I have a two ignition systems, one is for the Evolution 58, the other is for a MVVS 26.

The Evolution label: ICU-l S/N13298 D:11/08 240M20

The MVVS label: ICU-L S/N 12139 D:05/08 240M20

How do you tell which engine it is for?

You can change the timing on the MVVS 26, you can't on the Evolution 58. Horizon told me that was correct, you can't change the timing.

I might have an ignition problem(spits and sputters) on the Evolution and I wanted to swap it with MVVS ignition because it is not in a plane.

Thanks,

George G. Royal

You may never know until you try.

It will not run right if its not correct

Try.
Both are ICU-L types, though it seems that MSR makes slightly different ignitions for the Evolution line.
You should still have warranty on the 58 ignition, if not older than one year.