86-93 5.0L Mustang Ignition Timing: How To

Posted 6/3/2013 by Jonathan McDonald

Need help setting the timing on your 86-93 5.0L Mustang? Watch our how to video and read the article for all the information you need to properly set the timing in your Stang!

FOLLOW: mustang , 79 93 mustang , fox body , video , installation , engine , ignition

Advancing the ignition timing on your Fox Mustang is one of the age old "free" horsepower mods. A timing light, a wrench, and a little bit of time will net you more power. Thats just one reason to adjust your timing. The other is if you've moved your distributor at all. If you have replaced, removed/installed, turned, or twisted your distributor you need to check & possibly adjust your ignition timing!

Checking and adjusting the ignition timing won't take long, but will require you to have a timing light and a specialty distributor wrench or a 1/4" ratchet, long extension, swivel joint, and a 1/2" socket. Before getting started, a good "best practice" is to clean & clearly mark your harmonic balancer as well as the leading edge of the timing pointer (has TIME stamped right next to it).

Each mark represents a 2° increment. Marking 10°, 12°, 14°, and 16° will pretty much cover you. A paint marker or paint touch up pen will get the job done for marking purposes. First off, bring the engine to operating temperature. Turn the engine off, remove the spout connector, and loosen the distributor hold down bolt and clamp just enough that you can twist the distributor with a bit of effort. Connect your timing light to the cylinder #1 spark plug wire. Start your Stang and verify what the base timing is currently set at. If it requires adjustment, turn the distributor until the mark on the balancer lines up with the edge of the pointer. Turn off your car & plug the spout connector back in. Start the engine again & use the timing light to make sure the computer is advancing timing. You'll know because the reading will be significantly more advanced than the base reading & it will be fluctuating. Depending on the range of adjustment made, it may be necessary to adjust your idle speed.

Take your Stang for a test drive & perform a few wide open throttle accelerations. Listen for detonation (sounds like rattling rocks in a plastic cup). If you hear any detonation, back the timing down by 2°. If you hear none on the initial test drive, try advancing another 2° and take another drive. Do this until you detect detonation & then back it down by 2°. Stock timing is 10° advanced, so if you plan on running 87 octane "regular unleaded", we strongly suggest leaving the timing at the stock setting of 10°. If you are running 91 or 93 octane premium unleaded gasoline, start out at 12° or 14° and work up from there. Keep in mind, every combination is different. Even Mustangs with the exact same mods will require different timing settings. Take your time, do it right once, and motor on down the road with more power!

If you need help on replacing your Distributor, check out our How To Install A Mustang Distributor article.




86-93 5.0L Mustang Ignition Timing: How To Tech Info

This Install is intended to help with the following year models:
1986 (86) - 1987 (87) - 1988 (88) - 1989 (89) - 1990 (90) - 1991 (91) - 1992 (92) - 1993 (93)