Fleabay cat back muffler?
 

Hey Guys,

I'm thinking of adding this El Cheapo muffler to my 1998 base Boxster..... But am worried about the dreaded drone between 2000-3000 RPM (I know a Boxster should NEVER be driven below 3000 RPM!) I have read that some fellas have had good luck putting motorcycle Baffles in one or both muffler intakes....

I really just want a bit more sound.... And have desnorkled.... And was considering the Crios mod..... But kinda want to leave it in stock shape.... I figure for a $250 gamble life won't end if I don't like it..... But will the baffle idea work? Is it a bad idea?

Thanks!
Fred

https://www.amazon.com/Porsche-Boxster-Catback-Muffler-Cat-back/dp/B0042LLELW/ref=sr_1_5?ie=UTF8&qid=1512653177&sr=8-5&keywords=Stainless+cat+back+exhaust+Boxster

This muffler is sold under several different brand names around the interwebs, and yes, some owners have reported droning (mostly while cruising at freeway speeds). Do a search, there are a lot of posts and several different approaches to reducing or eliminating the drone.

Whether any particular drone "fix" will work for you is impossible to know because everyone has a different perception of drone and what level is acceptable and/or bothersome. This is an instance where "your mileage may vary" is a truism.

If you can afford a $250 gamble that might not pay off, then I'd say go for it because the exhaust will sound 100% better.

Hey Guys!

I think I am going to try one of these.... But I think a motorcycle baffle (or two)
May be the ticket to nice sound... But no drone.....

Does anyone know what size pipes the inlets are on the fleabay mufflers????

This is the kind of baffles I am thinking of trying....

https://www.denniskirk.com/khrome-werks/2-in-hp-plus-drag-pipe-baffles-202032.ph44563.prd/H44563.sku

i'm not sure why there's different reports.....from no drone to unbearable. I know everyones definition and tolerance is different but still.
2.7 engine 2ndary cats delete pipe and ebay 200 buck exhaust and I don't have any drone. It's a little louder than stock but nothing obnoxious. I wish it was more high pitched but it is what it is.

It seems like people that did the muffler only have drone but one's that did 2ndary cat delete combined with the muffler have no drone...just what i've observed

I just, last week, purchased the exact muffler but will install only in the spring. Please let me know what you did to alleviate the drone. The pipes are 5.5cm. I don’t know if I while have any or not, but knowing what you dud might be of help. Thank you!

I did the motorcycle baffle in a GHL boxster exhaust. It did help the drone that was really bad.

http://986forum.com/forums/uploads02...1512791942.jpghttp://986forum.com/forums/uploads02...1512791977.jpg

Just my .02. IMHO I think it is counterproductive to purchase a free flowing exhaust only to restrict it with baffles. I'm by no means an expert but I did some research on the issue while trying to quiet high compression big block engines. The drone these things made was crisp, high pitch and ear bleed loud at cruising speed, at 6500 rpm? Glorious. Even 70 series Flowmasters designed to quiet motorhomes wouldn't help.
What I found is that drone is caused by the uneven firing order between banks causing unequal pressure pulses in a true dual exhaust that creates a harmonic distortion kinda like "clipping speakers" to your ears. To address this there are balance tubes and the Gas X crossovers that even out those pressure pulses between banks. This is not possible in these cars and is why the stock muffler has the balance tube inside it. But yes it's heavy. We really need someone to think outside the box and come up with some sort of crossover for these cars, but the additional pipe may negate the weight savings. Otherwise it's modifying the stock muffler although I think as bypasses get larger then drone will also start to increase. Porsche created the PSE so it can be loud when mashing the pedal and quiet when cruising, but it's even heavier with the additional piping and valves. Good Luck.

Oh Yeah in case you were wondering what happened to the noise of the big blocks? With the simple addition of the balance tube the sound went from the ear bleed loud to a nice mellow rumble. It was truly remarkable.

Thanks guys!

I almost wonder if a bypass pipe run pre muffler.... Would work best to tame the drone in these Chineasium mufflers. I'm also Not sure if motorcycle baffles would work best upstream of the muffler, or down stream in a conventional "tailpipe" location.

