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Discussion Starter #1
HI! Newby here. I have an old ford 302 and need basic info on timing.
Why does the engine speed up when the timing is advanced at idle? My specs say 6btd.
what are the upper limits of timing at idle?
If I advance to 12 btd or 16btd, what will the effects be good or bad?
I read once that you advance until it starts to ping at the upper rpm limit and then back off. True?
I'm not so concerned about upper power as I am from stop to about 30 or 40 mph.
So basically, what is the scoop on timing and what are the effects good or bad of messing with the factory setting?
Thanks!
 

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:D



As the moderator for this forum (General Rodding Tech).....let me be the first to WELCOME you here :welcome:

As for your question..........this is more of a engine question SO I am going to move it there...........so it can be answered better and viewed more.

Glad for you to join us........


:D
 

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302 timing

Not knowing the exact year etc of your 302, I would go with a timing of 10 degrees initial. If you dont run into pinging problems on acceleration with 10 degrees, then you could try bumping up another 2 degrees. 302's run quite well with 10-12 degrees intitial advance. 16 degrees is a little much for your stock engine. The reason your engine picked up RPM, when you advanced the distributor from 6 degrees is because you were putting enough advance in the ignition that the engine was gettting a more complete burn of the fuel air mixture. It takes the fuel air mixture a certain rate of time to burn, so the actual ignition process has to start just before the piston reaches top dead center. Other wise, due to the rotation of the engine as each progressive cylinder fires, the piston is in effect somewhat running ahead of the combustion process, and isnt allowing the combustion process to apply its full pressure on the piston.

If you have automatic transmission, I would, if I were you , do a brake stall on your engine.
This requires putting your transmission in gear and with your foot on the brakes (well pumped up), slowly depress the accelerator. If you get any ignition pinging, adjust your distributor back 1 degree and repeat til the pinging goes away.
 

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Discussion Starter #5
thanks!

Hey! thanks Max Keith for the simple answer to a simple question! I will try what you say. A lot of times on forums, simple questions get blown off as it seems they aren't from one of the "inner circle" and I appreciate you took the time to help me out. I will try your suggestion and see what comes of it and let you know how it works out.
Jim
 

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Philippines Cowboy
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Your "advance 'til it pings" idea goes back to the days of the flatheads. And, it worked pretty well then. You usually ended up with something very close to the ideal for maximum engine output. But, with modern OHV and OHC engines, that isn't always the case. Today, you need to use a bit more care.
 

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finding the spark

Billy shope is correct on having to be more careful, that is why I dont recommend going over 12 degrees initial advance.

Having been dealing with Ford engines of all sizes for the past 40+ years, rest assured, I wouldnt deliberately give you some bumb dope on them. The only time I would recommend using such tricks if I know for sure they are tried and proven to work.

Good luck and happy Fording, Fred.
 

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The factory said 6 btd because

the motor will idle "OK" in any climate/altitude in the world. It is a "compromise" setting also for gas quality around the world.

Welcome and for future questions do give more info about the motor.

Flat tappet 302, a little bit of cam, 87 octane, 9/1 comp, a good setting for on the street is 10deg base, 32max total. Motor should start ok when hot, shouldn't burn "too" lean/hot on the highway in summer.

Do keep and use the vacuum advance, with more timing it smooths out "flat spots" on the road.

11? 12?, you need to go to a "test and tune" day at your local strip. Compare a bunch of 60' times to see if it is going to be worth( probably) buying 89 or 93 octane on the street so it will start when hot etc....
 
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