Had the 530i muffler installed in my 525i today.....wow

[Chris'91'525i]

If anyone wants a slight performance sound, I think this may be the ticket.
There were a few tense minutes after the shop cutoff my original (internally) rotted out muffler. The 530i muffler was about 3-4" higher in the back section and it was about 5-6" longer.
I thought OH S#it, this aint going to work. But it did mount up to the hanger clamps just fine. And they were able to weld the inlet pipes with no problems.
Car has a real nice exhaust note now and a definate perfomance increase from idle to WFO. Though that was probably due to the bad muffler that was on it.
Is the 530i a V8 motor, hence the mufflers larger size ?
Anyway, I'm a happy camper today !!

Oh, and they did not disconnect the cars battery or anything else while MIG welding. And all is good !!

[632 Regal]

the 530 is a V8 but the muffler size has more to do with cancelling sound waves at a certain frequency tuned to that engine hence it is louder in your 2.5, not tuned to that engine.

[ThoreauHD]

Yea, mine is pretty quiet.

[ILoveMPower]

How much did it cost to have a shop weld the muffler on for ya?

[Chris'91'525i]

How much did it cost to have a shop weld the muffler on for ya?

$110.
The PO of this muffler cut off the inlet pipe almost flush with the muffler, so the shop had to grind the original welds so he could pull them out of muffler, then he had to fabricate 2 new inlet pipes to muffler since this 530i muffler is about 5" longer than the stock one.
He could have simply just stuck the new inlet pipes into the nubs on rear of muffler, but this looks much more professional.
There are all kinds of tight bends and not much clearance, so it was a little more expensive than just welding two straight pipes together.

He also welded plugs into the welds on a couple small leaks when the the new catalytic converter was installed before I bought the car.

The OEM muffler was used one year by PO. I got it on eBay for $9.99 + $5 pickup charge, and a 75 mile RT to pick it up.
So it was about $135 total. I defiantly lucked out on this deal.
I love the sound and the performance. It's not real loud at all, but has that new factory performance car sound.
I like it !!

[TheEndIsNear]

Which muffler, the mid or the final... I need a new exhost after my run in with a tire today and that sounds like a great mod...

[Chris'91'525i]

Which muffler, the mid or the final... I need a new exhost after my run in with a tire today and that sounds like a great mod...

The main rear muffler, where the sounds comes out :)

I don't know if it makes a differance, but the aftermarket catalytic converter that was replaced the OEM unit looks much more compact.
I was just looking on realoem.com, and the newer one looks half the size of the factory unit.
Maybe newer technology makes them more efficient, or there's just a big heat shield on the factory one.

[genphreak]

The main rear muffler, where the sounds comes out :)

I don't know if it makes a differance, but the aftermarket catalytic converter that was replaced the OEM unit looks much more compact.
I was just looking on realoem.com, and the newer one looks half the size of the factory unit.
Maybe newer technology makes them more efficient, or there's just a big heat shield on the factory one.Most peeps treat their cats like "I hate the thing (it robs me of power), I'll put hte cheapest replacement on". I imagine the M20 is the same as the M30 (ie it has 2 'fat' cats) and you can bet a whole lot more than a Bush controlled future that BMW spent a whole bunch of time getting it right rather than wrong (as most others did around that era were with shitty ECUs and poor emissions components). Plenty of aftermarket engine pipes have a single cat and a y junction, use much smaller pipes bent with shitty benders that crush the tube reducing flow. The factory units are full 2-inch mandrel bent high grade stainless that last longer than the car and fit perfectly- the welds are superb. Replacement cats often suffer from crumby welds, poor parts, fitment etc so who knows how they perform. I'd always prefer stock with the cat, a replacement would need to be damn good to get a second look- in most cases second hand original would eb far better (and 1/4 the price)! :) Nick
Plus you get really decent heat shielding, so long as it isn't all chewed up and rattley.