PAK26499

My Feedback: (3)

Any thoughts, inputs, opinions etc for which one would be the best choice for the Magnum R would be greatly appreciated.

I know they recommend the 52V1 however am wondering if the .56LX would have the same speed capabilities? I would honestly rather go with the Jett.

In the meantime I am going to start flying with an OS .55AX with the Jettstream muffler, and pending everything goes well and I am used to the airplane.........I will step up the engine. I want to go fast but will plan on using off the shelf fuels. Most likely Omega or Wildcat.

Thanks in advance......

lfinney

My Feedback: (44)

stick with the jett, less wear and good parts availablility

MJD

My Feedback: (1)

I've flown a Magnum R on both a West .50V1 and a Sport Jett .50. I would say they were very close, with the edge on top end speed slightly in favour of the West, but I had it set up with an open pipe and set up for in air rpm around 21k running trimmed APC pylon props with 9.0 or 9.25 pitch. Whereas the Jett was the stock Sport Jett .50 with red Jettstream muffler and running full 8.8" pylon props at 2.5k lower rpm. I think you would be very happy with the Jett. I run 15% nitro syn/cas Wildcat or Omega fuels in my Jett and it seems quite content. Jett's instructions for the Sport Jett
tell you to use any good quality fuel with minimum 18% oil and some castor, and 15% nitro gives best results.

vicman

My Feedback: (10)

You will be happy with the Jett.
Be sure to read the other threads in here on the Magnum. The CG is a little different from the instructions and makes a huge difference in surviving launch.

combatpigg

My Feedback: (3)

Does the Jett .56 use the same size [large] shaft as the Nelson .40 [5/16" prop nut] or is it the standard .50 and under shaft with a 1/4" prop nut..?
The smaller shaft .40-.50 sized engines just wont have the air handling capability to graduate out of the 180 mph [and under] class. I think the air passage that runs through the shaft is the limiting factor.
A new Jett engine is a lot of money, so before I spent it I'd want to know what that engine's upside potential is.

airraptor

My Feedback: (66)

The Jett 56 will spin a Stock APC 9x8 at 18,500. The Jett will outlast the webra/weston. The Jett engines are the longest lasting engines I have ran except maby an Enya but havent had a new one in long time.

PIG the 56 if I remember correctly has a hole of .460 which is plenty big. I will go measure again.

evan-RCU

Why will the Jett outlast the Weston? I have one of the first Weston V1's brought into the US, 10 years old I think with a few hundred flights on it still runs great.

MJD

My Feedback: (1)

I have not seen any evidence of a West .50 powered Magnum R exceeding 165mph, regards the .52 don't know. I dropped my West .50 out of the Magnum R and onto a Demon and would guess it pulled it 15mph faster than the Magnum. But top speed was not likely any higher than 175, maybe 180 tops out of a shallow dive. And top speed of the Demon was similar between the Sport Jett .50 and the West .50, though the West might edge it out on the right prop. And again, that was on an open pipe (aka "nitro" pipe).

The Jett is such a painless engine to operate and so well mannered for the immense power it produces, hard to fault it in any way. The West is not a big deal to run either, a very nice engine. The Jett does what it does with a bolt on "tuned" muffler, versus a pipe. Much less hassle and in the end I think a far more durable and versatile engine. My West fragged the big end on the first run, on syn/cas 18% oil 10% nitro sport fuel, in a rich 2 cycle after warming up, and Weston blamed it on the fuel. Granted, they repaired it quickly and returned it to me no charge, I will say that for them. Even Jett identifies the "first run" syndrome, which is part of the reason they run every engine at the factory.

In the end, of the two I far prefer flying the Demon on the Jett .50. I would expect a similar reaction/comparison between the .56LX and the .52V1, and the fact that the LX is slightly higher timed and larger displacement than the SJ .50 would lead me to expect the Jett to pretty much close any gap that may or may not exist.

EDIT: oh yeah, if we're voting, I recognize the West is a killer engine but my vote goes to the Jett.

lfinney

My Feedback: (44)

previos posters here in the speed forum have posted that the sleeve and piston on the west engines seem to wear much more quickly, at the 18-21 k range, my concern would be long time parts availablility with the west engines with their webra origins

PAK26499

My Feedback: (3)

Sounds good. Thank you all for the input.

combatpigg

My Feedback: (3)

I bought the Webra .50 shortly after it was reviewed..IIRC late 1980s. It was rated something like the 4th or 5th best power to weight "production" engine of all time by one of the model mags back then. IIRC the Webra Bully was in front of it.
I bought a factory replacement P/L and bearings for it sometime between then and now but it's only been the past 4 years or so since I bumped the exhaust timing up to 180 and started running it above 20,000.
I think it has clocked in the 170s on a Screamin' demon with a Mac's pipe. I run it with a 10 mm venturi and crank case pressure.
IIRC I did a thread here to show the basic steps involved with giving it a power tuneup.
I ought to do the same deal with my Jett .46 to see if it can match the Webra .50...naah]

vicman

My Feedback: (10)

Whew![&:] That was almost the end of a good friendship!

freakingfast

My Feedback: (3)

From what I have gathered from websites and reported numbers is that the Jett 56 is in a league by it's self, perhaps the most powerful sport engine for it's size ever made. Jett nailed it with this one.

