A/F gauges looking for recommendations

[ottawamerc]

I think I will install a permanent A/F gauge and I have done limited research on it so far. I was hoping to get product reviews from you guys, what are you using now?

Scott

[Brightyellow69rtse]

i got a aem unit. i like it but i have nothing to compare it to. having used one i think the average guy is doing himself a disservice by not using one.

[justcruisin]

I use the innovate LMX gauge, tidy install and works flawlessly. It has data logging capabilities but unless you hook up other sensors to input info like vacuum, rpm, throttle position it is pointless. That said - it is a great tool and I wouldn't be without it. For tuning I have hooked up a temporary vacuum gauge next to the o2 gauge and strapped a video camera in front of them so I can review the data. Bit crude but it beats rear ending someone while you are trying to look at the gauge.

[Kern Dog]

Pictures of gorgeous women are distracting, but I'll deal with it.

I have an AEM guage in my Charger. The 02 sensor is in the RH header collector. For years I have tuned engines by smell and throttle response. When I put the guage in I thought the tune was pretty close. I was waaaaaaay off! I was idling richer than the target goal. I was richer at cruise by a huge margain too. The goal is mid 14s at cruise. I was in the high 11s. NO smoke at all either. It smelled okay but the guage told me just how rich I was running. Your nose will fool you.
People used to tell me to "Read the plugs". While this may be effective, reading the guage is an instant measurement of what the engine is doing. Turn a screw and watch the guage move. Advance the timing and watch it move again. Pretty cool stuff. This is one of the few instances where I embrace modern tech.

[Calif240]

+1 for AEM... got it through Summit and it installed easily and performs well. Because it is digital, be sure to not jump it off of a circuit that powers your stereo or you can get feedback through your speakers (buzzing) when the gauge is running.
Terry

[Charger_Dart]

+1 For AEM. I installed their AEM 30-4100 UEGO Controller Gauge and its real nice to have the colored sweep, plus the numbers.

[ottawamerc]

Great thanks guys for the input.   Summit order going in right now.

Scott

[ottawamerc]

I picked up my new AEM  A/F gauge and it was nice and easy to install only issue I found is that there is no under dash mount Why would they not supply that? I will try to source out a 2 1/16" mount now. So far from a quick check I'm getting 12.6 at idle and as I rev it up in neutral it richens up to 10.8-11.2. No road test yet.  So now that I have this info what numbers should I be looking for on my 440 6 pack?

Scott

[justcruisin]

I like to keep my idle around the 14:1 mark, it keeps the plugs clean and runs well. You may be able to lean it out a little further depending on your set up but some cams don't like a lean mix at idle. The idle quality with mine starts dropping off about 14.5:1. You will probably find that the AF ratio will go richer as you bring the revs up in neutral, I wouldn't get concerned about that. I set my idle, cruise, medium load then full throttle in that order. My cruise is mid 14's and full throttle is high 12's. Plug inspection is still important IMO.

[firefighter3931]

I picked up my new AEM  A/F gauge and it was nice and easy to install only issue I found is that there is no under dash mount Why would they not supply that? I will try to source out a 2 1/16" mount now. So far from a quick check I'm getting 12.6 at idle and as I rev it up in neutral it richens up to 10.8-11.2. No road test yet.  So now that I have this info what numbers should I be looking for on my 440 6 pack?

Scott

Scott, you need to check it under load....revving in Neutral doesn't really help. 

Idle = low 14's
Cruise (light load) steady throttle = mid 13's
WOT (heavy load) pedal on the floor = high 12's > low 13's


Ron

[XH29N0G]

Scott,

I have a question.  Where did you feed the line through the firewall?  I am in the process of installing a gauge myself and trying to decide where to send it. 

Thanks.

[Kern Dog]

I ran the lines down through the body plug in the floor just in front of the front passenger seat. It connects into the RH header collector.

[ottawamerc]

Scott,

I have a question.  Where did you feed the line through the firewall?  I am in the process of installing a gauge myself and trying to decide where to send it. 

Thanks.

I'm yet to feed it in as I dont have a place to mount it yet but I did find a body plug just below the brake booster that I will feed it through.

