Single channel O2

Ed Wright · 07-13-2011, 01:29 PM

Quote:

Originally Posted by Michael Beard

FAST XFI. Currently running in Alpha-N, closed loop, Target A/F at 12.5. Got it to 13.3 on Run #3 of the weekend at MIR, and it wouldn't get out of it's own way.

Question is, is 13.3 to 13.2 a big jump, is 13.3 to 13.0 a big jump, or is 13.3 to 12.5 a big jump? How much is 1,000' DA change likely to affect the A/F ratio (ballpark)?

Michael, 12.5 to 13.0 is a big jump. If you want to email me your calibration file (.gct) file and a log file of a run using it, I can probably put it to, or very close to, 12.5-1, then email it back to you.

Dan Fletcher · 07-13-2011, 02:54 PM

Thank you very much to everyone for the input. I decided to go the Racepak direction through Greg Kelley at Motor Sports Innovations. He came highly recommended from everyone I spoke to, and my phone conversations with him have been outstanding. I'm certainly looking forward to getting the system installed and finally getting my stocker lined out. I know from the comp car how valuable the Racepak is, so even though I'm only getting the Sportsman version, I'm really excited to start acquiring data. Obviously, I'm a moron for not having one before. Now I just need to break down and get one for the poor SS car...LOL...

Thanks again to all...

billy leber · 07-13-2011, 04:02 PM

Obviously...

Chad Rhodes · 07-13-2011, 04:06 PM

Quote:

Originally Posted by Dan Fletcher

Thank you very much to everyone for the input. I decided to go the Racepak direction through Greg Kelley at Motor Sports Innovations. He came highly recommended from everyone I spoke to, and my phone conversations with him have been outstanding. I'm certainly looking forward to getting the system installed and finally getting my stocker lined out. I know from the comp car how valuable the Racepak is, so even though I'm only getting the Sportsman version, I'm really excited to start acquiring data. Obviously, I'm a moron for not having one before. Now I just need to break down and get one for the poor SS car...LOL...

Thanks again to all...

Dan, with your record ( and the one our kids are quickly acquiring ), I don't think anyone can call you a moron.

Adger Smith · 07-13-2011, 04:24 PM

Charles,
You hit the nail on the head with your last post.
It is just Data....not written in stone... I like to use the EGT cross reference along with reading plugs. As far as customers being able to read them you are right.. Some know a little about it some know a lot and some know a lot less than they think. Most of my customers/friends are told to learn as you go. Look at the plug and make a change you think is correct (that all other data suggests). Then after the tune up change look at the plug and see what changed. They should learn trends and what to expect. Like you said...Reading the plug Keeps the tune up honest..
Let's talk "Air" ...
Someone has mentioned DA, a lot. Well I'm not so sure all your faith should be put in DA. Doesn't everyone know you can get the same DA by having several totally different conditions? (Baro, Vapor Pressure, Humidity, Temps, ect..) It's when the conditions change that the engine goes from lean or rich or rich to lean. A good carb tuner knows he has a slight window that the carb will take care of when conditions change, a little, but not when they move a lot. I've always worked with mechanical FI that is Stupid. It only changes when you make the change or the pump is going away and you loose pressure, volume or both.....
This could be a good discussion..
OK What you guys say???
Beard, do you remember when we got bitten when we forgot to monitor the vapor pressure? :~)

Ed Wright · 07-13-2011, 06:25 PM

Different brands of wide bands often don't read the same. Different engine combos don't want the same air/fuel ratio. My 358" SS engine with VP C11 likes 12.6 to 12.8, my old 383" 14.25-1 compression bracket engine on VP C12 likes 13.3-1 to 13.4-1, all according to my FAST XFI, and my old DynoJet dyno wire band agreed.

The LM1, LM2, LC1 stuff that came through my shop (kids installed them in their cars) were all over the place, some showed richer than mine, some leaner.

BigStuff3 systems agreed with my dyno wide band also. You just need to know what your car likes according to your wide band.

Like Adger said, it's just data. Only a reference.

07-13-2011, 02:54 PM	#2
Dan Fletcher Sponsor Join Date: Feb 2006 Location: Churchville, NY Posts: 493 Likes: 129 Liked 1,045 Times in 70 Posts	Re: Single channel O2 Thank you very much to everyone for the input. I decided to go the Racepak direction through Greg Kelley at Motor Sports Innovations. He came highly recommended from everyone I spoke to, and my phone conversations with him have been outstanding. I'm certainly looking forward to getting the system installed and finally getting my stocker lined out. I know from the comp car how valuable the Racepak is, so even though I'm only getting the Sportsman version, I'm really excited to start acquiring data. Obviously, I'm a moron for not having one before. Now I just need to break down and get one for the poor SS car...LOL... Thanks again to all... __________________ Dan Fletcher 1781 STK, SS, COMP, SG, SC DAN FLETCHER TRAILER SALES

07-13-2011, 04:24 PM	#5
Adger Smith VIP Member Join Date: Dec 2001 Location: Texarkana Ark/TX Posts: 2,446 Likes: 575 Liked 880 Times in 311 Posts	Re: Single channel O2 Charles, You hit the nail on the head with your last post. It is just Data....not written in stone... I like to use the EGT cross reference along with reading plugs. As far as customers being able to read them you are right.. Some know a little about it some know a lot and some know a lot less than they think. Most of my customers/friends are told to learn as you go. Look at the plug and make a change you think is correct (that all other data suggests). Then after the tune up change look at the plug and see what changed. They should learn trends and what to expect. Like you said...Reading the plug Keeps the tune up honest.. Let's talk "Air" ... Someone has mentioned DA, a lot. Well I'm not so sure all your faith should be put in DA. Doesn't everyone know you can get the same DA by having several totally different conditions? (Baro, Vapor Pressure, Humidity, Temps, ect..) It's when the conditions change that the engine goes from lean or rich or rich to lean. A good carb tuner knows he has a slight window that the carb will take care of when conditions change, a little, but not when they move a lot. I've always worked with mechanical FI that is Stupid. It only changes when you make the change or the pump is going away and you loose pressure, volume or both..... This could be a good discussion.. OK What you guys say??? Beard, do you remember when we got bitten when we forgot to monitor the vapor pressure? :~) __________________ Adger Smith (Former SS)

07-13-2011, 06:25 PM	#6
Ed Wright Veteran Member Join Date: Mar 2005 Location: Sand Springs, OK Posts: 8,132 Likes: 896 Liked 390 Times in 170 Posts	Re: Single channel O2 Different brands of wide bands often don't read the same. Different engine combos don't want the same air/fuel ratio. My 358" SS engine with VP C11 likes 12.6 to 12.8, my old 383" 14.25-1 compression bracket engine on VP C12 likes 13.3-1 to 13.4-1, all according to my FAST XFI, and my old DynoJet dyno wire band agreed. The LM1, LM2, LC1 stuff that came through my shop (kids installed them in their cars) were all over the place, some showed richer than mine, some leaner. BigStuff3 systems agreed with my dyno wide band also. You just need to know what your car likes according to your wide band. Like Adger said, it's just data. Only a reference. __________________ Ed Wright 4156 SS/JA

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07-13-2011, 04:02 PM	#3
billy leber Member Join Date: Apr 2009 Location: most places Posts: 211 Likes: 0 Liked 10 Times in 1 Post	Re: Single channel O2 Obviously... __________________ Billy Leber 1150 SS, 1050 SG, 1962 STK, 185 SC