Anyone have trouble with an excessively noisy SC setup? Im not talking about the boost whine or centrifugal whistle. This is what Ive got at idle venting to the atmo. A full intake didnt help at all



Would adding some form of silencer or reshaping the inlet material help?

 

I don't know if you've had it plumbed into the TB yet but seems from the vid that it may get quieter if it's sealed up to the TB. Either that or you ended up with a noisy unit.

 

Intake didnt help at all, nor did swapping the blower for my backup unit. I looked over about 20 swaps with this blower and some were noisy, others not so. The quieter ones seemed to use a smoother inlet transition from the 4" tube to 1.5" long oval. Ill give it a go and see how things work out

 

sounds like it doesn't have fluid aren't those meant to sit flat maybe all the oil is be tilted away from the bearings?

 

Did you mess with the sound deadening slots in the outlet? Did you mess with the inlet shape?

Unfortunately, that is what they sound like, incredibly, you can pull the belt and let it freewheel and you'll get most of the noise by just sucking air through them, most of that noise is airflow through he rotors. In OEM applications they kill some of that by specific inlet and outlet casting shapes, manifold layouts and by putting the throttle body in front of the inlet, blocking much of that noise part throttle with the throttle blades.

My brother's car has his intake plumbed through the firewall, using the HVAC ducting area to house a filter box and before messing with assorted sound deadening it was LOUD... we borrowed a dB meter and got 121-121dB at head level in the passenger seat at WOT

 

According to Eaton, they can be clocked to any angle. The oil is self contained in the snout

I didnt touch the silencer holes at all. Actually the blower is exactly how it came off the T-bird plus the snout rebuild

I did reshape the intake for the inlet hoping to cut down on the air turbulence. Battery was dead so we'll see if my work was worthwhile tomorrow

 

The outlet isn't hooked up to anything yet? When you say that a "full intake" didn't help did you mean that hooking up the outlet side of the blower to the intake on the engine didn't make any difference in the noise?

A roots-style blower working with an open inlet and outlet is moving a LOT of air. Certainly that is going to make some serious noise.

The blower on my Malibu is about dead silent until the throttles get whacked open and then it screams. Of course, mine isn't moving much air at part throttle because it's below the throttle plates (carb setup). You can rev it, but it's pretty much silent until you put it under real load and open the throttles far enough that the air is dense enough for it to really grab onto. Yours is running like that at all times, however, since it's before the throttle plate.

Does that blower have a bypass valve? If so, is it working?

 

Yes, the full intake was installed and the sound didnt diminish. BOV was tested and installed. At idle it was maxed out and still building an excessive about of boost, but thats another thread

 

WoW!! That's crazy loud.....it would drive me nuts! If I heard that on a car and didn't know it had a blower, I'd probably ask the owner if he had an alternator going bad...

Hope you figure it out...

 

On a roots you have to have a throttle body before the blower inlet. Otherwise you are making the blower work 100% all the time, plus its trying to cram air into the engine but it's being blocked by the throttle body when closed. BOV's and roots together are like a brother marrying a sister. It just ain't right

Put the throttle body ahead of the blower and get rid of the BOV and all will be well.

 

The gentle transition of the new intake greatly reduced the noise, but it's not gone. Hopefully it wont be quite as annoying over time. Atleast it's not bad PS pump loud anymore

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Redoing it


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