Good exhaust system or not..?

[bwo1525]

I'm thinking of getting a new exhaust system from my buddies shop. It would be a magnaflow muffler, custom 2.5" or 3" (can't remember which one) piping, and take out the resonators. All this for around $250. What do you think? What do magnaflow mufflers sound like? I cant seem to find any sound clips. What performance gains to you think i will get on my 1995 325is?
Thanks

[STEVE36]

Little to no performance gain.

And I wouldn't recommend going with a makeshift Magnaflow type set up. Go ahead and pick up a known brand (not saying Magnaflow isn't, but BMW brands - ActiveAutowerke, Stromung, UUC, etc) full catback system with some 328/m3 cats as well and you'll be set.

[jmott]

nothing wrong with a makeshift setup. I have a cheap flowmaster welded to some cheap pipe.

my car makes good power (202rwhp from a 2.8L with bolt ons) and wins lots of races.

sounds great too!

[thejaff]

nothing wrong with a makeshift setup. I have a cheap flowmaster welded to some cheap pipe.

my car makes good power (202rwhp from a 2.8L with bolt ons) and wins lots of races.

sounds great too!

You already have the good cats. That's where he needs to pick up most of his power. With '96-99 M3 or 328 cats and just a stock M3 exhaust, you can get some decent power. Couple those cats with an aftermarket exhaust you can get those couple more that you are talking about.

[jmott]

Actually I had the OBD1 cats at first, and made like 198rwhp before getting things tuned right.

I did the tuning and removed the cats entirely later on and made 202rwhp

My reason for the ghetto exauhst is weight savings. It is like 30lbs lighter than the various stock catbacks

You already have the good cats. That's where he needs to pick up most of his power. With '96-99 M3 or 328 cats and just a stock M3 exhaust, you can get some decent power. Couple those cats with an aftermarket exhaust you can get those couple more that you are talking about.

[bwo1525]

Are magnaflow mufflers not good for performance? Does anyone know what it would sound like? I havent been able to find any sound clips of it. Why would this muffler with the custom piping not make any more power?

[jmott]

Are magnaflow mufflers not good for performance? Does anyone know what it would sound like? I havent been able to find any sound clips of it. Why would this muffler with the custom piping not make any more power?

the muffler isn't really a restriction in the exauhst system. so power wise it doesn't really matter which muffler you use.

only change it out from stock if you want the noise or weight reduction.

[bwo1525]

So what does make the difference? The cats? The piping?

the muffler isn't really a restriction in the exauhst system. so power wise it doesn't really matter which muffler you use.

only change it out from stock if you want the noise or weight reduction.

[Blufire]

Edge Motorworks uses Magnaflow mufflers in their exhausts, I think... and those are very good, VERY loud exhausts.

[thejaff]

So what does make the difference? The cats? The piping?

That's where the restriction is on the 323... 2 pipes---> 1 out of the cat---> 2 tips out of the muffler. When you think about it, it's actually a pretty dumb setup. That's why I'm replacing it.

[jmott]

From tunnel's site (he is in fact talking about the very flowmaster on my car now, thanks to an odd twist of fate)

"Last year I started running a FlowMaster cat-back exhaust that I had designed for the 97 (3.2l) M3 I roadraced in '98 and love it. Dyno results show modest gains in peak horsepower (+7hp) and torque (4-7 lb/ft), but I believe its greatest benefit to be in weight savings -- it weighs only 21 pounds."


"2003 update: I am now running a full header-back exhaust system with a high-flow cat and Magnaflow muffler. Dyno tests show no significan gain (+/-1hp) but by replacing the OE cats with a single high-flow unit and going to a single 3" pipe all the way from the headers, I've now saved 37 pounds of excess weight. And it's perfectly legal in Street Prepared as well as Street Modified."

this was on a 3.2L M3 though, which flows a lot more air than a 2.5, you might not get that 7ish HP

So what does make the difference? The cats? The piping?

[jmott]

That's where the restriction is on the 323... 2 pipes---> 1 out of the cat---> 2 tips out of the muffler. When you think about it, it's actually a pretty dumb setup. That's why I'm replacing it.

good for ground clearance, but thats about it.

[arakele]

I see nothing wrong with using a magnaflow setup, spending 700 bucks on a heavy catback is just not for me. (granted, I love the way most of them sound)

Magnaflow has dual in/out aluminized mufflers that work pretty well, and the weight savings are nice. Mine should be finished Saturday and I plan to have a sound clip.

