flybyjohn

My Feedback: (2)

Does anyone know the difference between these two engines. I know they run different rpms but what is different about them, bore? stroke? timing? carb?. I cannot seem to find the specs on the 25 xls anywhere and the specs on the instructions for the 25xl say the stroke is only 8.5mm which I know is wrong. Can anyone shed light on this. Can a 25xl be converted to a 25xls by changing the carb or something?
Thanks

Montague

They are totally different engines, I haven't actually checked the parts numbers to see what might be common between them, but I do have both engines. They look nothing alike, and I'd be surprised if any of the major parts fit between them. OTOH, it almost looks like a Mag .25XLS might be able to swap some parts with the OS FX. Probably not (and haven't tried), but it sure looks like it.

Anyway, you won't convert the XL to an XLS. It's more than the carb or the case or the piston/liner.

vertical grimmace

My Feedback: (1)

What kind of performance with this .25 XLS? Which prop, what RPM and with without can? The .25 FX was getting mid 19,000 with a can and a MAS 9-4 prop. That seemed to be the sweet combo on the Open B planes.

Montague

We don't fly B class or with cans around here, just some 2548. In the air, my hottest .25FX's (some of which did more than 19k on can back when I did fly B class) are putting out about the same as the other guys with their new XLSes, you can't tell the difference in the engines in the air in 2548. Others here and elsewhere have said basically the same in B class as well.

I do wish Magnum would go away from the press-collet type of prop hub and use a keyed hub like the OS FX. It's such a hassle to get string out of the bearing on a Mag .15 at the field.

draftman1

the XLS here in so cal is hitting the low 19000's without a can and a mas 9-4. the guys here are not using cans on them at all in open B

Crosscheck

Hi All,

The 5or6 Mag.XLS.25s are running great here. Equal performance to the OSFX.

MA 9-4, 15%, baffle out of the stock muffler... we are taching around 17K on the ground. (a bit rich on a full tank)

About $25 cheaper here than an FX, and it comes with allen cap screws (and wrenches !
Very nice engine, we cannot find any flaws...

flybyjohn,
Never seen a MagXL so I cannot comment on parts interchanability with the XLS.
We figure the XLS is a clone of the FX internals, because the performance is so close...


The OSFX.25s are great engines. Some of ours have many many gallons through them,
And they still perform great !

Take care,
Have fun,
Dave'crosscheck'Fallowfield
Maac 6437
Unabashed Combat Team

Crosscheck

Hi All,

Out of curiosity, I found my instructions for my OSFX.25s and MagXLS.25s...

-they both say a bore/stroke of 18mm/16mm.

-I weighed both engines, ready to run with a MA 9-4 and DuBro spinner nut. Stock mufflers with baffles out.
(12.20 oz. for the OSFX.25, 12.25 oz. for the MagnumXLS.25.)

-mufflers are interchangable. They both fit the same holes in an engine mount...[8D]

-the XLS has a 'squarer' head, and less#, but bigger cooling fins than the OSFX.

We'll keep running the snot out of them...

We recommend the XLS because they have matched the 'old price' on the FXs, before they got discontinued, then re-issued at a higher price.

Take care,
Have fun,
Dav'crosscheck'Fallowfield
Maac 6437
Unabashed Combat Team

P.S. Kirk, I just re-read your post... the MagXLS.25 has a keyed prop drive...[8D] Not a collet type...

P.P.S. The Combat Pilots I fly with all have a sense of humour. (Why we Like It !) If anyone of us complained about getting a string caught in his prop...
The answer from all of us would be: "AIM for the STREAMER ! ! !"... HeHeHe