duty cycle question...switched to e85, fibbed my injector flow rate table by 30%

[ryans1000]

Switched to e85. So I know the proper way would be to change the stoic value in efilive but I'm in a hurry to tune for a drag race this weekend and I don't know if changing the stoic value in efilive will effect other areas in my tune or my wideband readout on the laptop

So for now I fibbed my injector flow rate table by 30% because e85 require 30% more fuel . Did this to get started with my e85 tune for this weekend.

I have Siemens 60lb'ers. I am speed density, open loop with a vacuum referenced regulator. I switched my injector flow rate from 9.24 g/s to now 7.1 g/s .

This sound right? and will my duty cycle displayed be correct still?

[joecar]

It would have been simpler to set B3601 to the correct value (no other change required).

And of course you will be logging wideband lambda or EQR (and not AFR).

Fixed typo.

[ryans1000]

you mean b3601 right? what is better to get used to , reading in lambda or EQR ?

[joecar]

Yes, B3601.

[joecar]

EQR qucikly tells you how much richer than stoich you are (e.g. EQR 1.18 tells you your are 18% richer).

Lambda and EQR are related like this: EQR = 1/Lambda

Some people get used to Lambda, it is personal preference, but make sure you do not confuse/switch between the two.

[joecar]

For example:
- you look at GM.EQIVRATIO to see what the PCM is commanding;
- you look at EXT.WO2EQR1 to see what the wideband reports;

then your BEN correction is EQIVRATIO/WO2EQR1 which is the same as EQIVRATIO*WO2LAM1.

[ryans1000]

i'll have to switch over to lambda or eqr soon. but do you think my duty cycle is accurate with my fib on the injector flow rate?

[joecar]

Yes, the 33% difference in stoich AFR is the same as your 33% difference in IFR... it will be ok most of the time, but it won't quite follow during transients.