Straight Pipes

[teen ti]

I'm looking to straight pipe my '97 318ti and was wondering how difficult it would be to do the job myself, any and all comments are appreciated

[spidertri]

Do you know how to weld?

[teen ti]

i can weld to an extent, if i just need to make it attach i can do it well enough, although would it be easier to just delete the muffler and pipe it from there?

[318_mzk2]

But the pipe 20-40 12ft bucks take it to mineke or Midas 150 or less they bend it and weld it done deal...

That's what I dis w mine

[cooljess76]

Why would you want to do this? What are you trying to accomplish?

[teen ti]

i'm doing this to achieve results similar to a sport exhaust system that would run me $400+ for considerably less

[318_mzk2]

Free flow exhaust??? .

Are you changing pipe size.. Cat delete? Res delete?

[teen ti]

i'm gonna keep the size the same and at the very least delete the muffler but will most likely delete the cat and resonator

[318_mzk2]

Ok.. So no need to actualy bend pipes .. Get an aftermarket exhaust ..2 pipes 2 1/4in
Cut cat/ cut res

Weld pipes.. Or like I said take it to a shop it won't b more than 100 bucks.. I'm sure in ny there's gotta b cheap shops

[teen ti]

i've got better than cheap shops, one of my buddies' dad has a shop and they did a straight pipe on his '91 318is so i'm hopefully gonna get help from them

[318_mzk2]

There u go lol.. I did my exhaust 2.5 in header back cat/res delete to a 2.5 brola exhaust for 240 everything

[teen ti]

sounds like a good deal

[318_mzk2]

20 for a 12ft 2.5 pipe.. 100 for labor 120 for the exhaust

[teen ti]

thats not bad at all, and hopefully the labor won't cost anything seeing as that i'll do it with my buddy

[cooljess76]

i'm doing this to achieve results similar to a sport exhaust system that would run me $400+ for considerably lessAn aftermarket exhaust system only has two benefits for these cars. The first and most obvious is sound. Straight pipes will not accomplish this. In fact, it'll just make your car sound like a riced out piece of crap, thus making you look like a doucher everywhere you go. The only other benefit of aftermarket exhaust is weight savings. The stock exhaust is rather bulky. However, it's positioned in the best possible spot for something of it's size and weight. Low and over the rear wheels. If your goal is weight reduction, there's about a dozen other things that could be addressed before ghettofying your German engineered auto with some cheap ass hillbilly bs.

A NA 1.9L 4 banger is not going to growl like a V8 no matter what kind of exhaust you're running. If anything, there's only 2-5hp max to be gained by installing a QUALITY aftermarket exhaust that has been designed and engineered specifically for our cars. However, whatever you gain on the high end, you're sure to lose on the low end. So while your engine may "breathe" better at high RPM's, it'll "gasp" at low RPM's. In other words, you'll lose low end torque which will cause your car to be sluggish off the line.

Are you considering deleting the catalytic converter? If so, keep in mind it's a $1500 part. So right off the bat, you're decreasing the value of your car significantly. Besides being illegal, your car will not pass inspection and potential buyers can sue you if you do not disclose the fact that you've deleted a critical part of the vehicle's emission system. Before you say that your state doesn't test or you know a place that will cheat the system, it's a FEDERAL law. The EPA is a federal agency and regardless if certain states test, removing or altering any part of a vehicle's emission system that is to be driven on the highway is illegal and punishable by healthy fines and/or possibly jailtime.

Let's say you ignore what I've already layed out and you decide to do it anyway. So now your car is annoyingly loud, runs like crap since the o2 sensors aren't giving ACCURATE readings and the engine is running too lean or rich aside from being a slug off the line from loss of low end torque, resale value and fuel economy have gone out the window since nobody wants to buy a car from some teenager who has molested it with ghetto/hack mods and the only attention you'll draw aside from the cops will be people looking at you thinking you're just some cheap ass idiot teenager driving a de-valued BMW. All so you can THINK you're cool when you tell your friends "my BMW has straight pipes...":rolleyes:

Your car is not going to be any faster and you're not going to look any cooler. But hey, do what you like, that's just my opinion.


BTW FWIW, there's been reports from people with supercharged 318ti's who tried running 2.5" catbacks, only to find out that they lost a significant amount of low end torque. That's with a FI setup, imagine how a free flowing system will affect a NA motor.

[1996 328ti]

I had an exhaust which basically was non-existent. No packing material.
The car sounded like crap.
Rather, the car sound obnoxiously loud. I couldn't drive it through my neighborhood without being embarrassed and driving on the highway gave me a headache.
I replaced the muffler and now I have a s/s paperweight.
I don't know how different an M44 would be compared to a M52.
Doesn't an exhaust system need some back pressure?

