Want to quiet down a straight 2.5" to magnaflow

[Earendil]

Is it just me, or are exhaust systems some of the most inexact and voodoo systems on our cars?

I had a rusting out system on my track rat, a 325i with a bone stock M20, and had the option to put a catless 2.5" back to an Magnaflow 14815 (single in, duel out). Cheap and loud, and when it's on the track sitting between 3K and 6K it's amazing.

The problem I've come to find is that it's also loud as waffles with extra syrup when it's just idling in my drive way. Below 2K I feel like I need to hang a sign out when leaving my neighborhood that says "I'm not really an asshole!".

Ideally I could cheaply quiet this thing down at lower RPMs, and still be loud up high. I don't care if it "sounds good". Alternatively I'll quiet the entire thing down, though I'd like to not lose any HP in the process.

So how would you guys go about doing that? Would it be cheaper to just switch mufflers, or to add something inline? Is what I'm requesting even within the realm of exhaust voodoo without spending a grand swapping around setups until something "just works" ?

[AwakenNoMore]

add a high flow cat

[deutschman]

Glass pack center worked well with all the Magnaflow mufflers I have used. Quiet down low but gets loud up high.

[Earendil]

Any suggestions on model, or are all glass packs created equal?

[Earendil]

Runner up question: on a 0-10 scale, 0=stock sound and 10=straight pipe to magnaflow, what do you think a glass pack addition in the middle would bring me down to?

Edit: a SWAG answer is completely acceptable, or or range like "5 to 9" or something. Just trying to get some sort of idea what I'm in for.

[deutschman]

Iv used a Cherry bomb and a Summit glass pack. The Cherry bomb was a bit deeper and raspier while the Summit unit sounded more like a ricer.

This was a 325e with an all stock motor, stock heads, Summit glass pack to Maganaflow single in and out with stock tubing size.


This was a m20b25 with a 272 cam and head work, MSDS headers, 2.5 piping, Cherry Bomb glass pack to Magnaflow single in dual out.
Its in a garage so it sounds a bit louder than it would outside.

[jllphan]

not to thread jack, but I'm in the same boat, M20b25 w/ headwork, 272 cam, 2" dual exhaust, two cherry bombs and magnaflow 2 in 2 out and it's just too damn loud. The drone at 2k is beyond tolerable. I'm contemplating resonators or a new muffler. anyone have any suggestions for the both of us? would glass packs be the ticket instead?

[deutschman]

Tuning an exhaust is really not so easy. Companies spend lots and lots of time getting their cars to sound good, but still be daily driver friendly.
Hopefully some one with a nice sounding yet quiet exhaust set up that is tried and true will chime in.
If I were to build another system I would most likely use an electrical cut out so I could run two systems in one. It would be a bit more pricy, but it seams like the most effective way to do the job. I mean even the new BMWs have vacuum operated exhaust shut offs that open up and make the car louder when you step on it, and then close up for slow driving and make everything nice and quiet.

[Earendil]

I don't care about "good sounding" so much as quieter, especially at quieter at idle and low RPM.
High RPMs can be as loud as waffles, as the car I lu sees that at the track. I just want to be able to escape my neighborhood and tune in my driveway without missing people off or making dogs whine.

Sounds like the best (cheap) option is to stick as long a glass pack in line as is possible. Something like this product: http://www.magnaflow.com/02product/02glasspack.asp
Goes for around $40 too.

[deutschman]

Yeah a long glass pack or a high flow cat will do a lot. You can get some cheap Summit brand V band clamps and weld them to the glass pack. That way if you dont like it it is really easy to stick something ells in its place and all you have to do is buy two v band circles. Pop in and out. They are only about $30 on Summit and work really well.