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Air Fuel Ratios & SU Carbs

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martx-5

martx-5

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There's a thread going on in the MG forum that talks about air fuel ratios. It's apparent that many of us are starting to take advantage of some modern technology by using O2 sensors and monitoring their feedback under different driving conditions. This becomes even more important with modified engines, as running too lean or rich can cause running problems, or worse yet, things like melted pistons! :sick:

So, what if you find that you need to adjust those air fuel ratios. Where do you start??

Well, there's a little program that you can down load that will help in needle selection for SU carbureters. It compares your current needle with a selection of others and shows how much leaner or richer they will be under different rpm conditions.

There are two versions of the download...one is free, and then there is an expanded version for a charge of 10 pounds.

I have no affiliation with this, but I did download the free software and it's very informative and should make any changes I'm contemplating in my AFR curve to be that much easier.
 
Using an A/F ratio meter makes tuning ANY carbs infinitely easier.

Let me restate that. Using an A/F ratio meter makes tuning ANY carbs CORRECTLY infinitely easier.

I did this well over a year ago and love the setup. There are others that are just as good and probably better today, with computer hook ups as well as nice round gauges that will fit in your dash or console.

A/F Ratio Meter Install
 
Not unless you had a complicated EFI system with an adjustable computer tweaking method.

The mechanical adjustments are a pain to do continuously (for those with sore backs) bending over under the hood, let alone impossible from any other angle.
 
Mine is that way
Brosky said:
Not unless you had a complicated EFI system with an adjustable computer tweaking method....
Click to expand...

Finally received my redone chip for my puter. I can now change while on the fly.

Finally picked up the last parts from the PC'ers. Ready to reassemble.
 
Lets get some photos and details Don!!

You know the rules.
 
Paul- Here's the computer chip
SSL20494.jpg


Don't know if that is what you meant
 
racingenglishcars said:
How about an O2 sensor feeding an amplifier board connecting a piezoelectric actuator which is mounted to the bottom of the carb jets.
Click to expand...
Might as well go PI

Interesting idea though.
 
Uh, Don.....

You can stop with the teasing now and show us a bit more of what you're doing than one little module.
 
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