by FordMuscle Staff

If you're running a carbureted Ford and you haven't seriously considered
any of the Air Fuel measuring devices found in the www.fordmuscle.com tech department archive, we know why. Air Fuel meters appear too complicated, require too much software, provide too much information, and cost too much money. Unfortunately, these barriers prevent many traditional Ford enthusiasts from using this tool to confirm they're running the right jets, power valve, and have their idle mixture screws out the optimum number of turns.

Air Fuel meters have long been a device used by tuners who are mostly
younger and more "techy" than old school Ford hobbyists like most of us. Since a great portion of the tuner crowd rarely gets beyond cold air intakes, performance chips, and exhaust systems, "data logging and laptopping" with robust Air Fuel meters and bundled software offers them a way to personalize their motors much the way we do with camshaft selection. While we are not here to say which group produces more legitimate hot rodders, we are here to say that if you are not using the basic functionality of an Air Fuel meter to tune your carburetor then you're probably pissing in the wind everytime you pick up that long skinny flathead screwdriver.

Innovate Motorsports DB Gauge
This compact Wide Band Air Fuel gauge kit from Innovate Motorsports includes the basics for capturing Air Fuel data. The controller is built right into the cable. While the kit includes data logging software in addition to the 02 sensor and gauge, the cost and simple install make it perfect for simple "live" data tuning. Retails for $289.00.

Air Fuel Meters Dumbed Down
The key to eliminating your hesitation about purchasing, installing, and using an Air Fuel meter on your carbureted Ford starts with looking past manufacturer emphasis on data logging and all the boring software screen shots found
in their marketing materials. Many of the most powerful Air Fuel meters on the market use handheld or nontraditional displays since a tuner's tuning decisions are expected to be made from LOGGED data via a laptop computer. As the Air Fuel Meter market evolves, a few manufacturer's have recognized that not all enthusiasts are terribly concerned about or have the time to study logged Air Fuel data. This is especially true for carbureted street machines who's owners just want to be sure their naturally aspirated motor isn't running too lean or too rich without going to the dyno. In reality, all a traditional street enthusiast needs from their Air Fuel meter is the ability to:

Accurately measure Air Fuel Ratio
Display the "real-time" Air Fuel Ratio
Easily mount the Air Fuel Ratio gauge

The Innovate Motorsports dB Gauge pictured above right is a nice compact unit that fits these basic requirements at a reasonable price. Take note that there is no control box since the brain is built right into the cable.

Live Data Tuning with the ACCEL DFI
The ACCEL DFI Wide Band 02 Kit is a perfect example of a data logging device who's manufacturer understands the need for a mountable gauge even with their most capable Air Fuel meter. While this unit offers more configurable features than most carbed enthusiasts will ever need, the digital gauge does allow you to start tuning immediately from live data (via gauge feedback). For most, this may be the only way they ever use an Air Fuel meter. However, the benefit of a high-end unit like this one is that once you get comfortable live tuning, you then have the option of analyzing 15 channels of logged data with the included DataMap software and ACCEL's Gen 7 logging feature. Another unique feature of the ACCEL DFI Wide Band 02 Kit is its ability to trigger external devices based on RPM, vehicle speed, and Air Fuel Ratio. For now however, let us show you how we got the 650cfm Holley atop our Torino's 351C dialed in with just live data from the ACCEL DFI Wide Band 02 kit.

ACCEL DFI Wide Band O2 Kit Single Channel With Gauge
PN 77062S

After installing the ACCEL unit on the Torino, the first step was to determine target baseline Air Fuel Ratios for idle, cruise, and wide open throttle. The following table was pulled from the ACCEL DFI instruction booklet. The table is by no means an absolute reference for the perfect Air Fuel Ratio for all applications. However, the information provided serves as a great baseline for experimenting to see how idle mixture, primary jet, power valve, and secondary jet adjustments impact power, economy, and drivability. The row highlighted in tan best represented our 351 Cleveland's profile and most street performance Ford V8's. With the chart as a guideline we focused on the first and easiest carb adjustment. What else but idle mixture?

Recommended Baseline Air Fuel Ratio Chart
Engine Type
Stock - little or no modification to engine, 87 octane gasoline
Street/Strip engine - naturally aspirated, performance camshaft and exhaust, 10.0 - 11.0 compression, premium pump gasoline
Race Engine - naturally aspirated, high lift/duration cam, 12:1 or higher compression, high flow heads and exhaust, high octane race fuel

(Idle Mixture, Cruise, and Wide-Open-Throttle Tuning)

In This Article...
Don't let laptops, software, data logging, and information overload prevent you from purchasing an Air Fuel meter to tune your Holley carburetor. FordMuscle breaks down even the most stubborn "old school" Ford man by using only "real-time" (no data logging) air fuel feedback to dial in a Holley.

Wide Open Throttle
Kevin Mikelonis offered his 1972 Torino as a test vehicle to use a simplistic "real-time" Air Fuel tuning approach.

After installing ACCEL's Single Channel Wide Band O2 Kit with gauge, we took the Torino on some backroads for both cruising and wide open throttle runs. Turn up your speakers and listen to the "bird disrupter" as we read our Air Fuel ratios. See Video

Taking real-time note of the Air Fuel Ratio at idle, cruise, and wide open throttle, we virtually had all the information we needed to dial in the 650cfm Holley atop the Torino's 351C. While this particular ACCEL Wide Band 02 meter is capable of much more, we didn't need a computer to make key Air Fuel observations via the digital gauge.

This video shows real-time Air Fuel data prior to any carb adjustments. From the video you'll see the carb was running proportionally rich but was leaning out during transition from cruise to wide-open throttle. See Video









Tech Archives Project Cars Readers Cars Feature Cars