After quite a bit of "tinkering" with my Holley 80457s carb I finally bit the bullet and bought two Summit Air/Fuel ratio gauges, two oxygen sensors and an infrared pyrometer (fancy non-contact thermometer) and installed them.

Some interesting stuff was found out!...

Right off the bat I found that my #4 cylinder wasn't firing. The temperature on all of the header tubes was bout 630 degrees but #4 was only running at about 260 degrees. Turns out I had a bad crimp on the MSD plug wire. Fixed that, ran smoother...

Brought the Maverick over to my local exhaust fellow and he used a torch to cut one hole each in both headers to weld in the oxygen sensor "bung" (fancy nut) so I could screw in the sensors.

After getting it back home I hooked up the Air/Fuel ratio gauges under my dash (again, one each for the left and right cylinder banks) and fired it up. Note that I had a slight "lope" when the car was idling but thought that was due to my Lunati cam, wrong!

It turns out that my idle mixture adjustments were WAY off! The passenger-side cylinders were running very lean and the drivers-side cylinders were running about 95% rich. That sure explains alot!

After tweaking the idle settings to get the mixture even on both banks and dead-middle on the air/fuel ratio gauges (they use LED bar graphs to indicate rich/lean) it runs like a champ!

I also found that my main jets were a hair too small as the engine would go slightly lean after coming off the idle circuit on the carb. Jumping up one shooter size took car of this.

Then, the fun continues... once up to speed and at cruise, I found the gauges indicating very rich so I came down one size on the mains.

Now, except when the electric choke is on, the air/fuel ratio is dead on. The choke makes it run rich until the engine warms up, but then again, its supposed to! The car runs like it just came off the showroom floor!

To verify that the gauges weren't lying to me, I brought the Maverick to a local mechanic that has a shop and builds race cars for the local guys. He hooked up his expensive Sun exhaust-gas analyser and found the settings dead-on. This was the same fellow that told me those gauges were "full of sh*t" but now that he's seen them, said he'll be putting them on!

Total cost was $29.95 per gauge, another $29.00 each for the oxygen sensors and roughly 5 bucks for each "bung" that is welded to the headers. Roughly a grand total of $130 from Summit Racing for a MUCH NEEDED piece of mind.

I have had absolutely zero experience tuning carbs before my 302 conversion but consider myself somewhat of a "gearhead" now by being able to tune the carb to perfection with a little "help" from these gauges. I highly recommend them. Plus they look cool ;)

Note: I have the Weiand 8011 "Action Plus" dual-plane intake on this car. If I had a "single Plane" intake then I could probably get away with only one gauge/sensor since the air/fuel charge would be even across both banks of cylinders.

I made extensive photographs of the installation, carb adjustments, etc and will be posting these soon (maybe in the FAQ Craig? 8)

Anyway, sorry for the long post. If your having carb tuning troubles then I would highly recommend this mod!

This now brings up the number of gauges in my "cockpit" to 10 gauges (I'm also a pilot)

1. Coolant Temp
2. Transmission Temp
3. Oil Temp
4. Oil Pressure
5. Transmission Pressure
6. Volts
7. Manifold Vacuum
8. Fuel Pressure
9. Air/Fuel Ratio-Right
10. Air/Fuel Ratio-Left

When I put the 6-71 supercharger and SuperChiller intercooler I'll have to add the following:

Blower Boost (psi)
Cylinder Head Temp - Right
Cylinder Head Temp - Left
Exhaust Gas Temp - Right
Exhaust Gas Temp - Left
Intake Manifold Temp

If anyone wants the measurements for the floor console to hold all of this stuff let me know and I'll send them (full-size, photocopied).

Oh, I almost forgot, this is just for street driving/show (and to get back at those idjits driving the foreign rat-cars that thing THEY can corner the market on gauges)