I understand that both E85 and premium gasoline maintain stoich at different air fuel ratios and that both of them are considered 1 lambda by most aftermarket widebands. I just want to know if get a base tune for E85 and fill the tank, will my wideband display 14.7 (1 lambda) as long as my base tune is close?

 

http://www.jegs.com/installationinst...17-30-2310.pdf

Lambda is 1.00, Gas AFR is 14.7, E85 AFR is 9.7.

 

My NGK wideband displays e85 AFR or 9.7:1 as 14.7:1 if that is what you are asking. The target values on the wideband will be the same even though the actual AFR is different.

 

Lambda is 1.00, Gas AFR is 14.7, E85 AFR is 9.7

I understand this...what I'm asking is if I were to say pour in E85 and put it a decent base tune will be aem wideband be able to tell what is 1.0 lambda and report it on the guage as 14.7?

 

I believe it will show you 14.7 AFR still unless you go into the wideband settings and change it to a different lambda. I am not 100% sure so I would like to get confirmation as well. I havent played with this yet!

 

HAHAHAHA!!! This is one of the funnier threads I have seen in a while for sure. The blind leading the blind without a doubt.

The Air / Fuel gauge doesn't give a **** what fuel you are using as long as it is compatible with the sensor being used. It measures lambda and does the conversion and will display the AFR for whatever the wideband displays. So for instance if you have a gasoline AFR gauge (90% of the gauges out there) it will display stoichiometric for ethanol fuel as 14.7 AFR since 1.00 lambda is set for this number using gas.

MANY people use gas AFR gauges for E85 since the same numbers are typically targeted for idle, cruising, and WOT driving. You just have a wider range as a safe zone with E85. This eliminates the need to memorize the required AFR targets if using a E85 AFR gauge which are much lower than gasoline.

 

^ 100% right on.

 

OP your are fine. Your values on your UEGO will need to be exactly the same as gasoline rules however the WOT AFR can be ran as lean as 12.5 and still make power. (Depending on setup)

Cruising nearing 16 for mileage is also common.

Billspec

 

Your gauge will show 14.7:1 at 1.0λ no matter what fuel you are using as it comes default programmed for gasoline.

So unless you reprogram the gauge itself, you will see the 'normal' gasoline ratio numbers, even on E85. 14.7 at stoich, 13s at medium load, 11-12s in boost etc... However your tune is mapped.

 

thanks for the answers guys. One more question...what is a good starting point for timing and fuel considering I have a pretty good tune at 10psi on 93octane. Should I add 2-3* to both the high and low cams in and out of boost? and ~30% fuel across the board as well?