Scott

[ottawamerc]

I picked up my new AEM  A/F gauge and it was nice and easy to install only issue I found is that there is no under dash mount Why would they not supply that? I will try to source out a 2 1/16" mount now. So far from a quick check I'm getting 12.6 at idle and as I rev it up in neutral it richens up to 10.8-11.2. No road test yet.  So now that I have this info what numbers should I be looking for on my 440 6 pack?

Scott

Scott, you need to check it under load....revving in Neutral doesn't really help. 

Idle = low 14's
Cruise (light load) steady throttle = mid 13's
WOT (heavy load) pedal on the floor = high 12's > low 13's


Ron

Thanks Ron
So do I richen it up by the  idle circuit needles  at idle or is it a bump up on the main jets?

Scott

[Kern Dog]

My setup is a bit hard to understand.
Currently it runs damn strong even though it shows to be too rich at all points. I'm idling in gear at 14, light throttle on the road is in the 12.8 range and WOT is as low as 11. I leaned out the primary jets and while it did run leaner, power dropped off. I am running a Demon 850. I have read that I should reduce the primary jets again but drill oversize the PVCR in the primary metering block. This would allow leaner cruise readings with additional fuel in reserve.

[firefighter3931]

I picked up my new AEM  A/F gauge and it was nice and easy to install only issue I found is that there is no under dash mount Why would they not supply that? I will try to source out a 2 1/16" mount now. So far from a quick check I'm getting 12.6 at idle and as I rev it up in neutral it richens up to 10.8-11.2. No road test yet.  So now that I have this info what numbers should I be looking for on my 440 6 pack?

Scott

Scott, you need to check it under load....revving in Neutral doesn't really help. 

Idle = low 14's
Cruise (light load) steady throttle = mid 13's
WOT (heavy load) pedal on the floor = high 12's > low 13's


Ron

Thanks Ron
So do I richen it up by the  idle circuit needles  at idle or is it a bump up on the main jets?

Scott

For now just lean out the idle mixture using the screws to get it where it needs to be. Once the idle mixture is dialed in you can test drive to see where the AFR is at and adjust accordingly.

An increase in jet size will richen the mixture while conversely smaller jets will lean it out. You have the quickfuel plates in your outboard carbs so life will be much easier 

Do you have a jet assortment ? I have 2 holley jet kits available (#64-#99) if you need them. You're welcome to use them and take what you need...then replace later the jets that you used. That will save you from buying stuff you don't need. 

Glad to see you digging in and grabbing the bull by the horns. 



Ron

[ottawamerc]

Ok great thanks Ron I probably will take ya up on the jet offer When I set the idle needles should I adjust the outer carb ones too or just the center carb? I know there is a "whole package" thing going on with idle needles (all 6 of them) I have tried setting them thus far with a vacuum gauge and tach. I also seen on a web page that blocking the air vents for the idle circuits on the outboard carbs and adjusting the needle valves till there is no change in the RPM is the way to set the outer needles I tried that and I couldnt get the results that it claimed I would

Scott

[firefighter3931]

Ok great thanks Ron I probably will take ya up on the jet offer When I set the idle needles should I adjust the outer carb ones too or just the center carb? I know there is a "whole package" thing going on with idle needles (all 6 of them) I have tried setting them thus far with a vacuum gauge and tach. I also seen on a web page that blocking the air vents for the idle circuits on the outboard carbs and adjusting the needle valves till there is no change in the RPM is the way to set the outer needles I tried that and I couldnt get the results that it claimed I would

Scott

Yes, the outboard idle mixture screws must be adjusted along with the center carb. The back carb can be a pain because the idle mix screws are inaccessible unless you remove the carb. I know that there's someone out there that makes a baseplate with angled idle mixture screws to allow adjustment without removing the back carb. 


Ron

[70sixpkrt]

I know that there's someone out there that makes a baseplate with angled idle mixture screws to allow adjustment without removing the back carb.  

Promax carbs sells the base plate with the angled idle mixture screws. You only need one base plate for the rear carb on six packs.
http://www.promaxcarbs.com

[flyinlow]

I have had a AEM on my car for several thousand miles with no problems. Was not sure if it would live with a carb, but it has.