Safe to inject pre-blower on roots type (Eaton MP-62)?
 

Is it okay to install a water jet before the supercharger? Seems quite a few people do this, stating it keeps the supercharger from heat soaking, and helps the lobes of the blower seal better, providing more boost. The manufacturer (Magnussen and Eaton) don't seem to recommend it. Anybody here have experience with this? Is it safe for the supercharger?

Two things may cause some problem,

1) Frozen water onto lobe surfaces (overcome by addingf alsohol).
2) Rotor bearing may loose lubrication (overcome by using sealed type)