I'm currently looking at Magnum/ASP 46/52 engines. I'm curious where they fall in line as far as output. I assume between the LA46 and ST60. Also, is anyone running them with no mods other than a  venturi and NVA? How about approx. size airframe (600 sqin.)?
TIA
Steve

More equivalent to a ST G.51...which is a ST .60bb in output but at a bit higher rpm with flatter pitch props...a good thing. The nice thing is that they should be happy (once run-in) on good quality R/C fuel, such as Wildcat Premium or Powermaster 5% x 18% or 10% x 18%, since they are ABC and not ringed. I'd likely add 2 oz of Randy's Aero-1 per gallon. I'd at least try the 12.25 x 3.75, 12-4 and 13-4 APC's or whatever else you can find in that range. Look at XOAR wood props to see if they make a 12-4 and 13-4. There should be some CF props that would work, if you're interested?

Last I flew a G.51 (a T&L CL version), I used the 12.25 x 3.75 per Dan McEntee's recommendation, and it was pretty happy. I'd expect much the same from the stock ASP/Magnum, but the only one I've (bench) run is an SSW rework with the blocked boost port, and a GMA rework that had some loose tank issues.

Blocking the boost port is not a major deal to do yourself, if you wish, and it's also easily returned to stock. Leonard uses a pretty large venturi to recover some of the "power" lost, so the fuel economy isn't so good. Locally, Pat Johnston, Randy Powell and Mark Scarborough have all flown SSW reworked Magnum/ASP XL .53's in various airplanes typically powered by ST .60bb's. Pat says it's an exact replacement...same power, same props, same run, but lighter. The XLS engines would not be so much lighter. Look to Randy Smith for a lighter tube muffler. He can also provide a venturi and NV Assy.  I'd expect a .272" or .281" would work pretty well.

The current XLS engines are a bit heavier than the old XL series, but they're what you can get...and get parts for. I have an XLS .46 and an XLS .52, if you need bare weights, I can put them on the scale for you. Typically, the bigger displacement version is lighter, because they're built on the same crankcase casting. More emptiness inside with the bigger bore. I'd suggest 650 to 725 square inches. Maybe bigger than you want. Think Impact or Trivial Pursuit size. Not many suitable profiles, but maybe a stretched Pathfinder or Cardinal would work.   

I mourn the passing of the Magnum XLS .36...sweet little engine, excellent on a Twister, or most any .35 sized Classic. For awhile after it was discontinued, you could still get the ASP version, but now it's gone also.    Steve

My buddy says all the asp's bigger than .40 use the same case as the 60, so they will be quite heavy.
R,
Chris

     Hi All:

     I have no idea as to how much smaller ASP engines weigh, but I have an ASP .61 that weighs 19 oz.  Is that heavy for a .61 nowadays?  It is an RC model, first flip starter and is very powerful. I can not imagine using this engine in UC.  A friend of mine threw I away and I got it out of his trash bin. I am sure that it was never run.

                                                                                                                All of the best,

                                                                                                                Frank McCune

Just saw a NIB TT pro46 for sale locally, $85. How do these compare to the  magnum engines? Would it be comparable to a ST46?
TIA
Steve

That's a real good price for NIB. Randy Smith can provide the CL conversion bits and a much lighter muffler...and/or do his rework. It'll be a lot bigger, heavier and much more powerful than a ST G.21 .46, but should burn less fuel and require less nitro. I'd buy it and call Randy, or call Randy and then buy it.

There's no relationship between the TT .46 Pro (from Taiwan) and the Magnum/ASP engines (from PRC), tho the same unemployed OS designer may have designed them both...and others. Weird how that works? Randy may well know about that. The TT's are better made, but have ABN (which is actually ok), while the Magnum/ASP engines are not quite to the same level, but have real ABC. As for stunt run stock...we've had a couple of Expert fliers try to run a stock TT .36 Pro in Classic with less than stellar results...runnaway problems. The Magnum XLS .36 is easier to get working in stock form. Whether this transfers to the .46 > .52 is an unknown locally, but again, Randy probably can tell you.  Steve

Theres a bloke here running a FS 46 OS in a Yellow Plane . Doesnt seem to have any trouble . If its 4-2ing , its doing it soft .



Stunning Resemblance ! to the T Tiger ,. Wondering if the FS is a recased FSR . If I find a el cheapo swap meet one , We will know .



Though T Tigers more FX OS ish , which is a recased FS ?   

Had Randy do his thing, haven't even bench ran it yet. really need a bigger plane  than I'm currently flying. I'm rebuilding a Tutor II arf, but it has a LA46 waiting. Still trying to work thru the pattern, don't really want to tear up a good plane/engine combo. Hopefully I'll be where I can build something for it this winter.
Steve

My flying buddy said the same thing....
He says it should make a noticeably more amount of power than an LA.46.
I believe him,  he's been spot on so far.

R,
Chris