Manually Control Air/Fuel Intake Values.

is there away i can control how much fuel goes into my engine with like a flip of a switch? (or turn of a dial?) same for the air... i dont think it will be posible to do with the air, i just wanna be able to put out the power when i need it but for bumper to bumper city driving i think i would much rather have the gas millage... im just wondering if maybe someone has heard of this being done before? i wanna be able to change it on the fly so this way when im crusing i can set it for low and then when someone pulls up along side i turn the dial and bye bye... i donno any info would be great.

variable/adjustable spark curve ignition timing would be about it.

That short of bottle feeding.

variable/adjustable spark curve ignition timing would be about it.

That short of bottle feeding.

is it possible to control it from the cab of the car?

I know MSD makes a dist. that has the adj. "screws" on it, but I think they also make a control box to do the same?

I know MSD makes a dist. that has the adj. "screws" on it, but I think they also make a control box to do the same?

i donno, all i know is im open to all ideas...

well, you control the air that goes into your engine with the throttle, so thats already done for you. as far as your fuel curve, you can get the software to put on a laptop and custom burn your prom from the driver seat and have the same thing. but no, with a computer controlled car there is no way to turn a dial and change the fuel air curves, because its constantly changing with engine speed and load. the only thing i could think would be to somehow wire two PROM chips into the mount, have one programmed to be lean for best fuel economy, and the other rich for better performance, and have them on a toggle switch.

89 wouldn't that be the same thing as cotrol box?

I'll have to look it up, but I could sear I saw one out there that when selected, worked like a "by-pass" if you will, over the stock ecm?

it might be out there, ive never seen it.

well, you control the air that goes into your engine with the throttle, so thats already done for you. as far as your fuel curve, you can get the software to put on a laptop and custom burn your prom from the driver seat and have the same thing. but no, with a computer controlled car there is no way to turn a dial and change the fuel air curves, because its constantly changing with engine speed and load. the only thing i could think would be to somehow wire two PROM chips into the mount, have one programmed to be lean for best fuel economy, and the other rich for better performance, and have them on a toggle switch.

lol, first im gonna wait to see what everyone else posts and if this is still one of the better ideas im gonna work with this... and im guesing air auto adjusts?

I't the other way around. They key is the ignition system, how fast and complete you can burn the air fuel, the more volume you can push, barring exhaust system restrictions, the wider open the throttle would be letting in more air to get to 14/7:1, in EFI land anyways. Carbs you could be a little less precise.

The technology is there, the CART and IRL cars have a system that allows the driver to choose the air/fuel mixture with the push of a button.

I guess it's all on the ECM programing.

Would be kool to know how the system works

btw, im asking for an ls* engine set up, not sure if you need to know that or not, but now you guys know

Hm, I need to get a laptop.

I have seen this done on the rice cars that had custom turbo set ups put on them. They got perfomance computers and programmed with a laptop+special software. They make the system go richer.
But its still done by the computer not the driver.All you need is to have the car run more efficently and your imput isnt needed here.(good on gas at lower RPM). Check with perfomance shops-they can make your car run with less gas most of the time crusing and when needed kick anyones ass too.Its expensive and will be equall to the annual fuel savings!

I have seen this done on the rice cars that had custom turbo set ups put on them. They got perfomance computers and programmed with a laptop+special software. They make the system go richer.
But its still done by the computer not the driver.All you need is to have the car run more efficently and your imput isnt needed here.(good on gas at lower RPM). Check with perfomance shops-they can make your car run with less gas most of the time crusing and when needed kick anyones ass too.Its expensive and will be equall to the annual fuel savings!

I'd be nervous of a lean knock as result shoudl something get out of whack.

the director where I work has a WRX and he has a 2 stage ecm... basically another ECM wired into the original ECM. the 2nd one is calibrated for performance. when he flips the switch you can see the additional smoke from the exhaust because it runs lean. flip it again and he's back to the original ecm. this is more benficial for him because he has a turbo and he has increased the boost to 16lbs.... and he has a free-flowing exhaust.

on a naturally aspirated 3.1 i don't think the slight gains are significant enought to justify the expense. I say forget about it and use laughing gas if you want a "performance switch."

the director where I work has a WRX and he has a 2 stage ecm... basically another ECM wired into the original ECM. the 2nd one is calibrated for performance. when he flips the switch you can see the additional smoke from the exhaust because it runs lean. flip it again and he's back to the original ecm. this is more benficial for him because he has a turbo and he has increased the boost to 16lbs.... and he has a free-flowing exhaust.

on a naturally aspirated 3.1 i don't think the slight gains are significant enought to justify the expense. I say forget about it and use laughing gas if you want a "performance switch."


who the hell is talking about a 3.1? we are talking about ls* engines.

whoops... brain glitch. nobody mentioned engine size... so I mistakenly assumed we were talking about the 3.1 i read about in another thread. i didn't catch my mistake.

but even still, optimizing your A/F ratio will make your engine run smoother... but if you go to far and run lean, you will lose power. without some mode of adding more air along with the fuel (i.e. forced induction, nitrous) I don't see a significant gain.

whoops... brain glitch. nobody mentioned engine size... so I mistakenly assumed we were talking about the 3.1 i read about in another thread. i didn't catch my mistake.

but even still, optimizing your A/F ratio will make your engine run smoother... but if you go to far and run lean, you will lose power. without some mode of adding more air along with the fuel (i.e. forced induction, nitrous) I don't see a significant gain.

i did mention that it was ls* engines up above, about 2 posts before you said something about 3.1. also it will be forced induction, turbo... but the problem is if im pushing 600+ hp to the wheels (i can see this happening, maybe) i want to be able to lower the air / fuel intake levels so that when im sitting in bumper to bumper traffic i dont run out of gas. but i also wanna be able to crank it back up when i need it... lol, like am i about to race? crank that shit up, am i just out crusing? crank it down.

i had a carbed car before and I leaned the Q-jet so much for emissions that it was hard to run the car while the engine was cold, but then fine (no lean knock and it had power too)
305 Cutlass Supreme,stock rebuilt Q-jet
My fuel estimates: lean 18liter/100km
poor perfomance

normal (a bit rich) 25Liter/100km
fast
see the difference now
So when you rebuild the carb think economy too

I'll try to remember to ask him how his works. He has an electronic blow-off valve that changes the max level of boost and fuel map when he flips the switch, or he just runs lean without changing the level of boost when he turns the switch off.
I'll ask him.

Any real performance shop that programs ECMs should be aware of this process. they should be able to tell you exactly what you need. Essentially all it is, is a blow-off valve that holds the pressure to a higher limit and a piggy-back/stage II ecm.