Hi All

I have been mulling over the engine choice for my mustang. I am installing retracts, flaps and covering with monocote. I did replace the 1/16 sheeting to 3/32 to increase strength. From what I have read the 120 4C is alittle too much engine. I am kind of split between the Saito 1.00 and the OS 91FX two stroke. I know the two stroke has huge power compaired to the Saito but I like the sound of the four stroke. The thing I am a little worried about is the power to weight ratio, is the Saito strong enough?

Can I install the OS 91FX inverted with the slimline inverted pitts muffler, has any one done this? I wanted to do the same with the Saito 1.00, inverted with the slimline pitts inverted.

I am esimating my final weight to in the 8 to 9 lb range. I am not really sure on the final weight but it looks to be coming in at the suggested range.

Thanks for any advice.
Victor55ca

Hey, I just got my kit in the mail. Have you thought about the YS 1.10? This is what I plan to install in mine. Plenty power, lighter weight than the OS 1.20 . Just a thought.

Adam

The YS 110 is the best engine for this plane or for any other TF .60 size warbirds for that matter. This engine is compact, powerful, and reliable.







By the way, your final weight will be more than 10 lbs. My H9 Mustang ARF is already 9 lbs, and that plane is built very light.

That is a very impresive tolerance between your cowl and spinner.

It's around 1/16" of clearance, which is more than enough. The spinner backplate never rubs against the front of the cowl at any engine rpm.

I used a Satio 150 and it was a bit much, and it was one hell of a performer! I liked the fact that I could use a larger prop and manage the power setting with the throttle. Personally I think the Saito 1.00 would be enough. The Satio 1.50 I used balanced perfectly - no weight anywhere! My bird was an 8 channel and weighed just over 12 lbs. With flaps it landed fine.

My plane also balanced perfectly without any extra weight added. Total dry weight was 11 lbs 13.6 oz.

By the way, here she is on the balancing stand:

I am running a Saito 100 on mine and had to add 1.5 oz. of tail weight, all up weight is 9-1/4 pds.

Richard, it looks like your balance point is just under the retract from that angle, which would be forward of the recommended 3-7/8" at the LE break. ?

My balance point is actually slightly behind the retracts. It's 3-3/4" at the LE break, which is 1/8" forward of the recommended location.

Victor, i used a Saito 100 inverted with the 90 degree connection and a flex pipe that I ordered from Horizon. A little bit of the Valve covers come out of the cowling and then the exit of the flex pipe was just forward of the fire wall. Worked well and I didn't maul the cowling. Be sure to run fat as hell. I stalled just after take off about 500 yards out and 400 ft of altitude and couldn't get it back. Even after making a flat turn then pushing the nose down I could keep the airspeed up and it had the flight characteristics of a brick. I probably should have kept going straight and crossed my fingers.

I had plenty of power with the engine. Lifted right off the ground after about a 50 foot roll out. Mine weighed near 12 lbs.

I would just use the saito 1.20 and mount it inverted. I am running a total of 8 saitos and they are extremely reliable. The power will not be excessive in a 9# bird. Just my $.02 of info.. Jim

(If I build this bird it will get the 1.2 4 stroker.)