I've been getting some noise from the supercharger for a long while now. This noise occurs at certain points on the tach (typically at ~2K and quite noticeably at ~3K). I don't hear it at all at, say, 2500. It's worse when the blower/engine is hot. It's generally at its "worst" when at part-throttle although blipping the throttle when downshifting often results in a sharp sound too. I don't hear it when the throttle is closed and the engine RPM is dropping through 3000.
The sound is hard to characterize. If I had to describe it I'd say it's a "howl" or maybe a "hum" of moderate frequency. Interestingly, the frequency stays about the same at 2K and 3K but the intensity goes up at the 3K point. I'm guessing the rotors may be contacting the case ever so slightly, causing it to resonate. The blower doesn't make any bearing-type noises and still builds good boost. As far as I can tell, the drive coupling in the snout is fine and the blower feels smooth to rotate by hand.
I bought the kit used about 3 years ago and, aside from the sound, the blower has been trouble free. I've changed the oil several times now and check it pretty much every time I take the car out (maybe weekly) and when I fill up I check the engine and blower oil. I think it might have a small leak as the manifold behind it develops a sheen of oil but the level never seems to go down.
Anyway, I'm thinking of taking the assembly off the car and having it reconditioned. The sound is plain embarrassing and I may be mistaken but I believe it's getting worse; I'd rather not risk doing irreparable damage by driving it much longer like this.
I've found three candidates for rebuilding it: The Highspeed Lab, Jon Bond and PSE.
I'd appreciate any feedback anyone has who've dealt with these or who have alternate ideas.
The sound is hard to characterize. If I had to describe it I'd say it's a "howl" or maybe a "hum" of moderate frequency. Interestingly, the frequency stays about the same at 2K and 3K but the intensity goes up at the 3K point. I'm guessing the rotors may be contacting the case ever so slightly, causing it to resonate. The blower doesn't make any bearing-type noises and still builds good boost. As far as I can tell, the drive coupling in the snout is fine and the blower feels smooth to rotate by hand.
I bought the kit used about 3 years ago and, aside from the sound, the blower has been trouble free. I've changed the oil several times now and check it pretty much every time I take the car out (maybe weekly) and when I fill up I check the engine and blower oil. I think it might have a small leak as the manifold behind it develops a sheen of oil but the level never seems to go down.
Anyway, I'm thinking of taking the assembly off the car and having it reconditioned. The sound is plain embarrassing and I may be mistaken but I believe it's getting worse; I'd rather not risk doing irreparable damage by driving it much longer like this.
I've found three candidates for rebuilding it: The Highspeed Lab, Jon Bond and PSE.
I'd appreciate any feedback anyone has who've dealt with these or who have alternate ideas.