That combo is a 2.01 final drive ratio. I ran that same-ish final drive with The GVOD, plus the 833od, plus 3.55s, and yes I got fantastic fuel mileage with a 223@.050 cam. But Just remember to ease into overdrive. That gear only has 18 teeth and in no way compares in strength to the rest of the 833 gears. I unzipped the teeth on two of those, one with my 367HO, and one with my stock long-block, 1973 teener.
3.09x2.76=8.528, and 8.528/2.66=3.206, so it takes of like the regular A833 would with 3.23s. I didn't think it was too bad either, but that 223* cam made wicked torque at 10.9 compression ratio.
I told the balance shop, that I didn't care about vibration below 3000, I just wanted the engine to survive at shift-rpm.
I only shifted the Mopar 292/108 cam at 7200. The 223 cam usually got shifted quite a bit lower, but I often held it to 7000 in the first two gears. And the current 230* cam almost always gets held to 7000. Why you ask? Just cuz it goes there, and the power has not rolled off even noticeable yet in first-over @65=6900, cuz the tires are still spinning, and cuz it just sounds so darn awesome when the tach is pegged at 7000 for 5 to 6 seconds. Call me crazy, I'm OK with that; she's held together since 1999, and over 100,000 miles so whatever the balance shop did, it mustabin right.