If Rings Don't Seat:

[ERA Chas]

Don't know for sure but you may have 'low-tension' rings that Ford is so fond of.
'Low-tension' is another term for 'no oil control'.
Maybe you got to go in there if there's no other apparent cause.

[DAVID GAGNARD]

I would change out the present oil to any name brand 10/30 conventional oil, then get the engine and oil fully warmed up to operating temp...
then get out on a deserted road somewhere,go thru the gears normally and when you get to 3rd gear,don't punch it, but accelerate quickly to say 5500 rpms,when you hit 5500 rpms, let off the gas and coast back down to about 2000 rpms,then accelerate back up to 5500 rpms all the while leaving it in 3rd gear......... do this 6 to 10 times in a row and watch your temp gauges....then cruise for a few miles in high gear to let things cool off and repeat one more time.......

if this doesn't work, then I'm afraid you may need to pull the engine down...

BTW: you shouldn't put any synthetic oil in it until it is fully broken in and have at least 500 miles on it.....

David

[jhv48]

Thanks, David,

Thats what I have planned for the next step! Going to try to break in the rings all over again.

And I questioned the change to RP 20w50 XPR after break in. That oil is super clingy and slippery. Hope this works.

[DAVID GAGNARD]

Originally Posted by jhv48

Thanks, David,

Thats what I have planned for the next step! Going to try to break in the rings all over again.

And I questioned the change to RP 20w50 XPR after break in. That oil is super clingy and slippery. Hope this works.

I'd go down to the nearest wally world and get some 10/30 Valvoline or similar oil.........start your car and get it up to operating temp, then shut it down and change the oil and try to re-break it in again.....leave the 10/30 oil in for a few hundred miles and see how it does.....
you have nothing to lose and everything to gain.....

David

[carmine]

Sounds like your running Teflon valve seals.
They are a stiffer seal and don't have good sealing capabilities for the slight side ways motion that a valve has when moving up and down thus seal can create slight gap during side motion and with the higher vacuum conditions at lower rpms (idle and cruising) when throttle plates hardly open allows oil to be sucked through intake valve and mixed with fuel and burned.
You wouldn't notice any oil burning out the tail pipes during higher rpm tromps because throttle plates more open allowing high vacuum conditions to take there effect through the carb.
Chances are you wouldn't notice at low rpm operation either because oil amount leaking is small but continuous and mixing with fuel and keeping valves clean looking.
Have seen this problem many times and it gets compounded even more when running high volume oil pump because more oil being pumped to the top of head and drain holes in head usually haven't been increased to allow this extra oil to be drained back down fast enough thus creating a higher pooling level in the heads which can come up high enough to completely immerse the valve seals in oil.

Solution to this problem is to change the valve seals to Viton valve seals.
These seals are a special rubber that seal and move with the valve sideways motion.
They were developed especially for this problem.