Lean burn for carburetor engines (posibly fuel injected too)

[Cepheuz]

if you achieve your target speed and load, i think leaning the mix would be benefitial

can a person simply make a meter devices to inject air into the manifold, possibly trough the brake servo vacuum line?

tap into the ignition vacuum advance, the fuel enrichment and a plenum vacuum, when the vacuum advance is activated and the enrichment is not open the vacuum to the plenum and it will enrich the mix

then you would have a normal lean mix that doesn't hinder acceleration or load and you can adjust the lean mix even further by metering the leak amount

it's just right now an idea, but i think a plausible one

[MetroMPG]

Don't forget that running a lean ratio can cause increased production of oxides of nitrogen as a result. Many people who appreciate clean air and a blue sky wish to avoid this.

[Frank Lee]

Years ago dashboard mixture controls for carbs were available from the factory and the aftermarket. I dimly recall Holley offering such a carb, I think in the '70's. Googling "holley carburetor dash mixture adjustment" reveals a number of leads.

[blueflame]

I've seen a float bowl mod that lets you adjust the main jet with a screw driver (under the bowl), ideally with a dynotune you can adjust the correct mixture....

Be careful going too lean under load/hot as engines dont like this.

[some_other_dave]

Originally Posted by Cepheuz

can a person simply make a meter devices to inject air into the manifold, possibly trough the brake servo vacuum line?

How about injecting inert gases in instead? That should help prevent the NOx formation from burning a lean mixture. Perhaps we could use something readily available on the car already, like air that has already been combined with fuel and then burned?

I know--we can tap into the exhaust, and then at low loads (like at cruise) we can recirculate the exhaust gases into the intake manifold! We can call it EGR, for Exhaust Gas Recirculation!



-soD