Ignition timing

What's adjusting ingition timing? Ignition timing controls when the spark plugs fire to start the combustion of the fuel in the cylinders of the engine. This is different from adjusting the cam timing (any newbies out there?) By advancing your ignition timing, you make the spark occur ahead of when it does normally, potentially making the engine utilize more of the cumbustion force on it's downward stroke. The benefits of advanced timing include: more free response, better low end torque, and better gas mileage. There might be slight HP gains, but it's most likely negligible. Your engine may also run hotter.

To advance your timing, you need these tools:

12mm ? (torque) wrench
a timing light
wire to short out the ECU

First short out the ECU, look in your (HELM I hope) manual and find the wires you need to short to allow you to adjust the engine. On my car, I needed to pull out the ECU wiring right underneath the glove compartment near the passanger door. You short the connector that has two holes.

Connect the timing light the way described in the instructions. Loosen the distributor cap. With the engine warm and idling, use the timing light to locate the timing marks on the timing belt. There should be four marks. One mark represents top dead center, or when piston number one (the piston farthest from the distributor on my engine) is at the top of its stroke. This mark is colored white. Farther away from this mark should be your important timing marks. Two black marks and one red mark. The red mark should be in between the two black lines. This red line represents the cars factory timing setting. On my car, that is 16 degrees. The other two marks represent the tolerance that the factory suggests not to go beyond. This is +-2 degrees on my car. To advance the timing on my Civic, I slowly turned the top of the distributor toward the back of the car. Watching the timing lights, I stopped rotating the cap when I noticed the timing was at 18 degrees (the black mark farthest away from the white mark).

Tighten the bolts on the distributor cap. Make sure to check the timing after doing this to make sure you didn't change the position of the cap while tightening the bolts. After this, I removed the wire that shorted the ECU, and then I pulled the 7.5A fuse in the hood fuse box (the one nearest the passanger compartment) to reset the ECU. Put the fuse back in after about 10 seconds. You'll need to reset your clock and radio settings.

It's important to realize that these steps are for my engine, the D15B7 engine. You car might be different. Setting up the ECU, the timing gun, and the distributor all should be done with the engine off. When you remove the timing gun, the shorting wire, resetting the ECU, and tighten the distributor cap, make sure the engine is off again. Also keep in mind that if you advance your timing too much, you'll get what is referred to as knocking, or detonation. This is detructive to your engine! To help prevent this you need to run high octane gasoline after you advance your timing. I am not responsible if you damage your car by advancing your timing.



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