Okay I guess I got my acronyms messed up. I am talking about an R/C mixture control, so that's an MCV. Can those serve as the primary mixture control, i.e. as the needle, is that what they are meant to do? Or is the regular needle still fitted and these just vary conditions ahead?

MJD

EDIT: looking at the Perry site, it seems it has a manual adjustment for the mixture range, or midpoint if you will, so yeah I guess it can do all the RNV/MCV work.