Just look in the 1% P-36c. If you have Excell, open the spreadsheet, and whala, in WEP you have 3 choices, Water, Methanol, and Supercharger.

Using WEP, the P-36 supercharger puts out the power from about 900 o 1200 hp, and although it does turn off after 2 minutes or so, you can turn it back on and it seems to stay on!

This means (possibly) that if you want to use a blower as a special key toggle, you can use the F4U-1, F6F-3, F4F-4,P-36, P-35, P-40,  and probably other early foreign aircraft to model a blower for going above 12,000 ft. or so...
This info would have to be modeled in the spreadsheet. Not sure if you can have both a supercharger, and say water injection.