[oldman]

I have my wideband set to A/F, I know I should do the 1.0V lambda thing, but I'm an oldman. I have a good idea of my A/F thru the range. Basically I took GMs injection curve and add 10 percent across the board. A normal WOT run now is like 11.6 A/F off idle to 12.2 mid range to 12.5 on the top end. I'll start leaning it out, especially on the low end. My question is what should be the target A/F for max power. I would guess the modern trend on 10 percent ethanol is leaner than the old fashion 12.5 target. Any thoughts. This as 12.0 to 12.7, grunt method works pretty well I guess.


http://www.hotrod.com/articles/wideband-oxygen-sensor/

I change the gauge to lambda today .8523 rich to .9020 lean, max power.

[JANNETTYRACING]

Originally Posted by oldman

I have my wideband set to A/F, I know I should do the 1.0V lambda thing, but I'm an oldman. I have a good idea of my A/F thru the range. Basically I took GMs injection curve and add 10 percent across the board. A normal WOT run now is like 11.6 A/F off idle to 12.2 mid range to 12.5 on the top end. I'll start leaning it out, especially on the low end. My question is what should be the target A/F for max power. I would guess the modern trend on 10 percent ethanol is leaner than the old fashion 12.5 target. Any thoughts. This as 12.0 to 12.7, grunt method works pretty well I guess.


http://www.hotrod.com/articles/wideband-oxygen-sensor/

I change the gauge to lambda today .8523 rich to .9020 lean, max power.

The optimum AFR or Lambda is reliant on many factors.

As a guide only you would shoot for .85 lambda Naturally aspirated or .78 Lambda for supercharged applications.

[Speedy1975]

Why lamda instead of AFR? I personally prefer AFR, makes more sense to me.

[JANNETTYRACING]

Originally Posted by Speedy1975

Why lamda instead of AFR? I personally prefer AFR, makes more sense to me.

Lambda because it is unaffected by alcohol content or fuel type.

I know what you mean I used AFR for years then I finally made the switch.

Also when tuning the Math is easier with Lambda target is .85 and your at .90 you can add 5.5% fuel and be right on.

Stoich value changes with fuel type and manufacturer for example.

Race Gas Stoich Ratings

Sunoco MO2X UL – 14.5
Sunoco 260 GTX – 14.4
Sunoco 260 GT – 13.9
Sunoco 260 GT Plus – 13.7
Sunoco Standard – 14.8
Sunoco Supreme – 14.9
Sunoco MO2X – 14.5
Sunoco HCR Plus – 14.8
Sunoco Maximal – 15.0
Sunoco MaxNOS – 14.9

Turbo Blue Unleaded (100 octane) -13.9
Turbo Blue Unleaded Plus (104 octane) - 13.7
Turbo Blue 110 - 14.7
Turbo Blue Advantage - 14.9
Turbo Blue Extreme - 15.0

VP Street Blaze 100 - 14.16
VP C10 -14.53
VP C16 - 14.77
VP 110 - 15.09
VP MS109 - 13.41

[Speedy1975]

Very informative, thanks Ted.

[JANNETTYRACING]

Originally Posted by Speedy1975

Very informative, thanks Ted.

Your welcome!

[oldman]

OK so my 5% over rich grunt method was go figure about 5% over rich, it needs to be richened about 3% in the lower RPM over stock and mid range is almost spot on, and stock above 4500 is actually slightly rich. I have Mishmoto CAI, MSD intake, 6 LE front cat bypass.

Now my question can I record my data runs by just pushing the record / stop button on the HP tuner? So far I've always use my PC. I tried a couple of times but could not find any log file? My Hondata unit looks just like this and it records just fine and I could find them. Dunno.

[TSloper]

Oldman have you recalibrated your MAF?

[oldman]

I have not... I'm bad. I have just been adjusting the a/f ratio on the PE table. I have to be lean over stock table. I had to be rich with the CAI CAI or it would throw lean codes.

I'm about 10% lean in the mid range that is -12 points or say 1.100 to 1.088 and I'm about 12% lean from 4500 RPM up. I'm tuning via wideband. In general I'm from 12.00 to 12.60 bellshape with a mid point of 12.35, I could keep fooling with it get it slightly leaner. Dunno. I'll send you a log if you want to have a look, any help is appreciated.

Will going with your table on the MAF hose the PE enrichment?

Mishmoto Intake, MSD manifold, L6 front Cat bypass, HP tuner

[JANNETTYRACING]

Originally Posted by oldman

I have not... I'm bad. I have just been adjusting the a/f ratio on the PE table. I have to be lean over stock table. I had to be rich with the CAI CAI or it would throw lean codes.

I'm about 10% lean in the mid range that is -12 points or say 1.100 to 1.088 and I'm about 12% lean from 4500 RPM up. I'm tuning via wideband. In general I'm from 12.00 to 12.60 bellshape with a mid point of 12.35, I could keep fooling with it get it slightly leaner. Dunno. I'll send you a log if you want to have a look, any help is appreciated.

Will going with your table on the MAF hose the PE enrichment?

Mishmoto Intake, MSD manifold, L6 front Cat bypass, HP tuner

No disrespect here but your tuning backwards.

Set the PE at what you want to see on the wide band and tune the MAF to achieve 0 fuel trims and commanded PE.

Ted.

[TSloper]

Originally Posted by oldman

I have my wideband set to A/F, I know I should do the 1.0V lambda thing, but I'm an oldman. I have a good idea of my A/F thru the range. Basically I took GMs injection curve and add 10 percent across the board. A normal WOT run now is like 11.6 A/F off idle to 12.2 mid range to 12.5 on the top end. I'll start leaning it out, especially on the low end. My question is what should be the target A/F for max power. I would guess the modern trend on 10 percent ethanol is leaner than the old fashion 12.5 target. Any thoughts. This as 12.0 to 12.7, grunt method works pretty well I guess.


http://www.hotrod.com/articles/wideband-oxygen-sensor/

I change the gauge to lambda today .8523 rich to .9020 lean, max power.

I have my PE set to 1.150 (.870 lambda) at peak power.


Tim

[TSloper]

Originally Posted by JANNETTYRACING

No disrespect here but your tuning backwards.

Set the PE at what you want to see on the wide band and tune the MAF to achieve 0 fuel trims and commanded PE.

Ted.

Exactly! I would set your LTrims to be 1 or 2% negative. This will keep it from adding extra fuel during WOT.

[TSloper]

Originally Posted by oldman

I have not... I'm bad. I have just been adjusting the a/f ratio on the PE table. I have to be lean over stock table. I had to be rich with the CAI CAI or it would throw lean codes.

I'm about 10% lean in the mid range that is -12 points or say 1.100 to 1.088 and I'm about 12% lean from 4500 RPM up. I'm tuning via wideband. In general I'm from 12.00 to 12.60 bellshape with a mid point of 12.35, I could keep fooling with it get it slightly leaner. Dunno. I'll send you a log if you want to have a look, any help is appreciated.

Will going with your table on the MAF hose the PE enrichment?

Mishmoto Intake, MSD manifold, L6 front Cat bypass, HP tuner

You should be setting your PE where you want it then adjusting your MAF. I can send you my spreadsheet I use if you want it. It will give you a properly fitted MAF curve based on the % error of commanded vs actual lambda.

Once you get the MAF dialed in you can feel confident future PE changes will be damn close to what you are asking for.

[Speedy1975]

Do you guys have to deal with COT protection at all?