Both of my Evolution engines are easy to start. I have run the .45 and .46 a lot. The noticable problem is that once started the crankcases seemed loaded and they wouldn't run smoothly until the throttle was massaged and wide open achieved. This took time.

The .45 is simply a hot engine that puts out a lot of power when the flywheel weight is removed and something along the lines of a 11x7 prop is used. The engine that I have has more than a hundred flights without a deadstick, except for 2 when there was trash in the needle valve. It just wants to run and doesn't care how you run it.

The .46NT replaced an OS .46FX. That replaced a TT Pro .46. I don't recall breaking in the .46NT. I did run it a couple of minutes before putting it on the same plane. I got some comments on my first takeoff run about how much more power the Evo seemed to have over the .46FX. This was with the OS 8 plug and the engine developed more power after a few tanks of fuel.

I'm not a 3D flyer, but there are a lot of Somethin Extras at my club and those guys do hover. The .46NT is on a SE and being that I once flew helicopters I sometimes feel like I should at least give it a try for grins. Before changing from the OS 8 to the Towers plug I could sustain hover power at 75% throttle. It is now less than half throttle with the Towers plug. That is all that changed. Same Omega 15% fuel, same APC 12.25x3.75 prop. I could not take off and pull vertical and accelerate with the #8 but I can now. Well, I did put a Towers muffler on the engine and not on the OS or TT. The Towers plug made much more difference in performance. Yes, I did have to tune the HS needle valve, but I hadn't flown the engine since cold weather and can't comment more on that.

I keep forgetting to drag out the RCMs with the .45 and .46 teardown and review. I think both were by Clarence Lee. I don't recall any comments about lower compressions but I will find them and see. I've searched a couple of other places and compression isn't mentioned. I would be surprised if this were true. These engines are well made, well designed, and a great bargain considering they are chromed. They are not cheap knockoffs.