Gears & Axles - Cam and gear question

Ok I ran about 5 runs a couple of weeks ago in the 12.2 and lower range.All the 60's were in the low 1.8 range and 1 1.749.Now when I let off the gas I hear and overwhelming whine. The sound only occurs when I back off the throttle and remains untill I get on it again.When I am on the gas it sounds normal.I am installing a cover for the rear this week.
If I blow the rear I would like toput 373's in and a TR224 cam.Do you guys think I will get the same performance or alittle more.I will be getting more HP but taking away gear.My ultimate goal is to set the car up for a blower.What do you guys think it will do with less gear and a bigger cam?Any help would be appreciated.

My mods...
2001 Camaro SS M6 t-tops,all SLP options,Pro 5.0 w/Lou's Short Stick,lid and filter,Mac headers w/ORY,HPP3 and 4.10s.

You might ask in FI, but with a blower set-up, you may be better going back to 3.42s or even 3.55 (depending upon the rear you choose), based upon the how much boost you run. 3.73s will be fine for a typical stage 1 boost situation.