I just went through my 390 on my f100 and I set the dist to something my engine liked. With the light on it, it seems to be best around 22btdc. Everyone tells me it should be around between 8 and 12btdc. Am I looking at it wrong or is that possible?

 

Are you disconnecting your vacuum advance before setting it? 22 is too high, should be in the range you mentioned.

 

That's a nice looking 68. Here's some timing tips for what it's worth:
Crawl under your truck, get the timing marks on the bottom of the damper where you can read them...clean the area with some steel wool and a rag...run some kids white sidewalk chalk over the marks...makes it real easy to read them with your timing light.
Start the truck and let it warm up to operating temp...attach your timing light and check the timing marks with the dist. vacuum hose connected. Note the number/reading.
Pull the vac hose at the carb and plug that end. This is where you take your base timing reading...curb idle should be at 550 rpm with manual trans. in N. If you have an auto tranny, check the base timing with the truck in Drive and wheels chocked and Parking brake set with headlights on...curb idle should be at 550 rpm. In Park or N with auto tranny it should go up to about 650 rpm and remain steady.
Baseline factory spec timing for 360/390 is 6 degrees BTDC for standard tranny, and 10 degrees for auto tranny. I get good results with mine set at 12-14 degrees BTDC...auto tranny in Drive, wheels locked, vac hose disconnected and plugged. I set mine there and went two sizes smaller on my carb jets because I live at 3500 ft. above sea level. Runs best there and gets decent mileage too.
Carbs are factory jetted for sea level altitude. Holley recommends reducing jet size one or two sizes for every 2000 feet above sea level.
Your truck will run better with the timing advanced...like you said in your post, but this will rob it of acceleration/top end. Plus, if the timing is too far advanced the engine will fire too soon in the piston stroke at speed and wash/burn the oil off the cylinder walls...leading to metal to metal wear and eventual engine failure.
Once you get your timing set to spec, set the curb idle speed. A vacuum gauge is a great tool for tuning, too.

 

I'd be surprised if you could even start the engine @22btdc without some serious starter kickback, perhaps your dampner has slipped giving you a false reading, or your vacuum advance is connected to manifold vacuum pulling in all your vacuum advance at idle (assuming you didn't disconnect it), i find most 390FE's to be happiest @12btdc give or take.

 

That is an awful lot of advance. If true, you could take the top off a piston with preignition on a hot summer day. I suspect that something is wrong with the damper as the guys have suggested.
There are ways to feel out TDC through the plug hole. We can help you, check back. It might be a good idea to check out the timing mark's actual position with respect to the crank.
Semper Fi

 

Thanks for the tips. I didnt have the vacuum advance removed and plugged when I hit it with the light.
Thanks

 

Wiz, still, I don't think you would run well at 22deg advance with the vacuum line in place at idle. The vacuum line to the distributor should hook in above the throttle plate and there is essentially no vacuum at idle. You may have the line hooked below the plate directly into the intake manifold. Check and make sure.