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1989se-i
10-02-2002, 10:37 AM
I got an 89 sei (FI). Is there anyway to adjust the air-fuel ratio? Im trying to get more power and more unburned fuel in my exhaust..... for certain things...:D

Would adjusting the idle speed kick up my af ratio?
AZmike
10-02-2002, 10:40 AM
Your computer automatically does your air-fuel ratios for you. Unless you want to change your computer or mess with the sensors to try and trick it you're stuck.
ACCORD EX
10-02-2002, 10:58 AM
that's why i like carb ! you can fuck with it as you like ! then it fucks you back ! :D

MIKE
PhydeauX
10-02-2002, 11:57 AM
You can get a fpr and turn up the pressure. I've also hear of people putting a pot inline with their intake air temp sensor to fool the engine into thinking the air is colder so it richens the mixture to compensate.

andy
1989se-i
10-02-2002, 12:57 PM
Phy: By pot you mean Potentimeter, right?
That sounds intersesting. The more resistance, the colder it thinks the mixture is? Can you explain this a little more, it sounds intruiging. :p
PhydeauX
10-02-2002, 03:55 PM
You basically just explained it. I used to know of a how to for doing it on toyotas, but I've lost the link long ago. You need to know how much the resistance of the sensor changes with the temprature and then use a pot that is going to give a decent amount of fine tuning with out giving some outlandish values.

andy
1989se-i
10-02-2002, 03:59 PM
Sweet. Should i put the pot on the neg or pos wire? Also, where is the sensor located? :-/
Mantis88LX
10-02-2002, 04:03 PM
pot :bh: :D
A20A1
10-02-2002, 04:41 PM
11:1 to 14:1 (AIR:FUEL)
1989se-i
10-02-2002, 04:48 PM
Will I be able to notice a difference in the way the engine is running when i adjust the pot?
1989se-i
10-02-2002, 04:49 PM
...Does the fuel increase as resistance increases, or does it decrease as resistance increases?
This is gonna be cool :D
BoredRec
10-02-2002, 06:03 PM
If you can trick out the ECT sensor you'll get the same results. The colder the ECU thinks the coolant is, the richer its mixture. Of course, you won't be able to pass smog and would have shitty gas mileage.
1988starter
10-02-2002, 06:15 PM
The sensor is on the right side of the throttlebody facing the back of the car has 2 wires you can also use some regular resistors. Basicaly it acticates the vacume advance I think the lower the resistance the more fuel dumped in. try it.
1989se-i
10-02-2002, 06:43 PM
What if i took the sensor out... and put it somewhere hot in the engine bay?
PhydeauX
10-02-2002, 06:53 PM
My bad, I was confuseing 2 diferent mods. Here is a link to the one I was thinking of http://www.gunter.ws/toyotaefimod.html. It uses the water temp sensor with the pot inline. The other one you replace the intake air sensor with a pot and adjust the mixture manualy. You have to readjust it when the weather changes. Here is the link to that one http://www.alltrac.net/mods/AirTempMod.html. They don't use a pot in their instructions, but I have seen others that do.

andy
1989se-i
10-02-2002, 07:33 PM
COOL thanks dude
1989se-i
10-02-2002, 07:37 PM
Will that fuck me over if i have it set wrong?
rallyeNate
10-02-2002, 08:48 PM
just adding more fuel wont give you more power unless you need it, example took a friends car in to get tuned dynotuned (after adding an ATI Pro Charger) and by LEANING out the fmu he gained 40 more hores at the wheels. to properly adjust afr you need a wideband o2 sensor. but if your hell bent on flooding your cylenders with gas, unplug or o2 sensors and advance the piss out of the disturtor and run 92+OCTANE. unless you add a adjustable fuel pressure regulator or a piggy back fuel computer, you wont be able to adjust the afr.
1989se-i
10-03-2002, 10:28 AM
Maybe i should get an indpependent fuel management dealy. Anyone know the price on these, andif there are any for/thatll fit on 3g's?
PhydeauX
10-03-2002, 02:43 PM
I think the cheapest aftermarket by far is the Mega Squirt (http://www.bgsoflex.com/megasquirt.html). Its a kit you have to put together yourself though. The SDS (http://www.sdsefi.com/) EM4-D will do it and runs about $785. You don't need a laptop to program the SDS. Haltech (http://www.haltech.com/) makes one, but I don't know the modle number. I believe that Justin (88turboaccord) is useing one. There are problaby others. You could also get in touch with funstick about getting a modified gm ecu setup. If you're really serious about an aftermarket ecu then you might as well get one that does spark too. But if the mods that you list in your sig are all that you have done then you don't really need one yet.

andy
1989se-i
10-03-2002, 05:42 PM
Oh, i have another mod: white door vent thingies.. :p