I am new to RC airplanes, and am a bit lost as far aas evaluating engines. I have focused mostly on 2-stroke .40 or .46 engines. I see a lot of information about Brake Horespower (bhp) and would like to know if this is a true indication of the end power of an engine. If not, what should I look for in an engine?

*In my opinion there are 3 good .40ish size engines. The Thunder Tiger 46pro, OS 46fx and ST.45. ST has been a ghost lately so apparently the Magnum is taking its place for a while.
I have all three and happy with them.
*The TT & OS are for the most part ,the same engine all the way around. Now lets use thew 46fx. You install this engine on a trainer like a Sig LT-40. Pulls it around pretty good. Nothing spectacular but good enough for training.
* Now you pull that engine out and put it in a small .40 size warbird like a P-51. Aero dynamics are better and speed is significantly increased.
* Now you take this same engine and put it in a .40 size Shrike or Diamond Dust and your looking at around 125mph. It all comes down to what plane you are going to use. This topic will open up a great can of worms.

Most of the brake horse power values given by the manuufacturers is a whole bunch of useless information.

I don't know where you live or what you have experienced so far, but generally the ball bearing ABC 46's are the better ones as far as hp goes. Some of the leaders, but not all of them, are OS46FX, Thunder Tiger Pro46, Super Tiger GS45, MDS48. GMS47,Tower pro46, Magnum/ASP/SC 46XLS (latest version). Enya CX50, and Irvine 53. These engines have different prices and the quality varies somewhat between them. It's likely that you would be very happy with any of these. They all have about the same power.

The best determination of the best engine would actually be your preference.

Also, You could possibly enjoy a different engine if you became accustomed to it and it served your style properly.

However, the standard of comparison is the OS46FX.

There will be more entries on this thread proclaiming a certain engine junk or that only a certain one is worth considering but the choice is yours.

Good luck,

Jim

BHP is the HP usually with the smallest prop a company can get away with running on an engine, flying the average sport model you'd be better off with an engine that will turn a 12x6 at 10,000 or 11,000 rpm than one which will turn a 10x6 at 17,000. Such an engine would be an Irvine .53 for example, which handles a 12x6 or even a 13x6 quite handily. I mentioned the Irvine because it is the one most often recommended on here as being user friendly, smooth running and not too particular what fuel you run in it.

Thank you for the rapid response! this is what I needed.