Hi Doc I also believe that a 10/6 is too much of a load for the little fs26 and may lead to inflight intermittent surging and a tendency to run too hot.

If you want to run ten inchers then a four or five pitch is a better choice and if the airframe allows it to pick up a little airspeed then 9/5 is a good choice.

Here are a couple of photos of my Oxy Moron which is a Seniorita and serves as a twin and a glider. The original engines were the fs 26's, later a pair of Magnum 30's were tried and the airplane currently has OS .25FX:



John