Hi all,

I'm trying to find the most powerful 46 size engine and so far, it looks like
Tower Hobbies 46 is the one.

Tower Hobbies 46 = 1.75 BHP at 16,000 RPM
Thunder Tiger 46 = 1.43 BHP at 16,000 RPM
SuperTigre GS-45 = 1.45 BHP at 16,000 RPM
O.S. .46 LA = 1.2 BHP at 15,000 rpm
O.S. .46 FX = 1.62 BHP at 16,000 rpm
O.S. .46 AX ABL = 1.65ps at 16000 rpm
GMS .47 = 1.47 BHP at 16,000 RPM
Magnum XLS-46 = ??
Fox .46 = ??
EVOLUTION 46 NT = ??

IRVINE 53 = ?
MAGNUM XLS 52A = ?


Could you guys help me out to find out the most powerful 46 size engine ?
Thanks !!

Jake.

Jake,

You may as well throw all this horsepower stuff out the window? It means very little to anyone that plays around with engines all the time. Most often, the figures are at rpm's that are not practical for use. To get 16,000 rpm from a Tower 46 would be to run a 8-6 prop on it and your static thrust would be zilch. My father-in-law always said that figures don't lie but liers figure. The HP ratings are just advertising hype.

The only real comparison would be to run 6 each of all these engines with the same prop (11-6) and fuel on the same day and pick the best runs of each brand...

Right now, the most powerful engine seems to be the AX. All of the ball bearing type engines you listed are very close in power. You would be very happy with any of them. The OS-LA series is not ball bearing and has much less power than the other engines. It is more of an engine for a smaller trainer or a very light weight special purpose plane.

Enjoy,

Jim

I agree with w8we, pick any of the ball bearing engines you listed, all will be very close in performance. The plain bushing engine (LA) has milder porting, smaller carb, air bleed low end, and is designed to be more user friendly, but has less performance. My preference would be for the TT which has great performance, quality, and price. Second choice would be for one of the OS, but costs more. Pick whatever tickles your fancy, they will all perform well.

Pilgrim

Nice question,
Difficult answer, but I am afraid you left it open. First, I think all the OS guys might be a bit dissapointed but the Rossi 46 will easily out pull the OS engines size for size anytime. But even better why worry about those little ole 46's, now there is a 52-53 (8.5cc) in many lines. Same case, same mounting dimensions. And for reference the Rossi factory spec says 2.1HP at that same 16,000 (which it easily turns on a 10x6 prop) and 2.3 hp for the 53.

So if you really want the HP open up your scope of engines, those Italians are not left behind very often!

oh, by the way, the Rossi spec sheet also lists the .40 at 2.3/21,000 which I have seen on a 9x6 rev up prop and 15% nitro.

So if you want the grunt, look for more displacement, if you want the speed, then check out the 6.5cc

Jimnie

Just get a Magnum 52 XLS for $99 and be done with it! Seriously, with the 50+ size engines weighing the same, there is not much reason to limit yourself to a .46.

Ernie

Of the one's listed the Fox .46 is probably the most powerfull, but it may not be the best choice for a novice. Also noisy with the stock muffler. The rest is about the same with very little differances except the LA and 52 sizes.

Best bang for buck:
magnum (46 or52 XLS)
Irvine (46 or 53)
mecoa
then the rest... and finally the more expensive
rossi, enya, jett[8D]

The most powerful .46 size engine is going to be a .52 or .53. As has been said, most bang for the buck is a Magnum .52XLS. Some people may like the Irvine more, but at $139 vs $99 it is a good bit more costly.

The problem with Rossi engines has always been weight. If weight doesn't matter, they are good, powerful engines, but for a fun fly type plane where weight counts, they may not be a good choice.

Practically speaking, there is probably the same difference in individual engines of the same brand as there is for different brands. I own several different types and they are all close. You will not be disappointed in an OS, Thunder Tiger or Magnum. All are top-of-the-line engines with good warranties. I also own, or have owned, Tower, MVVS, GMS, Rossi, Fox & K&B. They have all run well for me.

