jplavoie

Hi,

I want to know which engine is best suited for a .40 size profile (Burrito 40). I was thinking a BSE 60L-H or a BSE 76L. What is the difference between these two engine and which one would be the best choice?

Thanks

JPL

bob27s

My Feedback: (19)

Thanks for writing......

The 60L-H engine is a cast-case engine, same internals as the standard 60L engine, provided with an un-tuned light weight muffler and a carb designed for a more linear midrange. Same size and weight (actually lighter with the lite-jett muffler) as an OS46. Works best with 11x5, 11x6, 12x4 or 12.25x3.75 props, similar to a .46 size engine. Designed to run in the 13,000-15,000 peak rpm range..... and if you give up some of that midrange flatness, you can use the jett-stream tuned muffler and it will sing up well above 16,500 rpm. Very versitile, easy to operate.

The 76-L is based on the CL stunt engine, and is designed for big props and low rpm. Available only in the BSE machined crankcase. It is slightly taller cylinder-wise than the 60L, but otherwise fits the same install footprint as most 46-50 engines. Provides "big block" engine power in a .40 size engine. Runs more like a 4c engine. The engine is designed for and provided with an un-tuned lite-jett muffler, and includes a very smooth carb set up for the proper throttle curve. Prop selection should be made to keep the engine between 9,500 and 12,000 peak ground rpm. About 10,500 is our target. Typically a 14x4, 14x4W, 13x6, and even a 14x6 are good choices.

A few photos to give you an idea....

Twist has a 76L engine up front. This is a great application. The full fuselage planes sorta need the big diameter prop.

The Top Cat has a 60L-H engine up front. Owner decided it was more fun with the tuned muffler 12.25 X 3.75 turns 15,000+ peak, and he launches around 14,600 - 14,800 (typical setup, about 500-600 rpm down)

Mo-Jo shown has a 76L up front

SLEdge utilizes a 60L-H engine with the lite muffler.

Red one is my aircraft with 60LH up front, 12.25x3.75 prop ..... although I like flying it with the standard 12x4 - seems smoother. Turns around 14,000 peak. Only reason I do not have my 76L in here is ground clearance for the 14x4, and I sometimes toss the jett-stream muffler with a 10x6 prop.

Green one is a Burrito with 76L power up front, shown with 14x4 on the shaft.

As for engine choice.....
Sorta is up to you.
But for the smaller .40 size profile airframe, I would personally probably go with the 60L-H. Of course, if insain power is the goal, then the 76L is the answer. It is just a smooth, reliable engine - and it seems to take well to 3D flying.

Something to point out... fuel tank location is important. A lot of the profiles have fuel tank located in the wing. Typically this is NOT good unless you have a really good running 4C or a YS with a pressurized system. Take a look at the photos here. On profiles, I prefer to put the tank opposite the engine, as you will see others have done too. Also worth while considering a bubble tank - no worries of fuel foam, no issue with air in the lines - just fuel, and consistant pressure.

Bob

jplavoie

Thank you so much Bob,

sounds like I'll go for the 60L-H. I understand there is no BSE version for this engine, right? It's not that I don't like Jett's cast cases.. but I definetly prefer your BSE cases.

JP

bob27s

My Feedback: (19)

You can get the 60L-H as a BSE .... no issue. Costs a few $$$ more. I just don't think we ever sold one that was not cast case

jplavoie

Hi Bob,

does the BSE engines carry some advantage over the cast case? According to my experience, casting produces more structural defects than machining, but I'm not sure this is an issue with RC engines. Please let me know.

Thanks

JP

bob27s

My Feedback: (19)

The BSE engines sometimes perform slightly better, but it is very hard to quantify. So in general, they both run pretty much the same.