Over the last few days I have been experiencing a ver strange noise coming from somewhere in the vacinity of the S/C, unfortunately it is intermitant and when I took the car down do the installer there was no noise...

It is RPM related and almost sounds like a belt rubbing ....

any ideas or experience with this problem??

Colin

 

Things are getting worse .... now I have a high pitched ringing tone as the rpms drop off (3k -> 1.5k ish), kinda like a tuning fork ringing sound.

The more that I think about it the more I am thinking that it is the tensioner bearings ...

No one have any ideas??

Colin

 

I herd about a guy through Boulder Nissan that had a bearing go bad on his Stillen kit, the kit wasn't even that old! I remember if they said it made any sounds (I'm sure it did) but one of the pullyes had a wobble .
Do any of yours wobble that you can see?

 

Not really, I was checking it last night and it is really hard to exactly pinpoint the location of the noise ...

Colin

 

When you get it to make noise try using a long screw driver and move it from part to part with the handle agains yuor ear where ever the noise is the most pronounced is your problem area

 

That or use a stethoscope.. thats how I found out the problem with my previous s/c.

 

Thanks for the suggestions, I'll give them both a try ...

given that power is still really strong, I'm just gonna run it till something breaks ...

Colin

 

subscribing...

 

Yes, it's time to resurect this ol' thread ....

So, it all turns out that air was being sucked in through the thread of one of the two hoses that connect to the back of the intake thingy, AFTER the MAF but before the S/C and so not only was the engine playing a whistling noise constantly, but I am assuming that I was running lean due to un-metered air being sucked into the engine .....

Anyways, all is fixed, not just need to throw that 8lb pulley on

Colin

 

Glad to hear you got it fixed. Those little issues can drive you nuts! Lets see some numbers now.

 

More to the point, let's get Joe out for a good spanking

I'm gonna phone Mr.Dyno tomorrow and see when he can fit me in ....

Colin

 

let me know how that goes, i am very interested in that pulley.

 

Will indeed, I'm booked on the 13th sept, damn are they busy ..... apparently TTing a Z and a G ... one greddy and one APS .... hands up if that's you ...

Still have a slight whistle though, only really audiable when 0 throttle at low revs ... probably still a little air leaking past the thread .... I'll figure this all out by then ......

Colin

 

Okey dokey .... an update ... I still have a vacuum leak which is proving REALLY hard to track down ...

I put the gold pulley on which is currently giving me 7.5lbs of boost. I dyno'd at 327rwhp 294lb/tq so I'm pretty happy, although I think that I am losing some boost because of this leak.

the sheet ...