With the web exposing any and all flaws, I would venture to say that all .46-size engines, the most popular size, are pretty much equal. Since I have many years running model engines, since 1950, I find I can try them all and not have any problems. My new OS .46AX is a sweetheart, easy to run and powerful. If you have read my posts on the web before, you'll know I do not push OS, but the new AX is a little gem. It's not the most powerful, but it runs great in all rpm ranges. My Magnum .52XLS, and I have 2, is a few more hunderd rpm faster, but is a little trickier in the mid-range. The GMS is a little slower, but runs well. My TT .46Pro is powerful and has run well for years. I'd buy a couple more if I didn't just want to experiment around. The Tower I have I got when they first came out. It still runs well, but is showing its age. I have it on a float plane.

All of these engines will go 700-800 rom faster with a Tower muffler. I tried one on the AX, then on the Mag and ended up ordering 6 of them. $15 bucks for 800 rpm-I guess so.

If money is no cost and you truly are looking for the most speed out of an engine then this is one of the few true choices:

http://www.jettengineering.com/

Try the K&B screaming .48...in every direct comparison test I've seen it outpowers all the commonly found .46-.50 engines including the Rossi. The Webra .50GT is lighter and has similar performance with smaller props. I have two of each.

As a brand new RC flyer, your post on .46 engines ( Ed Moore ) raises a question. How do Different Propellers affect the Power and perfomance of a .46 Engine. My Club just had a 100 lap pylon race on Saturday, and some of the flyers were experimenting with differnt sized props.

I have two of the Fox .46s they are as user friendly as an engine can be, the performance king in the ones mentioned would go to the Irvine .53, also very user friendly but now MFG by OS and no longer have the very good Irvine Jetstream carbs.

Somebody has been using the search function. Good for you. That saves a lot of repetative threads on the same subject.

I've been flying 9yrs this season. Not long by some standards, but I've seen more than my share of engines.

I've just recently purchased a Magnum XLS .46 and couldn't be happier with it. It's almost a direct clone of the OS 46FX. Ran great right outta the box. I ran a couple tanks through it on the ground using my own special break-in procedure. Then I went and ran the snot out of it on a pylon racer with a 10-8 pro and 5% Omega fuel. Runs like a champ. Still breaking in, but pulling like a freight train and as smooth as any OS on the transition and ease of carb adjustments.

$59 You betcha. I'd buy another in a heartbeat.

Dave, Chris,


With his first post in RCU (Welcome!) IronHands just 'revived' a three year old thread.

I could have told Jim (w8ye) that the OS is NOT the most powerful of the engines listed, being out-revved by the ST GS-45 on virtually any prop, but I didn't...

It would beat the Magnum .46 too.

MVVS 49 is really powerful on just 0-5% fuel. Embarassing OS 46 FX on 15% in the same aeroplane

Try finding an MVVS engine in the US. I have an old .40 that I bought when Morris was importing them. It's about the same for Rossi. I had a Rossi .40 & .45, but they were more trouble than they were worth. The ones I had 15 years ago were worse than some Chinese engine for holding a low end needle setting. It used to be common in pattern circles for the guys who flew Rossi .61s to see the low end needles covered with epoxy to keep the setting. I did see one site that sold Rossis, but their price was out of sight. Those two engines may be great in Europe, but they a re really non-players in the US until they find a good distributor who'll stock parts and keep them in stock for a reasonable price.

If you are talking about 46 size sport engines then there is not all that much difference in power from one to the next. I agree with Ed that the OS 46AX is a great all-around engine. I run a pair of these with Ultrathrust mufflers on my Twin-Air.

Rossi's and Jett's are a different class of engine. I never owned a Rossi but I put a pair of Jett 50's and tuned pipes on my Duellist that I just maidened today. Ground peak with 9.5x7 props is right at 18,000 RPM and they are still breaking in. These engines are designed to run smaller props at extremely high speeds and make a lot more HP than the sport class engines.

Walt

Dar, what does your GS-45 pull an APC 11x6 (not an MA or any other brand but an unmodified APC 11x6) at with its stock exhaust on 5 or 10% nitro?

An old thread I know but....

I can't say I'm familiar with all of these engines but I have a few of them.

