TD .049 run time

OhBee, what have you got for props? I can send up a couple of three-blade 5x3, and maybe a couple of 2-blade 5x3. I don't have a pile of 6" props, or I'd offer them too.

Each time I took a new bird out, I took a few props on either side of "normal." After a few flights, I'd change the prop and try it again...and again...and again. Until I ran out of props to try, or found a personal preference.

If you way over-prop, worst case is a slow-turning, fuel-sucking, stable flight.
If you way short-prop it, worst case is high rpms from the engine with little thrust.

Either way, I recommend short-tanking it and engaging somebody to time your "seconds per turn." Do two or three quickies excluding the first few spins to come up to speed, and then change props and do it again.

There will be a point where you get good traction for stunts, or good speed (and dizzy)...or hopefully something in between in YOUR sweet spot for your type of flying.

Well, my Scientific P-40 had a 1/2 oz tank feeding the pressure-fed AP .061 for about 2:45 on a 6x3. While it has displacement over the Tee Dee, I bet the Tee Dee would give the AP a good fight.

If you rubber-band the tank to it, you can change on the fly. Considering the impediments you mention, I think you would be best served by that Tee Dee if you de-tune it a bit. Either here, or on StuntHanger someone sleeved the venturi down a bit to soften the engine a bit. Another way to temporarily accomplish this would be to install a Medallion body on that engine.

I would advise use whatever tank is:
On hand no more than 2/3 oz (although I like the 3/8 for you), and
as large as possible without throwing off your CG

And:
Restrict the engine
3-blade 5x3 prop (trade speed for traction)

As long as the tank is rubber mounted and the engine is de-tuned non-destructively, then you can up the game in pieces. Play with props first, then revert to full Tee Dee power.

OhBee, a screen would be a fair thing to try. That may assist with fuel draw at slower speeds. While Tee Dees are neat engines, if the engine will be too much for you, then flying will be a miserable experience.

Gary,
While you did effectively de-tune the engine (which is what OhBee is looking for), the intent of the Medallion body is to increase fuel draw capabilities by restricting the intake. A smaller cross-section throttle port will induce more vacuum signal to the spray bar/NVA. Of course, the smaller intake also throttles the engine down a smidge.

The best part is the better vacuum signal reduces the need for pressurized fuel supply, whether by choking the engine with a screen, or installing the Medallion front end.

I will admit that I don't have a Tee Dee, have never had a Tee Dee, and am making my recommendations based on anecdotal stories of Tee Dees needing pressure.

I think Ron Cribbs or Ken Cook mentioned before that Tee Dees don't need pressure (either here or on StuntHanger). Regardless, I do believe a stock Tee Dee is the wrong engine for the purpose, given OhBee's desires to do only Roundie-Roundie.

OhBee, if I had a spare Medallion, I'd offer to swap at my expense. Alas, I have only two...for a future twin.

Well OhBee,

Then I loosely suggest the biggest tank you can reasonably fit on it. A 1/2 or 2/3 oz tank can always be short-filled as long as you fill at least to the point the fuel feed tube is in fuel while you start her up. I certainly wouldn't go much bigger than that, and really believe a 3/8 tank will get you in the air long enough to wish things would be a bit more sedate...at least until you discover your flying legs again.
Once the plane is flying, the rest of the fuel of a "short-tank" will sling outboard to the tip of the wedge anyway. I still like the idea of interchangable rubberbanded tanks. You'll get to play with CG and times by changing tanks.

I fill my tanks with a 5 cc syringe. The Scientific P-40 needed at least two syringes to ensure fuel draw while on the landing gear (for starting), unless I turned the outboard side down. Then no matter how short a fuel load, it still got picked up. The bonus to short runs is that you have just enough time to think of what to change next without wishing for an excuse to land. You wind up with more, but shorter test flights per outing until you build up to longer flying times with a more sorted-out plane.

I'm dying to see this one completed. The colors are wonderful, and the work is fabulous! I hope to see video.

OhBee, I may have a spare tank or two laying around...post the measurements of yours so we know what you have. I'll check to see if I have moderate steps up from there.

I'll check my stock in the am.