ORIGINAL: w8ye

It is likely that it is

The Evolution is a derivitive of the Magnum XLS 61 which is a copy of the OS 61 FX

These engines are all the same

<font size=''4''>O.S. .60 FP & LA, .61 SF, .61 FX,.65 LA, .75 AX
Evolution .61 NT (not the .61 NX)
Irvine .61 (NEW - bolt through)
Jett .67L -.76L (not the .60L)
Magnum .61 Pro
MDS .68-.78 FS Pro
Thunder Tiger .61 GP, .61 Pro (bolt through)
Webra .61-.75 P5-H </font>