Holley Carb, AEM UEGO Questions?

[StraightSix]

Let's the break this down into something more easily understood. An AFR is the Air/Fuel Ratio, right? And, lots of people, even ones without an engineering degree or any exposure to thermodynamics, know what the stoichiometric ratio should be. But, what does that mean?

The stoiciometric ratio is the ratio where the amount of air to the amount of fuel is correct. So, simply, a good AFR for an 800hp turbo whatever is going to be the same for a roughly 100hp Honda, or a 5hp lawn mower.

Adjusting timing to get won't really change anything. All you're doing there is changing when the volume of air is going to be entering and leaving the cylinder. It isn't going to solve the problem of getting too much fuel.

Rejet the carb first, then fine tune with timing. And, all this is assuming that the carb is the right size for the engine in the first place.

[EP3sAreFun]

Let's the break this down into something more easily understood. An AFR is the Air/Fuel Ratio, right? And, lots of people, even ones without an engineering degree or any exposure to thermodynamics, know what the stoichiometric ratio should be. But, what does that mean?

The stoiciometric ratio is the ratio where the amount of air to the amount of fuel is correct. So, simply, a good AFR for an 800hp turbo whatever is going to be the same for a roughly 100hp Honda, or a 5hp lawn mower.

Adjusting timing to get won't really change anything. All you're doing there is changing when the volume of air is going to be entering and leaving the cylinder. It isn't going to solve the problem of getting too much fuel.

Rejet the carb first, then fine tune with timing. And, all this is assuming that the carb is the right size for the engine in the first place.

Sorry man, thats not how AFRs work. a good turbo WOT could be 12:1 or 11:1 sometimes, where a non turbo car will be much leaner. i think the OP needs to find out what a good naturally aspirated AFR for idle and WOT is.

[StraightSix]

Sorry man, thats not how AFRs work.

Uh, yeah. It is. Air-Fuel Ratio is defined as the mass of air to the mass of fuel in a combustion process. This is something that is immutable. It is fact; pick up an text on thermodynamics and look it up.

a good turbo WOT could be 12:1 or 11:1 sometimes, where a non turbo car will be much leaner. i think the OP needs to find out what a good naturally aspirated AFR for idle and WOT is.

Now, let's actually think about this for a second. Knowing how an AFR is defined means that a 12:1 or 11:1 is really freaking rich. This is not good from the stand point of efficiency, or the chemical reaction of combustion. It's not good because not all of the fuel is being used.

It *is* good from the stand point of not blowing up a turbo charged engine. Too lean of a burn in that engine will cause combustion temperatures to rise; the excess fuel helps to keep combustion temps in the individual cylinders down. In a non-turbo charged application, combustion temps aren't as critical so the mixture can be leaned quite a bit.

[EP3sAreFun]

Uh, yeah. It is. Air-Fuel Ratio is defined as the mass of air to the mass of fuel in a combustion process.

You are correct. AFR is nothing more than a unit of comparison of Air to Fuel Vaporl

The stoiciometric ratio is the ratio where the amount of air to the amount of fuel is correct. So, simply, a good AFR for an 800hp turbo whatever is going to be the same for a roughly 100hp Honda, or a 5hp lawn mower.

But once again, this is completely wrong. what do you assume the correct AFR is? is it the point where it runs best? makes most power? or a combination of both? there is no easy answer. it depends on the application.

screw your book on thermodynamics. go read Wikipedia. http://en.wikipedia.org/wiki/Air-fuel_ratio

Knowing how an AFR is defined means that a 12:1 or 11:1 is really freaking rich. This is not good from the stand point of efficiency, or the chemical reaction of combustion. It's not good because not all of the fuel is being used.

12:1 is the correct AFR for my car @ 18psi with WOT. who gives a shit about efficiency when your trying to make 300hp and 400tqe

Don't give advice when your not sure whats going on. *shrug*