Just came across the Aquacraft .46 BB made for airboats but can be used for airplanes.
Distributed by Hobbico.

I saw it on sale at Tower for like $89
What caught my attention was the specs. Almost identical to the O.S. 50sx and weighs 3oz more.

It's not under the airplane motor section, it was under daily sale and marine engines.

Sounds awsome, I bought 2! lol

Anyone else got one?

Its the same engine as the Tower 46 except its blue and not purple. It also says Hobbico on the side instead of Tower. The GMS 47 is also very simular except it has a slightly larger bore. They are all made by GMS.

It'll scream.

Enjoy,

Jim

according to the specs it puts out more horsepower than the tower or gms.
1.75 as compared to 1.4 by the others

Tower 46 Specs pasted from the Tower web site:

Displacement: 7.5cc (.455 cu in)
Bore: 22mm (.866")
Stoke: 19.6mm (.772")
Horsepower: 1.75 BHP at 16,000 RPM
Weight: 475g (16.9 oz) (with Muffler)
Length: 83mm (3-1/4") From Backplate to Front of Drive Washer
17.55mm (11/16") Front to Rear Mounting Hole Centers
Width: 35.4mm (1.39") Width Neglecting Engine Mounting Flanges
44mm (1.73") Side to Side Mounting Hole Centers
Height: 89mm (3-1/2")
Muffler Length: 171mm (6-3/4")(Overall)
Muffler Diameter: 40mm (1-9/16")
Crankshaft Thread Size: 1/4-28
Recommended Props: Break In: 10X7
Trainer and Sport Models: 10X6, 10x7, 10x8, 11x6
Scale Models: 10X6, 10x7, 11x6, 11x7
Operating RPM Range: 2,500 - 16,000 RPM

The blinking smiley faces are not mine. They must be the result of a formatting problem?
Enjoy,

Jim

It looks like the same blue head as on the new Magnum .52.

your right, it's exactly the same as Tower, but look at the specs on the gms .47
SPECS: Displacement: .47 ci (7.72 cc)
Bore: 22.4mm
Stroke: 19.6mm
Output: 1.47 BHP at 15,000 RPM
Practical range: 2,000 - 16,000 RPM
Weight: 475g (with muffler)

I thought they were the same?


Also looking at the specs on the th .46 and the hobbico .46, why would anyone pay twice as much for the O.S. 50sx when it only puts out 1.8hp over the hobbico and th's 1.75?
Crazy

The horsepower ratings that marketers placed on engines only enable certain bragging rights to the seller and mean almost nothing in real practical use on a model airplane. If you'll notice, the rpm's given are usually way beyond any possible use. The reason for the difference between the two engines is that the Hobbico and Tower 46 are rated at 16000 rpm whereby the GMS 47 is rated at 15000 rpm.

The Magnum XLS 52 has a blue head very much like the Hobbico but the ports in the sleeve on this Magnum are placed half way between being a side exhaust and a rear exhaust engine. The exhaust stack sticks out in the pure side exhaust fashion though.

Enjoy,

Jim

I sure wouldn't base my engine purchases based on horsepower ratings.
As mentioned before, these ratings have litttle to do with the real world
usage. I'm not knocking the Hobbico .46, but just try getting it to turn
16k rpm to reach that 1.75 hp.
Anywho, good luck with it.
Jerry

A few guys at our field have TH .46's
I haven't seen anyone have a problem with them and they get gobs of power out of them.
One guy had one on a Venus 40, man that thing would smoke.

Shok-
You're missing the point. Nobody's saying the engine won't scream. They're saying the hp claims are bogus, and they are. I promise you that the O.S. 50 would pull your plane better than the .46. I'll give you an example: I bought an Enya 50CX to power a GP Super Decathalon. Then on my next project (an RV-4) I bought the OS .46FX. I bought the OS because the claimed hp were more than the Enya claimed. Yet the Enya can turn a 12X6 with authority while the OS is more comfortable with an 11X6. The manufacturer's trump up the hp claims to sell more engines. They're basically putting a flat stick on for a prop and seeing how many rpm's they can get. The higher the rpm's the more hp they can claim because hp is a function of velocity. Since you don't, however, fly your plan with a stick for a prop, the hp claims amount to nothing.

I hear ya.
I always spin my engines way up anyway with a small prop.

I run a 9x7 on my Rossi .53, you should hear that thing howl. And it pulls an f-20 off the ground in about 20ft.

I starting to believe that the rated HP. figures and high RPM figures
are also alighned with what the engine is capable of turning (safely)
from a mechanical stand point, and is a GUIDELINE for a maximum RPM
figure.

Note:....this is only my guess.

As an example....a Rossi .45 is "rated" at 16K. Propped and piped, it will
in fact turn 16K (even higher) all day long, even with low nitro.

My new ASP .91 2-stroke is rated at 2 to 9000 rpms.This engine, of course
has twice the displacement as the .45. I think they are saying....they don't
want the engine spinning faster than 9K....that's what it is rated at.

See my point ? They are not rating the motor at some rediculous 14, 15
or 16 thousand revs. On the other hand, the the .50's sized engines we
are talking about....if propped down to a racing prop (not a toothpick) and
piped with a tuned or high performance pipe, and an extra dash of nitro....
will in fact turn 16K or more, no problem. They'll turn 14 bone stock with
the recommended "sport prop".

So basically....the rated RPM and HP figures are given for a full bore....running
it at the limit scenerio....not Joe Blowe.

Dave.

Shok, let us know how the engine runs, once you break it inn!

will do, I'm mounting to my Kangke F-20 testbed this week