I guess I will have to get the muffler in figure out what size baffle to get.....

03S..... Do you recall what size you used?

(Thanks for posting your picture.....makes me think I'm on the right track!)
Maybe I should just "cool my jets" until I get my muffler installed.... And then see how they sound.....

Fred, please let me know what you find out in terms of droning (if any), and if so, if you remedy it with baffles, which ones you used, and where you positioned them for best effect.

As mentioned, while I received the muffler, the Pcar is stored for the winter so I can’t install it until April. But i’d like to be all ready.

I’ll have it install on the same pcar as yours, btw: 1999 base.

Incidentally, i inspected the muffler when I received it last week and was happily satisfied with the workmanship (same exact one as from your link, from same vendor). Very nice and solid welds, if that is any comfort to you. Looks good too (nice and polished).

Why not try a balance pipe joining the two boxes.

So I installed mine. Easy installed but there is a strong drone (to me) between 2000 and 2900 rpm. Not at highway speed however. Super nice sound below 2000 (idle) and glorious above 3000. I have the 2.5l.

So to handle the drone, I just purchased 2 baffles and will install this weekend. Will report back. If it does not work, I’ll have to go back to the OEM muffler. I might try before a connecting pipe too.

Fred, how did it work out for you?

Cheers.

All right. So I installed 2 baffles, one In each of the intake pipes (into the fleabay mufflers). The drone is 85% gone. It seems only to exist at 2000 to 22`00 rpm (while it used to be from 2000 to 2900 rpm). So much, much better. I need to tightens the bolds more as I have a air leak.

Not sure if I will keep it, however. I might go back to OEM. Seems a little too loud for me. I’ll drive around a little more and decide. Cheers.

Update. Today I took off the aftermarket muffler and reinstalled the OEM. I am getting quite good at this. Of course I remove the bumper to make my life easier.

I did this because I was worried my neighbors were less appreciative of my new sound. My wife felt I was overreacting but I wanted peace.

So, wow, the OEM is very quiet in comparison. All and all, I would reinstall the aftermarket muffler if I decide to track it because it is more high flow and the drone is 95% gone, but will for now stay with the OEM. I tried to crios mode but could get the drill bit to bite. Oh well.

Post #307...something to consider. ;)
https://986forum.com/forums/diy-project-guides/19770-diy-exhaust-mod-%96-gain-10-hp-16.html

Local muffler shop charged me $20 to weld small plates over the shell holes.
Has a decent growl at idle up to about 2700rpm. 3000rpm and up really howls. No significant drone. Neighbors happy, wife happy, I'm happy. :D

I had the exact same experience with the ebay muffler. Ended up taking it off the same day. Sounded crazy above 3k with my cat bypass pipes but way too much drone. A short drive gave me a headache.

I had that problem too...

The drill bit caught just fine after punching a hole in the pipe first.

Boxstersteve,

Do you have a base? Because this is what I have and it seems to be a slightly different process to do the crio mode on a base, or is it?

As far as I know, the only difference is the cosmetic muffler tip.

Installed a circuit works Ebay special muffler last night. OMG :eek: the drone between 2000-3000 RPM's is insane. It sounds like I have a pipe organ playing 50HZ sitting between the roll bars. I know one of my clamps is leaking, I have some new ones on the way. I guess when they come in i'll try to throw a baffle in one side and see what happens. My wife said when I left the house this morning is wasn't too loud and sounded cool. But if she heard it in the car she would leave me lol. I hope between the new clamps and baffle it calms down a little. On my test drive there were police all over the place. I thought for sure I was going to get pulled over for no muffler.

OK I was getting sick of the drone after 2 days. So i grabbed a big breaker bar and tightened all the clamps. I was surprised how much more I was able to tighten them with more leverage. I'd say the drone is 75% gone now. It is still really noticeable between 2,800 to 3,100 RPM's. Of course that's about 65 to 75 MPH in 5th gear. My next step is to install a baffle in one side. I'm not sure where i'm going to put it yet. I have a few more day until my new clamps get here.

Just to recap. I have a 98 base. 5 speed. One pair of cats in the mid pipes. Stock exhaust manifolds.