Help solve a AFR arguement

[sikgmc]

A local competitor shop thinks that tuning a car anything leaner then 10.5 is bad. I have had several of his cars come in and they are 10.5 or richer under full throttle. I have retuned these cars at 12.0 to 12.5 and he swears this is way to lean and I am going to blow them up. I even dynoed my bone stock 2010 Camaro and it was 12.8:1 at full throttle. But he still thinks I am leaning these cars out to much.

What AFR's do you guys tune to?

[5_Liter_Eater]

Imo:

12.5-12.9 Na
11.0-11.5 Fi

[sikgmc]

Imo:

12.5-12.9 Na
11.0-11.5 Fi

I agree. He tuned a LS2 at 9.9 NA.

I leaned it out to 12.5 and picked up 40 rwhp. He is even calling my customers and telling them that I don't know what I am doing. I use a Dynojet 224x chassis dyno then street tuning. He uses his desk and a side street. He even tuned a car without driving it. LOL.

[markislive]

Imo:

12.5-12.9 Na
11.0-11.5 Fi

That's what I favor as well assuming it's straight gasoline...

E10 requires a richer mix for max power... I like to split the difference and tune for 5% ethanol

[DSteck]

0.85 lambda on any naturally aspirated vehicle running pump gas (aka not E85).

[ivanls1]

Imo:

12.5-12.9 Na
11.0-11.5 Fi

same here gots to get that fuel going

[KLUG'S SS]

I agree. He tuned a LS2 at 9.9 NA.

I leaned it out to 12.5 and picked up 40 rwhp. He is even calling my customers and telling them that I don't know what I am doing. I use a Dynojet 224x chassis dyno then street tuning. He uses his desk and a side street. He even tuned a car without driving it. LOL.

This guy sounds like a moron who doesnt have a clue as to WTF he is talking about or doing.

[ivanls1]

im sure his cars are riding rich as hell lol

[coryfountain]

0.85 lambda on any naturally aspirated vehicle running pump gas (aka not E85).

why not .85 lambda for E85??

Lambda=afr(measured/commanded)/stoich

.852 lambda = 9.765 stoich(perfect world) and EQ ratio of 1.173.....

so the afr=8.324.(commanded/measured)..... IN THEORY... is there a reason you don't use .85 Lambda?



So i am curious, why not .85 lambda for e85?

But yes on pump gas /e0 and Naturally aspirated... 12.0-12.9 I concur!<--to each his own...

[5_Liter_Eater]

He must have stock in Exxon...

[n0dih]

LOL

He must have stock in Exxon...

[jah81592]

Imo:

12.5-12.9 Na
11.0-11.5 Fi

+1 Agreed

[DSteck]

why not .85 lambda for E85??

Lambda=afr(measured/commanded)/stoich

.852 lambda = 9.765 stoich(perfect world) and EQ ratio of 1.173.....

so the afr=8.324.(commanded/measured)..... IN THEORY... is there a reason you don't use .85 Lambda?



So i am curious, why not .85 lambda for e85?

But yes on pump gas /e0 and Naturally aspirated... 12.0-12.9 I concur!<--to each his own...

E85s maximum power lambda value is richer than that of gasoline. Different fuels can make their peak power at different lambda values. E85 is better off somewhere around 0.75.

[coryfountain]

E85s maximum power lambda value is richer than that of gasoline. Different fuels can make their peak power at different lambda values. E85 is better off somewhere around 0.75.

I am aware of that and totally agree... what i really wanted was your number so that i could try it. .. always good to have an experienced tuners secrets.. all bullshit aside.. Thank you

[markislive]

E85 is better off somewhere around 0.75.

Have to show up at the track with a full tank...lol!

[coryfountain]

Have to show up at the track with a full tank...lol!

Might even want to bring a few spark plugs...might foul one or two..

oh wait he might have them new super E3 plugs.. i bet that is what he is relying on..

[DSteck]

You want to be told a number, and two posts later, you talk shit.

[sikgmc]

Thanks for the info guys. I pulled up the dyno chart from when I tuned another one of my competitors sandrails. This is a LQ9 motor that he claims is 600fwhp. Tell me what you think.

[5_Liter_Eater]

Well yea, when you dyno sand rails in the sand there is always a 44% drivetrain loss.

[sikgmc]

Lol. And 10.23 afr is where all the power is.