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Discussion Starter #1
What is a good safe A/F at idol,cruising,and WOT on a turbo car?Also say you have 14.1 is that needing more or less fuel?
 

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To keep it simple for ya.... a lower number, say 10.8, is a lot of fuel, or rich. A number like 15.5 is not enough fuel, or lean. For a turbo car, you want idle roughly 13.2ish (mid 13s). For cruising, mid 14s is good to shoot for. For wide open throttle, mid-low 11s. That's a good starting point.

Are you tuning yourself?
 

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Idle depends primarily on the manners of the camshaft. I typically shoot for an idle AFR of between 13.2 and 14.4. The leaner I can get it to idle and be happy, the happier I am. Cruising AFR should be as close to 14.7 as you can get. If you're experienced, you can lean it out even more (lean burn) for fuel economy. I like to get low 13's/high 12's in the transition area, and richer as I get into boost, topping out between 11.8 and 11.5, depending on the setup.
 

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Idle depends primarily on the manners of the camshaft. I typically shoot for an idle AFR of between 13.2 and 14.4. The leaner I can get it to idle and be happy, the happier I am. Cruising AFR should be as close to 14.7 as you can get. If you're experienced, you can lean it out even more (lean burn) for fuel economy. I like to get low 13's/high 12's in the transition area, and richer as I get into boost, topping out between 11.8 and 11.5, depending on the setup.
Have you noticed much spool up difference when playing with the a/f in the transition area? My old setup was tuned at 11-11.2 under boost, but seems like most think that is too low >:p
 

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Have you noticed much spool up difference when playing with the a/f in the transition area? My old setup was tuned at 11-11.2 under boost, but seems like most think that is too low >:p
IMHO 11.2 in the transition area is way too rich ; you're leaving power on the table there. You will see some improvement in spool and in output by leaning it out.
 

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Discussion Starter #6
Well heres what i came up with setting the fuel pressure close to 40PSI (vac line off)
 

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When it was idling ~1000RPM (15.x AFR), it should be richened up about a point. If it's a stock cam, 14.2 - 14.5 or so should be a good idling point.
 

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Discussion Starter #8
not a stock cam it's a vodoo .499/.522 duration is a 219/227.That video was with some throttle, at idle (900-1000RPM) it reads 15.5-16.5.
 

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If you are running OL all the time, set idle and part throttle to whatever you want - if you still have factory 02 sensors and it is running CL at idle and part throttle, if you set it anything different than the stoich point of the fuel you are using, you'll always be fighting the 02 sensors trying to get things back to where the stoich point is. For gasoline that's 14.64:1, but in reality most gas nowadays is 10% ethonal, so the stoich changes to 14.08 or thereabouts.
Don
 

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Discussion Starter #11
idle: 13 to 14-1 ish
WOT: 11 to 12-1 ish
cruising down freeway: 15 to 16-1 ish.
I will keep an eye on the gauge tomorrow when i take it for a spin.Also having an open DP isnt gonna effect the A/F right?
 

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It depends on where the WBO2 is located in relation to the end of the pipe. But yes, it's likely to read false lean.
 

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Discussion Starter #13
The O2 for the wide band is up in the DP by the throttle body.
 
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