase the PAC setting and boost, you will need to shoot for a higher O2 number (780-790 = 10.8 )

This "should" be a good start point.
Again, results may vary, and I accept no responsibility for the results, or lack thereof. :biggrin:

PS:
O2 Numbers are based on 93 (10% Ethanol) and 100% VP Meth via PAC
 
I'll try to comments based on my experiences;
My WB system has 2 output wires: WB and NB
The WB does not tie into the stock ECM set-up, unless you take the NB wire from the system and replace the stock unit in the ECM (Clear as mud? LOL)

You do not need a different chip to run a WB.
The WB can be a stand-alone unit intended to display the AF ratio's you are running at.
Therefore, as a stand alone, it has no control over AF ratios.

Don't know a good lawyer, BUT, I do know a bad one! :eek:

I was under the impression that the WB actually controls the a/f and you just dial in your setting, but I guess not. So all it does is give you a highly accurate a/f reading. Then with that information you make the necessary adjustments to the car and disregard the NB O2 readings.



I am no expert, but here is what I would do.
Some may think that "sharing of my actual experiences" is a crock :eek: , but I happen to have the benfit of LOTS of data from my car.:D (Would LOVE some more advice though, seriously :D)

-Fix the ignition system problems as "No good" comes from a bad system
-Reset the chip parameters
-Get overall fueling down in the -10% area
-Leave boost at 14-15
-Set the PAC at 3-4
-Find a looong DESERTED road
-Make a run (Ease into the throttle in third) and monitor KR/O2
-Shoot for around 750mv = 11.2 (Every car is different)
-As you increase the PAC setting and boost, you will need to shoot for a higher O2 number (780-790 = 10.8 )

This "should" be a good start point.
Again, results may vary, and I accept no responsibility for the results, or lack thereof. :biggrin:

PS:
O2 Numbers are based on 93 (10% Ethanol) and 100% VP Meth via PAC

Okay, today I made sure the pass side wires were frimly on the plugs :mad: Set all the chip settings back to 128 and turned the alky down. Besides my kr at 17 mph again the hesitation and sputtering pretty much stopped. My O2's were 790-820 through 1st, 2nd & 3rd. The lowest the duty cycle was during the run was 85% at some points it was 100%. I do get a leveling off at 4600 rpms at the top of first for a few seconds then it starts to climb to 5000 again and shift, the duty cycle at this point is almost 90%, so I think that might be my problem there. I have to get bigger injectors before I can go any further. Most likely I will go with 009's.
 
790's is still rich. You can back the fuel off somemore to get the duty cycle down and add alky to help with fueling and boost. As far as injectors yes you might want to upgrade but just get the high z 60's and be done with it.
 
790's is still rich. You can back the fuel off somemore to get the duty cycle down and add alky to help with fueling and boost. As far as injectors yes you might want to upgrade but just get the high z 60's and be done with it.

I know you always highly recommend 60lbs'r, but will the 009's be sufficient for my car ? What I have done so far as mods is just about as far as I am going to go. I would rather put the put the extra money into a WB sensor or a set of MT's on the rear. If I can get it running good and into the low 13's or possibly high 12's I will be happy.
 
009's should be ok for your setup but these hotair cars like more fuel for some reason.
 
I was under the impression that the WB actually controls the a/f and you just dial in your setting, but I guess not. So all it does is give you a highly accurate a/f reading.
Actually, that is an option on a WB closed loop set-up.
Untill you add such a system, the WB is no more than an "accurate gauge".


........... My O2's were 790-820 through 1st, 2nd & 3rd. The lowest the duty cycle was during the run was 85% at some points it was 100%. I do get a leveling off at 4600 rpms at the top of first for a few seconds then it starts to climb to 5000 again and shift, the duty cycle at this point is almost 90%, so I think that might be my problem there. I have to get bigger injectors before I can go any further. Most likely I will go with 009's.

Sounds like you are in fact out of injector based on the tune, but, you are also running a bit on the rich side.

According to my calulator @0.6BSFC, 28lb injectors are good into the high 13's at 100% DC.
Did you get a chance to remove the overall fuel in the chip? This should reduce DC.
 
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