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Flat Ernie
01-10-2007, 08:43 PM
Looking at my manual & my pretty flashing timing light, I see the following marks on my pulley:

U.D.C. I IGN. IN.OP. I

My manual tells me to set the timing to the first line after IGN. (before IN.OP. I)

I can do that, but what is it? What do those marks mean? How many degrees before or after? Anyone got any correlation for these? Also, where do these engines "like" to run (for example, most Small Block F**d engines are supposed to be 4* or 6* BTDC, but I find they like to run 10-12* BTDC).

This is on my '53 Commander Coupe w/later full-flow 289, R1/R2 cam, 4bbl carb & dual exhaust.

Daddy always said, if yer gonna be dumb, you gotta be tough & I'm one tough sumbitch!

GTtim
01-10-2007, 10:15 PM
Ernie, the line closest to UDC is top dead center. The line closest to IGN is the 4 degree before top dead center mark. Most people find that these engines do well in the 8 degree before range with some doing okay up to about 12. As long as it doesn't ping or fight the starter when turning over, you should be good to go.


Tim K.
'64 R2 GT Hawk

Flat Ernie
01-11-2007, 12:39 AM
quote:Originally posted by GTtim

Ernie, the line closest to UDC is top dead center. The line closest to IGN is the 4 degree before top dead center mark. Most people find that these engines do well in the 8 degree before range with some doing okay up to about 12. As long as it doesn't ping or fight the starter when turning over, you should be good to go.

Thanks, Tim! I bumped it up a bit & figured as long as it wasn't pinging I was OK - nice to get the reassurance when you're new. :D

Daddy always said, if yer gonna be dumb, you gotta be tough & I'm one tough sumbitch!

John Kirchhoff
01-11-2007, 11:19 AM
I fine tuned my timing with a vacuum gauge and it ended up being considerably ahead of the ign mark. I attribute some of that to wear on the gears that turn the distributor.