1989 mustang 5.0 stock timing setting

Stock is 10.


Paint the mark on the harmonic balancer with paint -choose 10 degrees BTC or 14 degrees BTC or something else if you have NO2 or other power adder. I try to paint TDC red, 10 degrees BTC white, and 14 degrees BTC blue.

Remove the SPOUT connector (do a search if you want a picture of the SPOUT connector) It is the 2 pin rectangular plug on the distributor wiring harness. Only the EFI Mustang engines have a SPOUT. If yours is not EFI, check for a SPOUT: if you don’t find one, skip any instructions regarding the SPOUT
Warning: there are only two places the SPOUT should be when you time the engine. The first place is in your pocket while you are setting the timing and the second is back in the harness when you finish. The little bugger is too easy to lose and too hard to find a replacement.

Connect timing light up to battery & #1 spark plug.
To time the ignition: remove the SPOUT and use the timing light to check the timing against the marks on the harmonic balancer. Loosen the distributor hold down bolt and turn the distributor slowly until the light and the desired mark on the harmonic balancer line up. Tighten down the distributor hold down bolt and re-install the SPOUT jumper. When you put the SPOUT back in the computer will advance the spark. The timing may move around some with the SPOUT installed.

10 degrees BTC is towards the drivers side marks.

Simplified diagram of what it looks like. Not all the marks are shown for ease of viewing.

ATC ' ' ' ' ' ' ' ' ' '!' ' ' ' ' ' ' ' ' ' BTC
---------------- > Direction of Rotation as viewed standing in front of the engine.

The ' is 2 degrees.
The ! is TDC
The ' is 10 degrees BTC
Set the timing 5 marks BTC. Or if you prefer, 5 marks towards the driver's side.

The HO firing order is 1-3-7-2-6-5-4-8.
Non HO firing order is 1-5-4-2-6-3-7-8