AIR TO FUEL RATIOS

[weggl]

Air /fuel ratios

To all the smart men on this site who know more about air to fuel ratios than I , I am asking for some input.
I an currently running a 1996 1800cc Corola EFI ON 19/1 AIR FUEL RATIO.
MY CELL IS PUTTING OUT AROUND 1.2 L/M of Ho gas and I am also running water injection at the rate of 500ml per 100KL. I have added the water injection to aid in valve cooling. Since adding the water injection the vehicle is running smoother and with better power than before. The vehicle is running better at 19/1 than it was on straight fuel,
What I am coming to after all that is what would be the opinion of those who know better than I if I was to get in touch with Garry of Chemelec to change the settings of his o2 sensor so I could increase the higher end of the o2 sensor to run on maybe 22/1 air fuel ratio.
I am thinking that higher air fuel ration may well be possible seeing that at 19/1 I cannot get this car to ping under any condition.
So I seek your comments.
Regards to all.
Weggl

[readyakira]

[peterZA]

[FlashBang]

[peterZA]

[moses]

[Hybrid]

[BeRational]

On my mustang I have a tuning program and the computer (ECU) does not allow for adjusting the A/F ratio beyond 18:1.

That said, the way that A/F ratio is calculated is by how much fuel the computer calculates went in based on the time the fuel injectors were open. And how much air passed the Air Mass sensor.

The o2 sensors do not detect A/F ratio, they detect Stoichiometric (A complete burn). The O2 sensor feeds back to the ECU with a voltage for how much bellow or above stoichiometric. Then the ECU will add or subtract time that the injectors are open to try to get to the correct ratio.

During "Open loop" Wide open throttle and startup, The ECU has a fuel map table to determine how much fuel should be added. And does not look at the sensors besides the Air Mass. If you can count on the HHO being there those map tables could be adjusted or fuel pressure reduced.

Here is the theory part, that I have not tried yet:
Hypothesis: When adding HHO to the combustion we are still searching for Stoichiometric, therefore the O2 sensors are still working to hit the same value. The ECU should be able to correctly add the gasoline needed to adjust to the blended fuel. The concern is that the ECU has minimum limits built in that will not allow reduce the gasoline injection to a small enough value. In this case turning down the Fuel Pressure would trick the computer into injecting less fuel for the same injector opening time.

[Hybrid]

The Air Mass sensor figures can be overrid with an safc is one.
A 3 bar map sensor reading (mid your inlet mani) can be
wired with the safc & then the throttle body position sensor is
not telling the ecu that you floored it & need more fuel.
You can setup 2 settings in an safc, so you can switch if on HHO.
Your dead times for your injector opening times can be changed
in your eprom. An eprom can have 2 tunes & be switchable also.
There are a few tips BeRational. But dancing is more fun
Cheers !

[mos68x]

A knock/ping will only occur when IGNITION timing is set BTDC. As long as the timing is set at least 15 deg ATDC you will not hear a knock or ping. Preignition/detonation can sound the same but is not from ignition timing, it is from a hot spot in the chamber that ignites the fuel prematurely. With hydroxy you have to set your ignition timing much later (retarded) so that you do not cause the knock/ping. A/F ratios have some effect on the knock/ping if timing is left unaltered, but not as much as timing itself would. You could have the A/F ratio extremely lean and as long as you didn't have any hot spots in the chamber to cause detonation and have the ignition timing set ATDC you would NEVER have a knock/ping...even with water injection.

[Veggibenz]

How about a somewhat metered auxiliary air valve for additional air during low manifold vacuum instead of fussing much with the AFM. A product that comes to mind is the vacuum operated heater valve. This could be simply mounted after the AFM, using a small homemade air filter on one side and an inlet to the snorkel after the AFM. There are many vacuum sources that the vacuum pod could be attached. For instance, on a direct manifold vacuum port controlled by engine temperature. Most vacuum operated heater control valves are about 1/2 inch, which could under basic controls. be what would lean your system enough that the introduction of HHO completes the mixture. This setup could also be your main supply for HHO after determining what conditions HHo should be introduced once you map out your vacuum sources. Remember, there are lots of different vacuum operated controls, controlled by 12v, 1-second, 2- second delay.., vacuum temp controlled valves..... A little imagination could provide a KISS solution. ( Keep It Simple, St____ )
Paul