...closed....

[inTgr8r]

I had a brief discussion with the guys at DKF regarding an anti-drone product for exhaust systems.

The concept is to take industrial engineering practice and apply it to automotive exhaust systems.
The idea is to tune out the drone at the source before it resonates and vibrates body panels and parts.

Simply put, it would be a kit that would form a ring which clamps around the exhaust pipe.
By rotating the position of the ring as well as selecting different parts of the kit, you find the right 'tune' that dials out and cancels the drone.


There is considerable R&D to be done before this could be made available, and DKF is looking for some input on a couple of things so that they can decide to proceed or not.

- Need; is there enough interest to develop this product?
- Cost; what do you consider an be equitable cost for a product that tunes out drone?

Trying to keep the poll simple, but please feel free to add comments re cost etc in the thread.

[inTgr8r]

Also....
Anyone with a Z4M in Tampa Bay area interested in test fitting DKF product(s) ????
Drop either Doug or G an email.

Giovanni Souza AKA Diokaef
souza.inc@gmail.com

Doug Davis
dkfperformance@gmail.com

[Nate4641]

One thing I think a lot of people would be worried about is weight. This thing could completely eliminate the drone, but if it weighs too much it wont sell.

Also it has to be easy to install.

I would definitely be interested. Love the sound of my RPIs, just not when I'm cruising on the highway.

[intoflatlines]

I put down that I'm interested at $200. But for that cost, it should actually greatly reduce my drone, not be something that "might" work for some people, or have only a small difference in drone.

If it truly cuts down my drone a good amount, I'd gladly pay $200.

I have a LOT of drone. If only they were closer to Chicago I'd stop by for test fitting.

[inTgr8r]

Originally Posted by intoflatlines

I put down that I'm interested at $200. But for that cost, it should actually greatly reduce my drone, not be something that "might" work for some people, or have only a small difference in drone.

If it truly cuts down my drone a good amount, I'd gladly pay $200.

I have a LOT of drone. If only they were closer to Chicago I'd stop by for test fitting.

Price is more of an outside limit... in all likelihood it will be less than than 200

This is intended to be MUCH more than a band-aide solution.
The idea is to be able to tune it out.
That's why its NOT a one size fits all cure all.
The buyer has the ability to tailor it to his particular exhaust.





LMAO.... just noticed I fail at spelling Anti- in the poll questions

[inTgr8r]

Originally Posted by Nate4641

One thing I think a lot of people would be worried about is weight. This thing could completely eliminate the drone, but if it weighs too much it wont sell.

Also it has to be easy to install.

I would definitely be interested. Love the sound of my RPIs, just not when I'm cruising on the highway.

There is definitely a little added mass.
The weight will be less than a lb.

[intoflatlines]

Originally Posted by inTgr8r

This is intended to be MUCH more than a band-aide solution.
The idea is to be able to tune it out.

What would it be? An adjustable helmholtz (sp?) resonator? How easy would the install/adjustments be?

Like I said, I have a lot of drone. It's so bad that I have earplugs in the car for if I do any highway driving. Above 4K RPM it sounds amazing though

[inTgr8r]

DKF is working on some drawings that will be posted.

[gmbbs]

If it's anything like the rest of a DKF system, weight is not a concern. thier system is a flyweight!

[inTgr8r]

[txz4]

i would gladly pony up 200 for something like this assuming it worked EXACTLY as advertised.

[Vanne]

I have drone while my engine is labouring, either due a wrong shift (too low rpm) or a lazy cant be arsed to shift down a gear.
How would this work? There are sooo many variants of pipe out there?
Very interested though.

[ga41]

200 bucks for RPI volume, pops and bangs but reduced drone? I'm in!

[Finnegan]

Sounds, no pun intended, like it could be a win. For example, I really liked my Diablos, but the drone was a deal breaker. Other cans are out there, but typically über-expensive. Such a product, if "tune able" to cancel resonance, would have more than a Z4 application. (S65 has the same tendency to drone.)

[Urluz3n]

"I have drone while my engine is labouring, either due a wrong shift (too low rpm) or a lazy cant be arsed to shift down a gear.
How would this work? There are sooo many variants of pipe out there?
Very interested though."

Just like mine
I would spend $500 if my drone goes away!

I installed a cat less header on my M Coupe a few weeks ago and then I had Active do a tune on my ECU. Now the drone is killing me! It seems to occurs always around 2000 rpms. I am considering exchanging my Stromung for my oem mufflers. Maybe the drone will ease up. Unless someone has a better idea.

[jophish17]

Don't drive at 2k rpm!

[Urluz3n]

It is not that easy

[StickMon]

I love my Diablos. I really don't get the drone thing.
I bought them so they would make a racket, and they do.
I guess I spent too many years driving a ricer with a FlowMaster.
(Think really big leaf blower.)
Maybe it's worse in the coupe than the roadster.

[Z4inAZ]

Yeah, take a car with a droning exhaust on a 2,000 mile roadtrip then try to tell us you still love em!!!

[intoflatlines]

I had to drive 2 hours on the highway to a remote office for work today. Luckily I keep earplugs in the car. I've got 2 more hours this afternoon :/

I'm hoping this product is legit and actually works. I would pay so much money to have the exterior sound of my exhaust without the incredibly terrible interior drone!

[Urluz3n]

Just changing out the mufflers doesn't necessarily give you a drone. When I just had my stromung mufflers I had a really good sound with no drone. Once I installed the the headers I got the drone.

[inTgr8r]

Discussions on drone often head down a few different paths as people often have a different idea of what drone is.

Drone is a high amplitude sinusoidal oscillation of the exhaust gases in the exhaust pipe.

A droning exhaust system works something like a single note pipe organ.
When it hits a certain frequency (e.g. ~125 Hz), it rings out loud and causes what is known as drone.
So the idea of an anti-drone product is to tune in to 'that' frequency and convert that energy to another form to cancel out the drone.

Drone is not just noise or a loud exhaust.