AFR What you should know.... LONG - Page 4

lightningkylej · 03-03-2009, 04:25 PM

Quote:

Originally Posted by lightning25

so i have another question then.
when i hooked up my a/f ratio gauge, and when i was tuned, the air fuel gauge was never changed for the fuel i was using, the "up to 10% ethanol" ultra 94. we just hooked it up and changed the configuration in the computer and went for a few test runs to obtain an a/f of 11.7.
so would my a/f have been wrong from the start and will me tune be off then?
i'm sure this was already stated, but how do i go about making sure i have the right a/f reading on my gauge for the fuel i am using.

Sean

Tune your wideband to the SAME AFR no matter the type of fuel.

Z7What · 05-16-2009, 07:42 PM

Different fuels have different A/F, but there all tuned for the same lambda.

Wayne

Don 95Vert · 05-16-2009, 10:35 PM

Z7What · 05-17-2009, 09:18 AM

The wideband reads in Lambda then converts to a A/F number.

Let's say you tune for .775 Lambda. What you do is take the Lambda times that by the stoich of the fuel you run, let's say regular fuel 14.64 and you come up with your A/F number which would be 11.346.

Now let's do the same with E10 fuel with a stoich value of 14.08. .775 times 14.08 is 10.912.

Get it now?

91 Probe GT · 05-19-2009, 11:33 PM

Quote:

Originally Posted by lightningkylej

All I do is pump more fuel. In fact, I had my tuner set my Mafia on setting #3 on the pump gas tune. When I put in the E-85 I change the setting to #2 and it runs pretty well like that. My pump gas tune is near 11.0 and the E-85 tune is high 12's to low 13's.
I haven't had a change to strap it back on the dyno to see what the before and after is. However, I have seen turbo cars pick up 10% more power with the E-85 conversion, with the timing and target AFR the SAME! (600 whp 2.0L on 110 to 660 whp on E85).
That being said, if you are comparing the max safe power on pump gas with the max safe power on E85, then yes you can make alot more power. At the least, compare the E85 to leaded race fuels for a power comparison. More boost, timing, and a leaner AFR all means more power and is very dooable on E85.

So ur saying that having the mafia on #2 pumps more fuel than having it on #3? i would have thought it would be the other way around? I modified my own tune from the really rich tune that it had. spent about 2 hours on the dyno trying to make it scream on 91 octane. there isn't a good tuner near me and the dyno operator here basically just let me have free reign to adjust my tune.

lightningkylej · 05-29-2009, 05:50 PM

My custom tune is set to #3. So I am going from #3 to #2. That is where I get the extra fuel. The higher the number on the mafia, the leaner the tune (except I believe #6 which is stock plus 5 or 10%). Contraversly, the lower the number the richer the tune.

lightningkylej · 06-12-2009, 04:29 PM

I got retuned for the E85 finally. With 16* of timing ramping to 19* on the stock eaton, 8lb lower, sbtb, patriot stage 2 heads, comp stage 2 cams, and built shortblock. I made 475 HP and 570 TQ. The rest of the tuning will be done at the track. Even with the lower timing, I was able to pass my previous best mph 112.45 to 112.83 on the 1/4 while being in 30* warmer temperatures. The ET's only slightly got better because of the 60ft. Went from a previous best of 12.32 with a 1.78 60' to a 12.29 with a 1.86 60'. And it was 84 degrees out side with high humidity this time compared to mid to low 50's last fall when I did my previous best. My tuner will be going to the track with me in a couple weeks to get it dialed in. I'll post up after that.

rvm · 11-21-2009, 12:04 AM

Quote:

Originally Posted by lightningkylej

Tune your wideband to the SAME AFR no matter the type of fuel.

If I may ask . . .

If i was tuned to 11.712 (0.8 lambda) on unleaded gas, and switched to E10 93 octane, would it mean that i should continue to tune for 11.712 AFR with the E10? (i.e 11.712 divided by 14.08 = 0.832 lambda)

05-16-2009, 07:42 PM	#47 (permalink)
Z7What Powered By Eaton! Join Date: Apr 2007 Location: New Orleans, LA Posts: 805 View this user's gallery iTrader: 1 / 100%	Different fuels have different A/F, but there all tuned for the same lambda. Wayne Last edited by Z7What; 05-16-2009 at 08:12 PM..

05-16-2009, 10:35 PM	#48 (permalink)
Don 95Vert Registered User Join Date: Apr 2003 Location: Lost in Space Posts: 137 View this user's gallery iTrader: 1 / 100%	... Last edited by Don 95Vert; 05-16-2009 at 10:39 PM..

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05-17-2009, 09:18 AM	#49 (permalink)
Z7What Powered By Eaton! Join Date: Apr 2007 Location: New Orleans, LA Posts: 805 View this user's gallery iTrader: 1 / 100%	The wideband reads in Lambda then converts to a A/F number. Let's say you tune for .775 Lambda. What you do is take the Lambda times that by the stoich of the fuel you run, let's say regular fuel 14.64 and you come up with your A/F number which would be 11.346. Now let's do the same with E10 fuel with a stoich value of 14.08. .775 times 14.08 is 10.912. Get it now?

05-29-2009, 05:50 PM	#51 (permalink)
lightningkylej CORNFED Paid Member Join Date: Oct 2006 Location: Oklahoma Posts: 571 NLOC member #: 2739 View this user's gallery iTrader: 0 / 0%	My custom tune is set to #3. So I am going from #3 to #2. That is where I get the extra fuel. The higher the number on the mafia, the leaner the tune (except I believe #6 which is stock plus 5 or 10%). Contraversly, the lower the number the richer the tune.

06-12-2009, 04:29 PM	#52 (permalink)
lightningkylej CORNFED Paid Member Join Date: Oct 2006 Location: Oklahoma Posts: 571 NLOC member #: 2739 View this user's gallery iTrader: 0 / 0%	I got retuned for the E85 finally. With 16* of timing ramping to 19* on the stock eaton, 8lb lower, sbtb, patriot stage 2 heads, comp stage 2 cams, and built shortblock. I made 475 HP and 570 TQ. The rest of the tuning will be done at the track. Even with the lower timing, I was able to pass my previous best mph 112.45 to 112.83 on the 1/4 while being in 30* warmer temperatures. The ET's only slightly got better because of the 60ft. Went from a previous best of 12.32 with a 1.78 60' to a 12.29 with a 1.86 60'. And it was 84 degrees out side with high humidity this time compared to mid to low 50's last fall when I did my previous best. My tuner will be going to the track with me in a couple weeks to get it dialed in. I'll post up after that.