CB Performance Air/Fuel meter?, Who's used it, and with what kind of results?? Options

[jaybird840]

Hey Gang,
I've been eyeballing the CB Performance Air/Fuel meter to assist in dialing my carbs in. My eye is not well-trained enough to do it by looking at the spark plugs, so I though an A/F gauge might do the trick. It's about $130 for a three-wire heated O2 sensor, gauge, and exhaust bung. Anybody used it? Any others I should be looking at? I'd consider the Innovate unit, but it's over $300, and until I megasquirt, I don't think logging data will be that useful for my street only car. Also, as the car has dual carbs, would it be a good idea to weld in two bungs(or even four) so that I could switch between cylinder banks, or even individual cylinders? My thought is to mount the gauge in my existing clock (non-working) hole in the console. Any advice related to A/F meters and carbs is welcomed... Thanks!!

--Jaybird

[PeeGreen 914]

If you need something to get you carbs dialed in correctly you should get one of these...
http://www.automotion.com/productpage.aspx...amp;name=Unisyn

[jasons]

I have it, but non heated. If you do any homework on O2 sensors, you'll find these narrow band ones don't do much. Since mine isn't heated, it doesn't even work for at least a 1/2 hour. Honestly, I wouldn't recommend it. I think you really need an exhaust gas analyzer for what you want to do.

The only reason I have it, I bought a euro race header with a bung and needed something to fill the hole. And, my buddy gave me the gauge and sensor. Otherwise, I'm glad I didn't pay any money for it.

I should be clear, my car is DJET still too.

[Aaron Cox]

If you need something to get you carbs dialed in correctly you should get one of these...
http://www.automotion.com/productpage.aspx...amp;name=Unisyn

that only makes sure the butterflies are open the same amount.... (air flow)

you have NO IDEA what your A/F ratio looks like with that tool.

[Brando]

Get a wideband unit, not narrow band. LM1 is the ticket.

[PeeGreen 914]

If you need something to get you carbs dialed in correctly you should get one of these...
http://www.automotion.com/productpage.aspx...amp;name=Unisyn

that only makes sure the butterflies are open the same amount.... (air flow)

you have NO IDEA what your A/F ratio looks like with that tool.

If you have your jetting right, timing set properly, and fuel pump pressure right why would you need anything other than to get the airflow right to dial in the carbs?

[TimT]

This is a very good wide band unit, and the price is right

NGK wideband

We have a few of the NGK units along with all the other ones we have picked up over the years. We have PLX, Motec,FJO, Innovate, Tech Edge..to many

[Aaron Cox]

If you need something to get you carbs dialed in correctly you should get one of these...
http://www.automotion.com/productpage.aspx...amp;name=Unisyn

that only makes sure the butterflies are open the same amount.... (air flow)

you have NO IDEA what your A/F ratio looks like with that tool.

If you have your jetting right, timing set properly, and fuel pump pressure right why would you need anything other than to get the airflow right to dial in the carbs?

the subject was on A/F mixtures and not Airflow Synching (IMG:style_emoticons/default/smile.gif)

Alot of IF's in your statement (IMG:style_emoticons/default/tongue.gif)
jetting deserves a thread all to its own....

[jaybird840]

Yes, proper jetting is my main concern in all of this....

[Joe Ricard]

1st off I have a CB narrow band in my tool box. It works to get you in the ball park. it will tell you rich from lean. that's about it.

I now have a wide band and am able to jet down to half sizes and make great power great milage and throttle response.

I can see a difference in the reading between hot humid days and cold dry days. each requiring different jets.

I got lots of jets.

[john rogers]

I have one in my race car and an O2 sensor on each stinger. I switch them back and forth on a race weekend to see what the O2 reading at full throttle is as that is the only place I really worry about it. If I am on a clockwise track like Willow Springs it plugs onto one side and at the CCW tracke like the CA Speedway, it plugs onto the other due to float movement of the Webers on lond turns.

[tommy914]

1st off I have a CB narrow band in my tool box. It works to get you in the ball park. it will tell you rich from lean. that's about it.

I now have a wide band and am able to jet down to half sizes and make great power great milage and throttle response.

I can see a difference in the reading between hot humid days and cold dry days. each requiring different jets.

I got lots of jets.

Joe, What wide band unit did you go with?

[Brett W]

There is a reason all the wideband units are kinda pricey. They work. Unlike the narrowband pretty light shows. Those are useless. If you tune a bunch of engines get a wideband unit, otherwise make a dyno run and use theirs. It will do the job you need.

Your dealing with carbs, there ain't a whole lot to them. You can't change every operating zone like you can with EFI. You jet the thing for WOT and idle. Just do a plug cut for WOT jetting and go with 57-65 idle jets. Weather will play a role in what you jet for on the idle size.