Only thing I changed up from previous is using dual in/single out (all magnaflow's are designed to be reversible) with an oblong style tip. I normally hate single tip exhausts for an e36, but this will look similar to the oblong tip that ac schnitzer makes for the dual tip stock mufflers. I may change it up again and got back to dual tip but I will see on Saturday

[NegativeCamber]

Little to no performance gain.

And I wouldn't recommend going with a makeshift Magnaflow type set up. Go ahead and pick up a known brand (not saying Magnaflow isn't, but BMW brands - ActiveAutowerke, Stromung, UUC, etc) full catback system with some 328/m3 cats as well and you'll be set.

this is the type of false info you want to avoid. people seem to feel like they are getting a better deal on buying expensive brand names. yes, these bmw brands are good products, but because the muffler gains are minimal, a straight through design like magnaflow is still getting your moneys worth. it flows well and sounds nice.

[T-Rex]

this is the type of false info you want to avoid. people seem to feel like they are getting a better deal on buying expensive brand names. yes, these bmw brands are good products, but because the muffler gains are minimal, a straight through design like magnaflow is still getting your moneys worth. it flows well and sounds nice.

Exactly, I couldn't be happier with mine, and I'm also happy that I only spent $160 on it installed.

[T-Rex]

good for ground clearance, but thats about it.

Not even, they did it to restrict the output of the engine.

[Kevin325i]

Single magnaflow muffler with 2.5" piping. Custom made and welded by me. Total cost was less than 100 dollars. The only reason I did it was because I saved close to 20 lbs. The stock system was 58 lbs, my set up weighs 30.

I think it sounds like a fiero GT if it were revving another 2k rpms. It's not bad, but it is really raspy. I honestly think that the irridium plugs I got were more of a performance gain than this exhaust provided.

[STEVE36]

this is the type of false info you want to avoid. people seem to feel like they are getting a better deal on buying expensive brand names. yes, these bmw brands are good products, but because the muffler gains are minimal, a straight through design like magnaflow is still getting your moneys worth. it flows well and sounds nice.

False info? Where did I say anything about better gains than a Magnaflow?

I was commenting on overall quality. The overall quality of a higher priced catback such as the ones I mentioned earlier is greater than that of a Magnaflow type set up. Period.

The rest is personal preference. If you don't want stainless steel/a certain exhaust note/perfect bolt up compatibility/whatever, then that's fine. Depends what you want to do.

So to clarify, there was no false information in my post.

Steve

[jmott]

Based on what evidence do you make that claim?
why would anyone restrict the output of the engine?

if you wanted to choke off the exauhst you could do it with a small single pipe, and it would weigh less and cost less.

im pretty sure they did it for space reasons.

Not even, they did it to restrict the output of the engine.

[STEVE36]

Based on what evidence do you make that claim?
why would anyone restrict the output of the engine?

if you wanted to choke off the exauhst you could do it with a small single pipe, and it would weigh less and cost less.

im pretty sure they did it for space reasons.

To result in a "de-tuned" 325. All I know, however, is that stock for stock my car is faster than my friends 325.

[Blufire]

Based on what evidence do you make that claim?
why would anyone restrict the output of the engine?

if you wanted to choke off the exauhst you could do it with a small single pipe, and it would weigh less and cost less.

im pretty sure they did it for space reasons.

One reason to restrict the output is to differentiate it from the 328, i.e., make the performance gap bigger so people won't say "oh, you dont really get that much extra from the 328i, so way pay the extra money"

[jmott]

One reason to restrict the output is to differentiate it from the 328, i.e., make the performance gap bigger so people won't say "oh, you dont really get that much extra from the 328i, so way pay the extra money"

the 328 also has two pipes doesnt it?
the 328 also makes more power even with the same exauhst if you actually measure it on a dyno

yet they advertise them at the same power anyway.
so I dont think that is why

[jmott]

To result in a "de-tuned" 325. All I know, however, is that stock for stock my car is faster than my friends 325.

I see, so by restating the claim, we provide support for it.

[Blufire]

the 328 also has two pipes doesnt it?
the 328 also makes more power even with the same exauhst if you actually measure it on a dyno

yet they advertise them at the same power anyway.
so I dont think that is why

328 and 323 are not advertised at the same power... 170 hp vs 193 hp...

Jmott, there's not much "evidence" that anyone can cite here... this is all speculation as to what BMW's marketing intentions were.

[Builder2961]

What about this one its only 10 bucks hehehe

http://cgi.ebay.com/ebaymotors/ws/eB...tem=7987672386