I just bought a 75 F250 ranger XLT with a 390 and A/C but the labels for engine tuning are missing (shocker). Can someone tell me what the factory timing should be?

Thanks for your help

 

All I have is non-California, from a '79 Motor's truck repair manual.

.044 spark plug gap, 6 degrees BTDC (after removing vacuum advance hose and plugging it) and 650RPMs in drive with an automatic.

I'd think in a truck 390, you could get a few more degrees advance out of it with good gas.

 

First thing you should do is go to your local autoparts store and get a book on your truck they range from 18-30 dallors and worth every cent.

 

Agreed.

The book says "Refer to label under the hood"

 

Now that's just too funny...

 

ROFLMAO, MAN THAT SUCKS omg has chiltons and haynes become that sorry, that is sad. Sorry man. Try checking ebay for the actual shop manual.

 

By the way, did ANYONE read post # 2 ?

 

I did...THANK YOU!

 

This was copied from an earlier post I made. By the way, a 4 barrel 390 is not suppose to be an option in 1974, but this truck has an 8/74 manufacture date on the door post. The 4V 390 was an option starting in 1975, supposedly. The VIN does have the "M" engine code, which was not for 1974, but did exist in 1975. I think the new model year for cars and trucks in that era was started in September. I believe this was an non California truck.
This is a lot of initial advance. obviously, it your engine knocks at this setting, retard the timing

I have a 1974 F-250, 4v 390 combo in my truck, also. Here is what the sticker on the valve cover says: 390 cid July 1974, Spark plug BRF-42, Gap .032-.036, point gap .017, dwell 24-30 degrees. Timing 16 degrees BTDC, Vacuum hose disconnected and plugged, at idle, 650 rpm in drive, CO 1% max.
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Thank you...Good info.

It sounds like your motor may be from a 74 or 75. I guess if i set it at 16 and it pings, then that is wrong for this motor.

Is the best advice trial and error??