Is the LA 46 too much engine for a Twister?  The reason I asked is that when I built my Twister, I set it up with the Brodak mount system, but when I tried to fit a Fox 35, I realized I hadn't allowed for the backplate studs being so wide (about 1.5").  The LA 46 fits beautifully; though, and with a tongue muffler, it is only 9oz.  That's only about a half ounce heavier than the Fox with standard muffler.  Any opinions?..........Glen

Is the LA 46 too much engine for a Twister?  The reason I asked is that when I built my Twister, I set it up with the Brodak mount system, but when I tried to fit a Fox 35, I realized I hadn't allowed for the backplate studs being so wide (about 1.5").  The LA 46 fits beautifully; though, and with a tongue muffler, it is only 9oz.  That's only about a half ounce heavier than the Fox with standard muffler.  Any opinions?..........Glen

As long as it balances it will be fine. The engine turns the prop and the prop pulls the plane. Prop (or gear) it accordingly.

I saw a Twister outfitted with an LA46 this past summer. Propped right, it was a mild enough flyer, definitely stunt friendly. Surprised me. Since I'm accustomed to those engines lugging Cardinals, a considerably larger airplane. Legally, a 46 means .018 lines in competition. Sport flyers often fudge on this. Also, I've been to many local contests where line diameter is not checked. La46s are a little easier to rein in for stunt when compared to the 40. Of course many LA40s do fine. If anything the 46 is a tad lighter than the 40. The Twister is on the small side for stunt, by modern standards. ARF Cardinals, P40s, Pathfinder's, etc, have more wing area, probably thicker airfoils. They do all right with fox 35s, apparently 25s can work. I've seen those engines recommended at times for Twisters. 46s have lots more grunt, way more power. But go for it. Use a low pitch prop. The magic prop in Philadelphia is an 11 1/2 x4 apc. Follow the usual drill to keep modern engines from running away. Don't be shy about adding a head gasket. Run good fuel with enough oil (Powermaster 22% (50/50) 5% is what we use for almost everything.) Make sure your muffler flows well.

I think 9000 rpm is too low, it'll want to break hard and runaway. Try about 10,500 or a little over. Don't be shy about adding a head gasket. We usually set the engines by ear. A wet 2 stroke. I know the rpm for 40s is about 10,5000. I've flown plenty of forties. Just getting into the 46. Lots of club members use them. But like I said we set engines by ear, for the most part. The rpm is an estimate. Plenty of guys out there can give you an rpm figure. The LA46 is a very, very popular stunt engine with a no muss no fuss reputation. As soon as the weather breaks I'll put a tac on one of our sweet running 46s. This will be considered a desecration, a violation of tradition. Like using an electric starter. Well, I also use an electric starter. When I muscle myself to the line and flip out a tac, there'll be some verbal abuse.  Yeah! 

Just wrote stuff about using a tongue muffler, to cut weight, well you are using one. So scratch that. Foam wheels can save a half ounce or so, over standard wheels. Why not try it. If you're not using those. A forty-five ounce Twister should be viable, pulled around by an LA 46. Otherwise, if you're confident about the glue joint for your engine mounts, get out a Dremel and grind some wood so the engine can be set back a half inch or so. Mounting points can be redrilled using a hand power drill, if you need to. Not nifty like a drill press. But line her up and let it rip. IT'S A TWISTER.