Dronefactory
 

I´m feeling a bit on the wild side.. If I purchase this: https://www.ebay.com/itm/STAINLESS-CAT-BACK-EXHAUST-BACK-BOX-SYSTEM-FOR-PORSCHE-986-BOXSTER-2-5-2-7-3-2/151320114061?fits=Model%3ABoxster&hash=item233b61b 38d:g:hMEAAOSw0rRbfTkl#rwid

I guess I´ll get to experience a serious drone... Besides from that, doesn't it look quite ok? Looking for someting that flows better than OEM and less weight. This shoud be fairly light don't you think?

The plan is actually to elaborate with helmholtz pipes to manage the droning, and the linked system looks ok and at a prize that should allow experiments.

The Boxster I just bought last month has this exhaust. It does drone quite a bit. I would not want to go on long drives. I just use it as a weekend car for around town so I am okay with it. Sounds great above 5000 rpms.

One thing that I dont like and need to look into - the tips contact the metal protector lip on the bumper. Maybe there is some adjustment I need to figure out.

Great info! Can you confirm that it weighs far less than the oem exhaust?

I'm not a big fan of the dual tube tips, but still..

My thougt is that those catback systems with this design / price range are more or less the same, incl circuit werks. Am I wrong?

Vtx531,
Use studs on the Trans mounts and space the mount out using nuts and washers.. It will lower the tips from the rear bumper

I would imagine it weighs less but I never had a stock exhaust to compare to. It does look a lot smaller compared to pics I’ve seen. I also don’t like the dual tube tips if you mean how there is a tube within a tube.

I will say the welds and quality seem pretty good. No rust on the stainless steel unlike a Magnaflow catback I had on my Jeep but that was driven on salty winter roads.

Im not familiar with exactly what you mean but I will take a look and see. Thank you

The eBay manifolds and exhaust are quite a lot lighter than the OE items. If you do the eBay exhaust and manifolds as you have linked recently then you should get a small increase in power and torque. First line is standard baseline run. Second line is manifolds an exhaust. Same Dyno same operator.

https://i.imgur.com/dUUCHnT.jpg

When you get under the car you will see that the exhaust is supported by a bracket that is attached to the rear of the transmission, if you lose the ALL the bolts at both sides you should be able to move the exhaust a bit and fine tune it's position, you may want to apply something like PB Blaster to the hardware a day or so before to loosen the rust, etc.

God luck!

Okay thank you

Before I go ahead, do you guys see any other better choices? I'm after a light and open catback at a reasonable prize. Already bought the headers & 200cel cats.

Related question, anyone actually built a helmholtz resonator to manage the drone? Care to show & tell?

Many thanks edc! You are one of the few that actually show dyno figures, very nice!

Yes there's lots of theorising but few if any other Dyno plot showing the various mods. Anybody can bolt these things on and say it feels like 15bhp or how they now pass this or that car.

What are top two lines? I wonder how much of the gain is attributable to the manifolds and how much is the exhaust? I have 01 with manifold/cat combo so I think I can only do the exhaust.

One set of plots is torque the other power. First line base line, 2nd exhaust and manifolds, 3rd 996 TB, 4th remap.

Hi all-

I am chasing this very issue as we speak...

Instead of buying the exhaust mentioned above, I went the easy route and got the second cat bypass pipes first as I heard they can help eliminate the deadly drone. The second cat bypass pipes gave some tone? But overall very very quiet.

After driving for a day drone free but wanting to hear more of that Porsche sound from the 3.2 (2002 S), I had a set of new magnaflow magnapacks in the box from a old jeep build and brought them down to a local exhaust shop to drop the suitcase and throw these in instead. We ended up getting them in and had the two cans meet before exiting out into new aftermarket tips.

The result? LOUD! Dare I say too loud! For the first time in my life, I knew the exhaust was too loud and needed something to be changed. I drove for a few days with one long trip and the drone from 2200rpm to 2900rpm was so loud I got I headache literally within an hour heading to Tahoe and had to get ear plugs.

I went back to the shop and thought I could capture the drone with a set of 12 inch glasspacks in the middle of the second cat bypass pipe... this did not change a thing in dB or drone...

So back to the drawing board... read online a good bit and found the flowmaster Hushpower 2 muffler... they also make the DBX in a 14 inch body which we are going to try in favor of the magnaflow resonators and then move the HP2 mufflers back in place of the 12 inch glasspacks.

I replaced the magnaflows with the HP2 quickly to see if it would cut down on noise which they did but the drone is still there.

Here are my solutions to fixing drone as the tone and sound of the exhaust with the HP2 mufflers is really great- better than the Magnaflow packs for sure.

1. See if DBX 14 mufflers can fit in place of 12 inch HP2's
2. If DBX dont fit, install a second set of HP2 instead of 12 inch resonators = 2 sets of Flowmaster HP2
3. Check drone on highway. If drone is too unbearable, install Car Chemistry baffles OR see if we can install a cross over pipes before mufflers or between both sets to capture more of the killer Hertz.

Only two solutions I found online: Car Chemistry baffles in tail pipes of I found someone that installed two turbo mufflers before tailpipes and that user found that his set up was drone free.

Kinda stinks having to put more restrictions in the exhaust but car chemistry bafflers are like motorcycle baffles and the HP2 mufflers emulate this while maintaining a laminar flow set up.

I am hoping two more HP2's will kill it or the DBX 14's will suffice... its the flat 6 motor and short amount of exaust length that cause the drone. I am experimenting because it will still be lighter than stock and the flowmasters sound pretty dang good.

Will update soon! Heading to shop this coming Wednesday to further experiment.

Glasspacks and HP-2 mufflers did bump up my avg MPG over the last 3k miles. sitting at 22.2 mpg on the dash. No dyno impressions but sound and performance is what I am after.

Sidenote: some people have mentioned using a WRX muffler. The muffler design has two side inputs and a center out for the tips... just another idea as this design is closer than anything to the stock muffler design.