Timing light question

[dulcimerbob]

How do I connect a timing light to my 76 Spider ?

[SLOSpider]

You just need to find a good hot wire, I use a small screwdriver pressed into on of the relay location ( relay has been taken out of the smog one) then hook my positive clamp to the screwdriver, ground the other end and connect your timing light to number 4 (matt corrected)plug wire. If you have dual stock points its a bit more process involving jumpering the relay to check start up points at 10 deg and running points at 0. Some people, like myself, run the single points set to 10 deg and call it good.

[manoa matt]

Fiat engines are timed off the #4 plug wire.

A good source for power for the light is the stud on the back of the alternator, and ground clamp attached to the ground pod at the driver's side fender

[wachuko]

Fiat engines are timed off the #4 plug wire.

A good source for power for the light is the stud on the back of the alternator, and ground clamp attached to the ground pod at the driver's side fender

Note to self... must go back and check timing... I was doing it out of plug wire #1 ...

[ventura ace]

For dynamic timing (setting your distributor advance while the engine is running), you may use either #1 or #4, it doesn't make any difference. Both #1 and #4 pistons move up and down at exactly the same time, and they're both connected to the crankshaft exactly the same way. The timing mark is on the crankshaft pulley, and your timing light is a strobe that is blinking to show you the mark on the pulley in relation to a reference pointer. If you're not convinced then check your timing with #4 and check it again with #1, then you'll be convinced that the result is the same.

On the other hand, for initial positioning of the distributor rotor in relation to the rest of the TDC timing marks, we're talking about #4. With the cam shaft pointers on their reference mark and the cranshaft at its TDC reference mark, the dizzy rotor needs to be pointed toward the #4 contact inside the dizzy cap.

Alvon

[dulcimerbob]

Thanks , not used to having battery in the trunk

[kilrwail]

For dynamic timing (setting your distributor advance while the engine is running), you may use either #1 or #4, it doesn't make any difference.
Alvon

Alvon - Thanks for posting that. I've been using a light on cylinder #1 for a lo-o-o-ng time, with no ill effect. All this stuff about using #4 might have confused some folks.