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Discussion Starter · #1 ·
If you've been playing along at home, you know I put a Borla exhaust on my car (bought from Amazon) last week.

It's a blast to drive with, but there seems to be a subtle 'honk honk' when I dig hard into the throttle. It's sort of a cross between a kid's bicycle horn and the note of a typical monotone car horn. The volume is well down below the engine and exhaust noise, but if you listen for it, you'll hear it 2-3 times each time I am under max torque. First time or two I heard it on the street, I thought I must have jumped in front of somebody and they tooted at me.....

Anybody heard this? Or fixed it?

As I type this, I'm thinking about those guys that play water goblets by running a moist finger tip around the rim to get them to 'sing'. I wonder if under torque my rear propshaft is just touching my exhaust pipe and making it 'sing.'

BTW, the Borla got mad props at an Audi track weekend. The Audi club here attracts a mixed bag of serious car nuts all the way down to first timers and teen 'defensive driver' class attenders. A lot of folks had never heard of an R32, but they've 'heard' of one now....
 

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Try to get a video or sound clip for us.
Yeah, you should try to get a sound clip. I have a weird sound in my Borla's too. Sometimes it's there, sometimes it isn't. It's at a very specific RPM too.

I also agree that the Borlas get some really great compliments at track days!
 

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Maybe the exhaust is slipping a little and the metal on metal is rubbing. Kinda like when you do the finger on the rim of glass to make the glass hum...
 

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Discussion Starter · #9 ·
I would really like to hear your borla setup, iv got the Tampa mod done to mine and like it but would like to hear yours in person. Lmk if your ever in the Olympia area :thumbup:
I was seriously considering the Tampa mod and the flapper 'switch' that somebody is selling here, but I stumbled into a great deal at amazon.

$545 with free shipping, with Amazon as the seller. When those two sold out, they're now listed as $822 + 10 shipping from a third party, with Amazon listing 'out of stock' but priced at $719.

I was going to suggest you and I connect on a PNW R cruise, and I see you're on that thread already.....

John -
Good times with the Audi club. I'll be back. I'm starting to work on Mrs_Peach about maybe doing the next DE either double driving my R, or she can bring her MCS.
 

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Discussion Starter · #10 ·
Try to get a video or sound clip for us.
Seems to be beyond my skill set.

I've done a half dozen video clips with my iPhone4 clamped to the window. I can hear the 'sing' live, but it doesn't show up on the video. Too subtle for the overloaded mic to record. I have been having fun listening to it on headphones though.......

It's now more of a 'sing' than a 'honk'. I'm thinking it's the propshaft just lightly grazing the exhaust under some circumstances. Probably the 'honk' was the same thing, it's just the speed with which the exhaust bounces or grazes the propshaft.

I'll look at it again on the weekend. If I can't see the interference point (probably shiny now) then maybe I'll get the car 'race naked' again and see if I can get a cleaner sound clip without the dead hooker in my trunk.
 

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This sounds exactly like an issue brought up on this board a couple months ago. someone had the prop shaft rubbing on the exhaust at certain points.

Turned out, IIRC, that when enough water splashed up on the exhaust pipe it deforms slightly and taps the prop shaft. A simple bracket adjustment fixed it if I remember right.

You can clearly see the rub marks on the prop shaft if you lift it and take a look.
 

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Discussion Starter · #13 ·
This sounds exactly like an issue brought up on this board a couple months ago. someone had the prop shaft rubbing on the exhaust at certain points.

Turned out, IIRC, that when enough water splashed up on the exhaust pipe it deforms slightly and taps the prop shaft. A simple bracket adjustment fixed it if I remember right.

You can clearly see the rub marks on the prop shaft if you lift it and take a look.
Thanks Jason, that might have something to do with it. The 'honking' I heard was acute on a wet track day.
 

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Discussion Starter · #15 ·
Well, I think I got it sorted.

I took a few photos, and then proceeded to bump the Borla mid-pipe forward a tad.

The photos did not show me what I thought they did until I reviewed them on a big monitor (not the dinky chimp thing on the back of my P&S.

Here's one I thought was useless:


.... but then when I reviewed it, I saw the shiny bevel on the propshaft.

Here's the other one:


Under the car, I got fixated on the bright 'weld', and thought that was a rub point (scratching my head on how a rub point could get 'so deep').

On the big monitor, I can zoom in on the semi-circle arc on the top edge and go "A-ha! This is why the fat lady sings!"

Hopefully my adjustment takes care of it.

Link to Hi-res files for those interested:
http://www.thepeaches.com/R32/Borla/

side note: small digital cameras are "the tits" for this sort of stuff. I've always been a shooter, had a brutally short career as a PJ when I was a kid. Used to be the Polaroid SX-70 was the great "troubleshooter's friend". Now it's the digital P&S.
 
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