I had a Webra 55 (round black head) and it would blow away an OS 50 FX or a Magnum 52*. Surprisingly, an Evolution 60 NT* is stronger than the Webra 55. All comparisons with tuned exhaust.

(*) these engines when operated with tuned exhaust had poor mid range/carb issues.

bob27s

My Feedback: (19)

Id enjoy seeing another Magnum build in here... been a while

john josey

It's been nearly three years since i did my own build on here, the model is still alive and well and used on a regular basis. flight numbers must be somewhere between three to four hundred and i have to say, i thought the west 52 would have given up long ago but it's still going strong.

PAK26499

My Feedback: (3)

Gonna start the Magnum build once the Parts arrive via UPS. I forgot I have a .46 FX with jettstream muffler or a .55AX with jettstream muffler to choose from. I remember doing tach readings a while back on the FX with jettstream and really revved up (for sport engine standards that is) with the smaller 8-9 inch props. I forgot what the readings actually were though. Would you all say the FX may actually be the better choice for speed?

freakingfast

My Feedback: (3)

No, not necessarily. The 55 AX & Red Jettstream should really honk with a 10X9 APC. It should be about 14,500 rpm once it's run in for a while and that's where this engine likes it, don't try to make it a screamer. It will be faster than the FX and the flight time will be longer. Use an OS # 8 glow plug and Power Master or Wildcat 15% nitro max.

PAK26499

My Feedback: (3)

combatpigg

My Feedback: (3)

The fastest Magnum I know of hit 195 mph with a Nelson Q-40 engine with a $4 APC pylon racing prop. It will be interesting to see how close to that speed a comparably priced Jett .56 pulls your Magnum.

MJD

My Feedback: (1)

AFAIK the highest tracked speed for a West .50 powered Magnum is about 165mph. However, Weston UK was able to routinely exceed 200mph with this combo, using no more than inflated ads and box copy.

PAK26499

My Feedback: (3)

Well all the guts are in. Still have to make all the final trim adjustments etc. Major bummer is the CG with everything as far aft as I could get it is running around 90-100 mm from wing root. Looks like im gonna have to add close to 10 ounces to the floor behind elevator servo unless I can come up with something else to get the target 150 mm.

Definetly gonna junk those nylon clevises for metal ones and upgrade a few things to make it safer. Otherwise a very straightforward build. Took about 8 hours and I'm slow.

Gregor32

My Feedback: (1)

Looks really nice, just a thought those magnum spinners are very heavy, you should try a tru-turn much nicer and very light, it might help with the cog.
Regards gregor

MJD

My Feedback: (1)

That's not a great spot for tail weight, better to get it right in the arse end and take advantage of the moment arm. Small hole, BB's or lead shot in the very rear of the fuse, add epoxy and let cure.

The difference in CG for a piped engine and with a Jett Stream muffler is noticable on Magnums and light deltas. You do not want to fly a Magnum with a CG forward of the recommended range unless you enjoy belly landing at 50mph. The rearmost Weston recommended CG is still plenty forward. Many people fly with the CG farther back than Weston recommends (I've heard as high as 190mm+), but leave that for later. You'll find info here if you search Magnum threads, there was oodles of discussion circa 2-3 years ago.

I forget if this is your first Magnum - leave lots of height before you kill the engine or run out of fuel, so you can get used to the glide slope. It's nothing to sweat about, but if you try to horse it around at low speed/height to make the field, you can issues.. guess how I know.

PAK26499

My Feedback: (3)

Good ideas.  Thanks!   I found if I stack 3 receiver batteries (3.3 oz each) behind the section where the elevator servo is I get perfect balance at 150MM.  Thinking I am gonna order a square receiver battery (all I have is flat and that wont fit).  No sense in not using the receiver to help balance this thing out if it only costs $17.00 for the battery

MJD

My Feedback: (1)

Hopefully 6-7 oz in the battery tray translates to a bit less in the tail. Although that area is pretty far back already.

The West engine is not overly bulky, and the Genesis pipe puts a fair amount of weight rearward compared to a tuned muffler.

At least with that honking prop on the front you can probably hand launch it vertically. Not so with clipped pylon props on the West, but once it hooked up.. ka-pwing!