Well, I installed my pulley the other day & all seems well, but I have a new sound.
Of course there is the increased intake whine and it happens at lower RPM, as expected. However, I have a new turbine kind of sound coming from the belt area. It's higher-pitched than the intake sound & is present from idle on up.
I've looked at the belt (Gatorback) & it seems fine. The sound is not really objectionable but is a little piercing at higher engine speeds, especially next to a wall or guard rail.
I don't think it's a failing bearing, but I could be wrong. For what it's worth, my SC was replaced at 4k, & the tensioner at about 15k. I have about 19k now. Anyone else experience this kind of change after the pulley?

 

Why was your blower replaced?

back on topic; which pulley are you using, and did you use the same Gatorback belt prior to the 19%? This would rule out inherent noise the Gatorback makes. Where is the plunger/indicator for the belt tensioner reading?

 

I'm quite sure you are hearing the SC whine due to it's increased speed in relation to the engine. Before the reduction, the engine noise would drown out the sc whine.

 

I had a screech/squeal from the belt area. Dealer said it was the SC & did it under warranty. The screech returned in about 1k miles & this time they replaced the tensioner. Screech gone. That's when the "tick" started - see other long & winding thread (nutshell - tensioner replaced again, then damper, problem mostly solved).

Initially, I used the NAPA 060539 (came with pulley). Ran about 20 miles & found NO holes showing on tensioner. Got the Gatorback 4060537 & now have most of a hole showing - has remained that way for the week following install. Noticed the sound after installing the GB. Is this sound common for this belt? I considered swapping back to see if the noise goes, but haven't yet. How many holes should be showing?

 

I also complained about this type of noise after 15% and Alta cai, and was told it was noise created by throttle body at small openings.Doesn't always happen,but when it does,it is ear piercing,I likened it to the noise a mic makes with too much gain(feedback).When you mentioned worse going along walls or guard rails, that really struck a chord with me.Talked with morefun at the dyno event in providence and he complained about it too.He replaced the foam alta filter with K&N cone type and said it got a lot better, FWIW.

 

I swapped my BMP for the stock airbox, but that didn't change a thing - it's definitely coming from the belt area and goes up & down in pitch with the engine RPM. I think it's just the Gatorback..

 

Gee it sounds like the tensioner again. Could it be?

 

I don't think so. It sounds different than that. Anyone else running a Gatorback? Does it naturally sound different than other belts, and how many holes should show on the tensioner?

 

you should have about a 1/4" of the plunger on the tensioner sticking out, if that makes any sense whatsoever

 

Here's a pic to illustrate Ryephile's point:

 

Just did the Wicks Driving Academy in the car & all is good - belt has not stretched, sounds the same. I'm gonna assume that the gatorback just sounds that way.

 

Well, I got tired of the turbine & put the flimsy 539 back on. The noise was the gatorback. It was driving me nuts. Not noticeable with the windows up, but awful with them open. Anyone else have belt recommendations?

 

not the NAPA 535 - too strechy. no holes left after only 6,000 miles.

and i dont tach high on a regular basis or drag.

ive heard the 539 is good if you don't like the gatorback

 

The 539 already has no holes left at 20 miles (!), & the stitching already looks frayed on one side. Yes, it is installed correctly. The NAPA belts seem thin & spindley compared to the factory Conti or the beefy Gatorback. Anyone tried other brands?

 

FWIW, I have 15K miles on my 539 Napa w/15% pulley, it's still good. Thin and spindly is the point, as it wraps around the small supercharger pulley w/out slipping, unlike the anti-bend stock Continential belt.

I'm not sure what belt to run for a 19% pulley, but the 539 seems like it would be too long, and the 535 is apparently inherently evil.

 

I just switched to the Gatorback belt and now have the SuperWhine that you describe. I glad to have found this thread to confirm the noise I also beleive is from the Gatorback belt.

It kind of has that dual supercharged sound! Or might be better decribed as the supercharged desiel semi-truck you hear on the highway.

The whine is more prominent at mid RPM's and just off the throttle.

 

Yup, that is totally normal for a Gatorback belt. I've used them for years on my other supercharged cars - I like the added whine