[tiFreak]

I ran no muffler on my track rat, now it has a Cherry Bomb glasspack, sounds like crap, if it was a street driven car I'd definitely be running a real muffler but it's fine for a track rat

[cooljess76]

I should add that a custom fabricated catback exhaust with a nice magnaflow muffler can be had for a couple hundred bucks. IIRC, the magnaflow mufflers run between $75-$100 and most muffler shops will custom bend/weld an exhaust system for another hundred or so. It doesn't cost that much more to do things right, maintain performance and longevity of your engine and remain legal. I highly suggest keeping your factory cat. Most if not all aftermarket cats fail prematurely. The factory cat costs about $1500 for a refurbished one. If yours goes bad and you can't afford an OEM replacement cat, you can always pick one up from someone parting out a car on the forum. Junkyards are not allowed to sell used cats, so your best bet is a private party.

[Mr. Crow]

Who thinks I should put my resonator back in?

My thinking was that the DASC would perform better without it.....I really cant tell anymore if it performed better with or without it. I just know its obnoxious. Im not embarrassed about it however.

Running 2.5 from the cat to the exhaust, custom weld....it's sounds very tuned and throaty!

eh well, kids will be kids!

[xxxJohnBoyxxx]

I run two resonators and a flowmaster. Sounds great and no drone.

Straight pipes suck balls.

teen ti ~ I know you think it will be faster and sound cool but it won't. It will sound like a Yugo with no muffler and perform worst then it does now.

Please use your head for something other then a hat rack on this project.

[19742002tii]

Some of these guys were a little harsh. Many have gone through this phase, just look at all of the "performance" exhaust systems available. Some sound good, some not so. Your best bet is to leave it stock. It is what it is, an economical fun little car. Good luck.

[teen ti]

thanks for all your suggestions, i suppose in this light striaght pipes are a poor idea, i knew that there would be no performace gain whatsoever but i was hoping to achieve a better sound, seeing as that i had a friend who did it to his '91 318is (yes i realize they are different engines) which did not sound ricey at all and was not very loud but rather low and throaty. seeing as that i have a rather limited budget i figured straight pipes were the way to go, i suppose if i could find a decent aftermarket exhaust or muffler i would be comfortable with that, therefore i would appreciate ideas on an exhuast or muffler to put on

[cooljess76]

i'm not worried about the value of the car whatsoever seeing as that i have no plans to sell it and its not exactly what you would call a valuable car in the first place despite having been optioned with everything possible with the exception of seat warmers. even if i do follow through with this i will probably just do a muffler delete and keep the resonator and cat. the only reason i considered straight pipes was because i had a friend who did a straight pipe on his '91 318is and itCool man, hey it's your car so the only opinion that matters is your own. I'm just saying, if possible save your old parts and don't hack things up because someday you'll probably regret this and want to return it to stock. There's no real performance or sound improvements to be had here. If your goal is a cheap and obnoctious sounding car, then straight pipes should achieve just that. My intentions were not to sound harsh, but when you say that you're "trying to achieve similar results as a sport exhaust" by hacking off your muffler and welding a pipe... Well one can see how this is somewhat comical:chuckel:

[teen ti]

don't worry about sounding harsh, if anything its beneficial, i'm just trying to accomplish the impossible, make my car sound decent for cheap, i like the sound of the ansa sport exhaust but that would run me close to $400 and while i do have plenty of cash to cover it i'm going to college in a year which will cost me over $35,000 a year and am looking to purchase another car, such as a 328is, on top of all this i've got an autotragic tranny which accomplishes nothing more than pissing me off and i figure if i could enhance other parts of the car i'd feel a little bit better about it

[xxxJohnBoyxxx]

thanks for all your suggestions, i suppose in this light striaght pipes are a poor idea, i knew that there would be no performace gain whatsoever but i was hoping to achieve a better sound, seeing as that i had a friend who did it to his '91 318is (yes i realize they are different engines) which did not sound ricey at all and was not very loud but rather low and throaty. seeing as that i have a rather limited budget i figured straight pipes were the way to go, i suppose if i could find a decent aftermarket exhaust or muffler i would be comfortable with that, therefore i would appreciate ideas on an exhuast or muffler to put on

If you like the way the 91 318is sounds then copy what he did. It is your car and what matters is what you like, your car is your style and when youu drive that is what people think of you. If it is the sound you want then do it.

[teen ti]

If you like the way the 91 318is sounds then copy what he did. It is your car and what matters is what you like, your car is your style and when youu drive that is what people think of you. If it is the sound you want then do it.

the only thing stopping me from doing that is i'm unsure how the different engines would effect the sound as well as how i would get by the legality of the thing

[cooljess76]

thanks for all your suggestions, i suppose in this light striaght pipes are a poor idea, i knew that there would be no performace gain whatsoever but i was hoping to achieve a better sound, seeing as that i had a friend who did it to his '91 318is (yes i realize they are different engines) which did not sound ricey at all and was not very loud but rather low and throaty. seeing as that i have a rather limited budget i figured straight pipes were the way to go, i suppose if i could find a decent aftermarket exhaust or muffler i would be comfortable with that, therefore i would appreciate ideas on an exhuast or muffler to put on

