Try using one if you want to then. One way to do it would be with a potentiometer. Both of these are for 2g's, but you just need the correct wire on the ecu (looks like pin 16 to me)
http://vfaq.com/mods/ecu-harness-1G.html
This will give you an idea of what to do. Remember use your logger to watch knock!:
http://rds.yahoo.com/S=2766679/K=dsm...2gdefencer.htm
off of magnus's website:
http://www.magnusmotorsports.com/1g2g.asp
(copied from the link above)
The value that would be the easiest to change would be the barometric pressure sensor. We’re going to add resistance to this value so that the ECU will see less barometric pressure than what there really is. This will also lean the car out so you should see a performance increase as well. Depending on the car and altitude you might need to add more fuel with an AFC.
So let’s get started, Parts needed:
A 10K potentiometer (although a 5K would probably do just fine). These are available at any electronics store, if you go to Radio Shack ask for a volume control knob because they don’t know what a potentiometer is
Wire strippers
Soldering iron
Step 1: Remove the access panel on the driver’s side of the center console. You should now see four plugs with a ton of wires going to them.
Step 2: Pull out the top plug, it’ll be the one that’s the hardest to reach. Locate wire #85. It’s orange with a white stripe. <- yours is different!
Step 3: Cut the orange wire in half. Solder one end of the wire to the center peg of your potentiometer. Solder the other end to either the left or right leg, it doesn’t matter which. Turn your potentiometer all the way counter-clockwise.
Step 4: Plug the harness back in and start up the car. It should sound like it did before you did any modifications. If the idle is choppy or the car won’t run you turned your potentiometer the wrong way.
Step 5: Add resistance to the barometric pressure sensor by slowly turning the knob on the potentiometer.
That’s it, special thanks to Marco for pioneering this mod and to all the guys on the DSM1Gina2G Yahoo group for all the discussion, ideas, etc.
-Blake Heisler