I was just reading the Gremlin 1/2A pattern plane article in the May ’75 issue of Model Builder by Tom Dixon, and it says the plane flies on a Cox “stunt special” engine.  The “stunt special” is a TD .049 with a Babe Bee piston/cylinder and a low compression glow head, a Kirn-Kraft NVA, and turning a Cox 6x4 prop on 5% nitro fuel from a Perfect wedge tank.  Tom says this pulls the 12 ounce model through the entire stunt pattern.  The KK fine needle would be the only thing I would have associated with “performance”.  A low compression head topping a single bypass/no boost cylinder with SPI doesn’t scream “performance”.  5% nitro on a 1/2A doesn’t scream “performance”.  A TD on suction from a standard plumbed wedge tank doesn’t scream performance.  And a Cox 6x4 doesn’t scream “performance” (unless you’re propping for torque).  And we all know Cox TD engines were made to scream.

What exactly am I missing on this?

Sound all wrong to me! I went the other way with a Medallion bottom end and Tee Dee top. 15% Nitro. Great runs!

This is what I’d do.

Go with it as is and just fly on longer lines. You’l love it.

Nothing wrong with the Tee Dee in take system, it is the wild Tee Dee crank timing! A Tee Dee with a Medallion crank shoUld run just fine as a stunt engine, it is just easier to grab the entire Medallion bottom end. (Especially if you work in the factory 🤭)