The OS LA engines are incredibly reliable engines with solid performance but are far from the upper end of the power scale. If you want max power this isn't the engine.

I've had both the 46AX and GMS47 and can say they are both similar in performance. The GMS seems to be more peaky than the AX and both have problems running at low throttle settings for extended periods (not a cruising engine). The GMS is probably less happier engine at very low throttle settings. Oh, my GMS47 doesn't like sidemounting either.

There are some things I don't like about the 46AX. Those damn muffler bolts break at the head or drop the nut off the end. The higher revs you run (depending on prop size) the more likely the muffler is to fall off. In the last two weeks I've lost one muffler half and just managed to retain another (3 times). Another issue is they tend to eat bearings if given a hard (but not excessively so) time. I know of 2 46AXs which have chewed up pistons thanks to bearings progressively failing in flight, mine was one of them. Replacement pistons/liners are prohibitively expensive, just buy a new engine.

Another engine to consider is the 55AX. It is very similar to the 46AX but has much more torque. Thus you can prop it to wail (12x6) or go practical (12x8). With the larger prop you'll have similar top speed and can use that torque down to pull the plane around cleanly at low speeds the 46AX struggles with.

My Strega has run both a 46AX and 55AX, both make the plane scream. The 46AX isn't capable of holding vertical indefinitely (with any prop) but it still scoots along. The 55AX can get my plane it into flutter during a dive (if I don't watch it). The 55AX with 12x6 MAS has unlimited vertical, the 12x8 MAS will hold a short hover and then fall out. Obviously, what plane you fit the engine to will make a difference but that should give you an idea.

Don't overlook the TT46 Pro. With a Tower or GMS 47 muffler fitted, these engines will eat an OS 46 FX/AX for breakfast.

Most of our club members have ditched their OS and GMS engines now in favour of the TTs and are really enjoying the extra power and spare change in their pockets.

They also last a *long* time, much longer than the OS engines.

Ed,


Why bother looking for an MVVS in the US, when you can get them anywhere else (PĂ© Reivers, Dave Moen, myself - DarZeelon) for significantly less than Morris Hobbies used to sell them?

What goes for the Rossis, with fuel management (rich mid-range, Etc.) does not apply to MVVS engines with the new MVVS carburettors (not older than 3 years).

Grant,


That GS-45 ABC was not mine, but a friend's.
I may buy one still.

The prop used was a Master Airscrew black series II 11x6. I did not have an APC and I used my 15/18/2 (nitro/techniplate/BeNOL) four-stroke fuel, since this is what I had on hand. The muffler was the stock, quiet ST type.

This prop was spun at 14,100 RPM, adjusted for flight, which is significantly more than an OS.46AX can.

Dar, when you get a chance, put an APC 11x6 on that engine. I don't trust the MA 11x6 as a reliable load. I saw one GMS .47 that did 12k peak on an APC 11x6 then do 13,800 on an MA 11x6 5 minutes later.

These are the numbers I have seen for various engines on the APC 11x6:

AX .46 - 12,300 rpm
TT .46 Pro - 12,000 rpm
TT .46 Pro (Tower muffler) - 12,200 rpm
GMS .47 (two piece muffler) - 11,800 rpm
GMS .47 (three piece muffler) - 12,000 rpm

FX .46 - 11,300 rpm
FX .46 (Tower muffler) - 11,600 rpm
ASP .46 - 11,500 rpm
ASP .46 (Tower muffler) 11,800 rpm


For the .50 sizes:
OS .50 SX and ASP .52 - about 13,200 rpm
ST G51 - 11,800 rpm

I have never seen an ST (including the .51) outspin an AX .46 prop for prop.

>> ST G51 - 11,800 rpm
I have never seen an ST (including the .51) outspin an AX .46 prop for prop. >>>

I wonder if this particular ST G51 was slightly down on power compared to most....?

Thanks,

Ernie

another vote for the $59 magnum-there hard to beat for the $$

I've flown the heck out of my Magnum 46 also and it just keeps screaming. Great little engine, just one of those that "wants to run" under all circumstances it seems like. They were on sale for $49 when I bought this one. I run the extra volume muffler off of a Magnum 52 on mine and it really likes that.

Ernie