06-02-2007, 07:58 PM #1
Air Fuel Ratio ?? Help, Get me to the Bug
Today I ran 78.5 @ 7500 RPM's which made me feel good.
Bad thing is that the AFR was 14.7 under 100% load and EGT's in the # 3 cylinder were 1580 degrees.
My EGT sensor leads were to short so I only had #3 hooked up.
What are you guys shooting for when tunning as far as EGT's and AFR #'s?
I understand that EGTS are all different but what is the ballpark?
Running this lean do you think the ski would feel like a dog?
06-02-2007, 08:01 PM #2
06-02-2007, 08:17 PM #3
If you are using the instrument grade Autronics A/F meter (and expensive but very accurate) then 14.7 is way to lean and you should have had a meltdown. My guess is your numbers of A/F are off and not using it. but if you are....
Try to fuel around 11.6-11.9 under 100% load.
EGTs can not be compared on a internet forum because the placement of the sensor needs to be identical to the users.. and I mean its not were its placed but ALSO how far in you put the tip of the sensor.
You will get apples to oranges for sure
i run 1480-1500F on my Ski and 1860-1880 on my nitro Top Fuel race bike.. numbers only mean to you what you have to your combo.
06-02-2007, 08:26 PM #4
06-02-2007, 08:52 PM #5
If you see 14 afr under a load @ wot, you better back off quick. I have run 13.0 and made it out ok, but never 14, or 14+.
It's going to be hot at the bug...the hotter the air, the more expanded the air molecules are. This means you might not need quite as much gas as normal. You still need to add fuel for your set up though.
Last edited by BDNJ; 06-02-2007 at 08:55 PM.
06-02-2007, 08:53 PM #6
- Join Date
- Jan 2006
- Rydal, Georgia U S A
,more fuel 1580 degrees... Too hot! Race fuel will let you live for a little while, MS109
06-02-2007, 08:54 PM #7
06-02-2007, 09:01 PM #8
06-02-2007, 09:02 PM #9
Shawn I have an idea if it will work.
Looking through my map 2/3 of it is way off compared to the Igni map that everyone is running.
Can I build a timing map by inputing the same curve that other guys are running or are there other variables to consider that make them to far apart to do this.
1/3 of my map is very close to the Igni map but the other 2/3 is totally different.
What do you think?
I am running the same ARF gauge that everyone else here is running. I know it is not an Autronics but it is better than nothing.
There is only one place to install the sensor in the manifold so everyones is more or less in the same place as far as placement.
06-02-2007, 09:02 PM #10
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