Stock eaton whine stops?

[Jorday]

I now have the following mods...

JLT CAI
Magnaflow catback

otherwise stock...

I notice at WOT that the supercharger whine is very noticeable even with the stock pulley now that I have the JLT installed...The whine gets increasingly louder and higher pitched as RPM increases, BUT then at around 5000-5500ish the noise suddenly gets much quieter and stays that way until a shift is made. There does not seem to be a loss of boost or power with this decrease in blower whine. It does it in all gears it seems.

I have searched and found several threads both here and modularfords and the consensus seems to be that it's normal for basically stock cars like mine.

The question that remains unanswered after searching is WHY does this happen? anybody know? help me out here...

 

[MY DREAM]

Sounds like you need to do the boost bypass, unless you already did, in that case I don't know.

James

 

[optx002]

when i was at the dyno day at RET last weekend, a few cars stock had that drop off after 5000 rpm like you are talking about. i believe greg said he noticed it on the 4v motors and not the 2v. he didnt go into more detail. not sure exactly what it could be.

i only have an intake and catback and didnt have that drop or loss in power or whine at all. straight up hp graph and flat tq curve. good luck

 

[Jorday]

I've searched for the boost bypass mod and found may threads but no instructions that worked. The website that everyone always said has the instructions does not seem to have them anymore, and none of the install pics on any of the old threads work.

 

[MY DREAM]

http://www.rpmoutlet.com/boost bypassc.htm

Thier you go.

James

 

[HISSMAN]

Bypass, and perhaps your exhaust note is drowning it out a bit...but most likely the bypass.

-Jeff

 

[supercobra506]

if you had an aftermarket boost gauge you might see a drop off, i dont remember it happening stock...but my car was stock for 3 days before it got an upper, intake, inlet pipe, throttle body and plenum, tune, xpipe and catback. then i started to drop boost high end and now more so with an unported blower at 19psi at 6000 above sealevel

 

[Jorday]

http://www.rpmoutlet.com/boost bypassc.htm

Thier you go.

James

Thanks :beer:

I swear I checked all over that site, but I couldn't find it. Maybe I suck at the internet. :idea:

 

[Jorday]

I did this mod last night, but I didn't notice any difference when I drove the car.

 

[tv's 03]

I did this mod at the track. After, I did gain 1 mph, but this was on a car with a pulley, cai, tune and o/r H

 

[Jorday]

I still want to find out why the noise gets quiet all of a sudden. Anyone else have any ideas? Somebody has to know.

 

[BLK04]

My car also does this. Im going to try changing the belt and see if that helps.

 

[Jorday]

Let me know if a new belt makes any difference.

 

[Zona-Terminator]

That sounds like belt slip to me ???
Get a BF tensioner, then listen to it. You should get one anyway.