E85 AFR?

[Wahoo]

So I'm running e85 on my HOT air, I have an AEM wideband and no intake temp sensor(HOT air). Cold start the wideband shows 10.0 air fuel (gas scale) Which it idles and doesn't stall but definitely idles bad and slowly the AFR goes towards 14.7 and right around 10.5 the idle smooths out and gets better as it warms up.

So I'm wondering if it's too rich at first start, I have a turbo tweak chip.

I have a MAF translator with extender chip, LS1 maf. So I can change the base dial to take some out possibly, not sure how that would effect part throttle tune.

At WOT my AFR is 11.0 generally, what do I want WOT to never go past for AFR?


Thx

 

[Grand_87_national]

Not sure how much of a difference the intercooler makes regarding this, but, I'd assume it does. My '87 sparks to life (rather quickly) on e85 and also seems to hang out on the rich end of the spectrum until it's warmed up, then it'll usually idle around 14.5:1. It seems to like it here, and idles very well, so I've never thought about adjusting it. My wot tune is also on the rich side (10.5:1 @ 23 psi) but, next spring I'll get in some more track time to make adjustments and see what the car likes. As far as a "no-no" number to avoid... there is no magic number as every car is a little different and lean for someone else, might be perfect for you. I've heard of some guys going as lean as 12:1 or more, while others make their max power around 11:1. The fuel is very forgiving under lean conditions, from what I've read. If there isn't a dyno or track handy, you'll likely want to read the plugs to see what your car likes. Now, this is all based off of my personal research for my intercooled car, but I'd imagine most of the tuning info is somewhat universal. Good luck!

 

[Toby_Goodmk]

I idle on E85 at 9.5:1, WOT 7.5:1. If you are WOT at 11:1...geesh....

 

[John Larkin]

11 is the gas scale not the ethanol scale.

 

[Wahoo]

I idle on E85 at 9.5:1, WOT 7.5:1. If you are WOT at 11:1...geesh....

I'm on gas scale. I feel like leaving it in gas scale might make it less confusing as well.

My car idles at 14.7 on gas scale warmed up, wot is 10.8-11.00, but was curious if I can fix my idle with my maf translator dials because I think cold start is too rich, just to start it I have to give a little gas and then it runs a little rough

 

[Eric Stage I]

On a cold start, what is your fuel pressure, line on and line off?

 

[TurboDave]

I idle on E85 at 9.5:1, WOT 7.5:1. If you are WOT at 11:1...geesh....

You're on gas scale running those numbers??

 

[Toby_Goodmk]

I am on a FAST system, so I dont use a certain scale

 

[Ttype6]

I'm on gas scale. I feel like leaving it in gas scale might make it less confusing as well.

My car idles at 14.7 on gas scale warmed up, wot is 10.8-11.00, but was curious if I can fix my idle with my maf translator dials because I think cold start is too rich, just to start it I have to give a little gas and then it runs a little rough

I have the same problem with my program. I'm sick of the thing washing my cylinders and chugging during cold start so I set my translator to 2 on the base setting which is 10 percent rich for my 3.5" maf. The computer will learn from the O2 sensor and the block learn will fall. In my case,to 115 at idle. When I start the engine when it's cold,I switch the maf base to 3 which is 10 percent lean. Then I start the engine. The car starts nice and smooth,then I watch the a/f to determine when to turn the switch to 0 which is standard base for my 3.5" maf. Then,as the a/f numbers rise,I turn the knob to 2 which is back to the 10 percent rich setting.

 

[Ttype6]

I can change the base dial to take some out possibly, not sure how that would effect part throttle tune.

If you set the base to 3,which is 10 percent lean,it will start better but will re-learn and you will be back to the same rich start situation. What ever base setting you choose,the computer will re-learn and it will run exactly the same as it would at another base setting.

 

[1KWIK6]

I believe that the Translator switch settings are only checked at "key on" and cannot be updated on the fly. Then again, that may only pertain to Extender chip users. Perhaps Bob or Eric will chime in to confirm?

 

[Ttype6]

I believe that the Translator switch settings are only checked at "key on" and cannot be updated on the fly. Then again, that may only pertain to Extender chip users.

Do you think I pulled the procedure that I described and perform for every cold start on my engine with an Extender Extreme chip,out of my ear?

 

[Grand_87_national]

I idle on E85 at 9.5:1, WOT 7.5:1. If you are WOT at 11:1...geesh....

I'm on gas scale, as is o.p.

 

[1KWIK6]

Bob reminded me that it is the "dip switches" that cannot be changed without a key off cycle. Carry on...