Is this engine too big?
 

Hi gentleman

I'm going to get a WM Rambler 45 and I have 3 engines:

- OS 40LA (came with the avistar R.I.P)
- SuperTigre G51
- SuperTigre G61

The 40LA might be too small and weak, the G51 might be just fine, but... is the G61 just too big for this ARF??

What do you think?

Joseph

RE: Is this engine too big?
 

I'm running an O.S. 61 in a Giles G202 46 and it's perfect. Moved the rudder servo to the tail and didn't have to add weight or replace rx/bat positions. When you head vertical you'll be glad you put a bigger engine in.

RE: Is this engine too big?
 

Rule of Thumb - You've got a throttle, you can always throttle back!

RE: Is this engine too big?
 

Rule of Thumb - You've got a throttle, you can always throttle back!

RE: Is this engine too big?
 

Thanks for the quick reply guys.

Hey Kurt, that makes a lot of sense, I hope the wood near the tail is stiff enough to handle the servo and won't rip off in flight, anyway if it does, it's just the rudder right? :D

mimoore67:
Well, my main concern is weight, maybe i'll end up with a hot landing airplane since theres some difference in weight between de 51 and the 61. My second main concern is that I don't know if my brains will be able to resist the temptation of going full throttle :)

I used to fly a WM Mentor (with the G51) untill the receiver just stopped working... in the middle of a low "high speed" pass [:@] I think there's a cute little balsa tree growing right now in the point of impact [&o]

Ohh gee, I really liked that plane, it was fast (at least for me, it was my 2º airplane) and I was going to buy another but I don't know, I wanna try something different.

Damn, I must be annoying, i'll shut up now :D

Oh, I thought i'd share this with you, this was the last succesfull flight of the mentor, before it crashed :(

-> http://media.putfile.com/World-Models-Mentor

If anyone has experience with this plane/engine combo i'd like to know about its behaviour

RE: Is this engine too big?
 

You are right to be concerned. There is no such thing as too much power... but there is definately such a thing as too much weight. Don't forget that you will have to carry more fuel for the 61 as well.

Use the 51 and if you want more speed, get an Ultrathrust muffler. For more vertical, use the Ultrathrust with a flat pitch prop.

Jim

RE: Is this engine too big?
 

Thanks Jim, makes perfect sense.

What's the approximate fuel consumption rate for a G61? oz/minute at WOT??

RE: Is this engine too big?
 

I flew this plane for a year with an OS 46 FX, 11X6 APC prop, and it was a great combination. It is a vey "slippery" design, goes fast with not a lot of power required. It will go vertical for any maneuver you want to do. It has retracts and tends to tip forward if you are not careful in ground handling. It does NOT need a big, heavy engine to spoil it's good flight characteristics and make it more nose heavy. I used full throttle only for vertical, most flying was done at about 60% throttle.

Do yourself a favor and do not load this fine model down with excessive power and weight. Your Super Tigre G51 is probably too much engine, but of the three you show, it is by far the best choice.

Enjoy this fine airplane.

RE: Is this engine too big?
 

I had the Rambler 45 and the first engine was a TT61 2C, then I had an SC46, the plane flew much better with the smaller engine. The increased wing loading was not all that fun. With a ST51 you will have sufficient power to enjoy aerobatic on this plane. There is no real need for the ST61. Go with what Jim says ... the ST51.

RE: Is this engine too big?
 

I'm a believer now :D

Thanks guys, i'll go for the 51

Cheers and thanks