What should my timing be set at?

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york0060

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Jun 2, 2015
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Location
missouri
My Car
1973 Mach 1 351C 2v, Auto
I am trying to find out what the timing should be set at on my 73, 351 Cleveland 2V,(stock motor). All my shop books says to refer to my valve cover sticker, but it is gone. Thanks for any help.

 
That's what I originally thought as well, but after reading some of the threads on distributors and tuning, I've discovered that my '71 is much happier with the timing set (without vacuum) at 16* BTDC. I'm running vacuum advance (not mechanical), for a total timing of something like 36* when higher up in the RPM range.

This is the thread where I learned the most: http://www.7173mustangs.com/thread-timing-advance?highlight=duraspark

Hope that helps.

 
That's what I originally thought as well, but after reading some of the threads on distributors and tuning, I've discovered that my '71 is much happier with the timing set (without vacuum) at 16* BTDC. I'm running vacuum advance (not mechanical), for a total timing of something like 36* when higher up in the RPM range.

This is the thread where I learned the most: http://www.7173mustangs.com/thread-timing-advance?highlight=duraspark

Hope that helps.
I saw that the 351C 4V version was listed at 16* BTDC. I am running 14* right now with 34* at 2500 rpm with my 4V motor. I have been contemplating trying 16* though to see how it runs at that timing setting.

Eric, what's your compression, that may be the diff with the 1973 2V motor and the cam timing changes for emissions for that year.

 
Because you have a stock "smogged" engine it won't react the same as earlier engines. I would start with 6° BTDC and see how it runs and make sure it doesn't ping. If everything is OK I would advance it a couple of degrees at a time and try it again. If it doesn't run alright retard it a couple of degrees at a time until it does.

 
I am trying to find out what the timing should be set at on my 73, 351 Cleveland 2V,(stock motor). All my shop books says to refer to my valve cover sticker, but it is gone. Thanks for any help.
I just set mine this weekend, the engine is stock other than the new ignition and it has all the smog equip still. I added a pertronix drop in ignition and the timing was completely off afterwards. I set it at 10 degrees idle (with the vacuum plugged off) and then it was around 37 degrees at high rpm. Runs like a champ now!

 
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I saw that the 351C 4V version was listed at 16* BTDC. I am running 14* right now with 34* at 2500 rpm with my 4V motor. I have been contemplating trying 16* though to see how it runs at that timing setting.

Eric, what's your compression, that may be the diff with the 1973 2V motor and the cam timing changes for emissions for that year.
Mine's originally a 2V, but now it's running 9.5:1 with lots of "go faster goodies," so there's not all that much "original" left in my engine. :cool:

 
Per the sticker on my valve cover. 6 degrees BTDC. 73 351c 2v.
Thanks for your help, that's what I assumed but wanted to make sure.

 
The 6* was determined by Ford to be the best all-around initial timing, considering altitudes (sea level to 5000+ feet), and geographic variations (desert to near-arctic conditions), as well as a nice smooth idle. As hot-rodders have found out a long time ago, the engines are usually much happier with more initial timing and come with better gas mileage. Just don't over-do it, as too much initial timing can result in detonation/spark knock.

 
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