I recommend Magnaflow, they have many different configurations as far as inlet/outlet diameters, tips etc. There's a sound clip thread floating around the forum, a lot of members have used magnaflow mufflers with good results. xxxJohnBoyxxx said he likes his Flowmaster, another reputable brand and 318_mzk2 recommended Borla. You can pretty much use any muffler, just find one that suits your taste in sound/looks and have it welded to your catback. I'd recommend using the flange off of your original catback so that it'll remain removable from the catalytic converter. 2.5" piping might be a little too free flowing for a NA 1.9L. Some members have used it without any noticable losses, but others have complained about decreased low end torque. I'd recommend 2.25" piping bent/welded onto a Magnaflow 14809 or 14816:
http://www.youtube.com/watch?v=hX-S8t6oIOs
http://www.youtube.com/watch?v=lgbLwReVHBs

[teen ti]

another idea i considered was trying to put the same ansa exhaust on that my dad has on his '70 1602, however i have no idea if it would fit and how well it would fit seeing as it is a center tip exit and is dual tipped

[cooljess76]

another idea i considered was trying to put the same ansa exhaust on that my dad has on his '70 1602, however i have no idea if it would fit and how well it would fit seeing as it is a center tip exit and is dual tipped

Just about anything can be made to fit. There's step-up and step-down adapters, however I wouldn't recommend using a muffler with a smaller inlet. You may or may not want/need to trim your rear bumper opening. Most muffler shops will know what to do as far as mounting the hangers and bending/welding the pipes. Basically if you walk in and hand them a muffler, they'll put it on your car. Now your dad's 1602 might have a smaller inlet, so you probably won't want to do that as it may be too restrictive.

[teen ti]

so i like the magnaflow 14809, the muffler itself costs about $115, but i would like to have an approximation on how much everything else would run me

[cooljess76]

so i like the magnaflow 14809, the muffler itself costs about $115, but i would like to have an approximation on how much everything else would run me

Talk to your local muffler shop. Sometimes they'll have blemished Magnaflows for a little cheaper.

[318_mzk2]

have your friend weld the magnaflow exaust and thats it..

i had 3in inlet/3 outlet and i had to remove it cuz of how lout the thing was w my 2.5 header back..

aslo i have the m50 in my car not the 1.9.. i remember when i hadt the 4 banger i had done a vibrent exhaust ..cut my stock mufler and wellded that one in ..it sounded pretty good..

[teen ti]

ok then, sounds like i should be able to do this for a fair price and have a good result, which is much better than straight piping

[hicksr8]

ok then, sounds like i should be able to do this for a fair price and have a good result, which is much better than straight piping

If I were you I would do 2 1/4 straight pipe to a decent muffler, and that should fullfill your straight pipe obsession lol- j/k but for real though, thats what im doing, and it will be good... Ive already tried the straight pipe from the cat back with no muffler, and once you hit like 3000 rpms it sounds like an open honda header, and we dont want that.... :rolleyes: But try that out and your sure to like it....

[teen ti]

haha, defintely don't want to sound like a rice burner so thats the route i shall be taking

[xxxJohnBoyxxx]

Dude don't let these people change your mind. Go straight pipe!!!

If you don't like it you can always add muffler and resonator to calm it down.

I'm not being a smart ass but if you liked your friends 318 open straight pipes then do yours the same.

When I was young I uncapped my pipes on my Buick at home and had the cops there in 10 minutes. They left right away since they saw my dad already kicking my ass. I still enjoyed it. Do what you want, it's your car. Add the muffler and resonators when you want to sound cool and get the hot chicks. It's only a little extra to add parts but a lot to already buy them and remove:wink:

No sarcasm just honest. Don't listen to us old farts. We think we know it all but we really somethimes enjoyed learning on our own

[teen ti]

Dude don't let these people change your mind. Go straight pipe!!!

If you don't like it you can always add muffler and resonator to calm it down.

I'm not being a smart ass but if you liked your friends 318 open straight pipes then do yours the same.

When I was young I uncapped my pipes on my Buick at home and had the cops there in 10 minutes. They left right away since they saw my dad already kicking my ass. I still enjoyed it. Do what you want, it's your car. Add the muffler and resonators when you want to sound cool and get the hot chicks. It's only a little extra to add parts but a lot to already buy them and remove:wink:

No sarcasm just honest. Don't listen to us old farts. We think we know it all but we really somethimes enjoyed learning on our own

haha the only reason iwanted to do straight pipes was because i figured it would be the cheapest way to make the car sound better, however i do like the sound of the magnaflow much better and the price on that isn't anything too outrageous so i would much rather go that route bur thanks for supporting the idea of striaght piping

[xxxJohnBoyxxx]

haha the only reason iwanted to do straight pipes was because i figured it would be the cheapest way to make the car sound better, however i do like the sound of the magnaflow much better and the price on that isn't anything too outrageous so i would much rather go that route bur thanks for supporting the idea of striaght piping

I ran Magnaflow on my M44 stock motor and it sounded excellent with 1 resinator = 40% noise. I break down a BMW 318 exhaust like this:

1. cat converter 1/3 noise reduction 30%
2. resonator 1/3 exhaust reduction 30%
3. muffler 1/3 exhaust reduction 30%

10% left for you to hear on a stock BMW

Remove any peice and you see the increase in exhaust note.

I started with a straight 2.5 from header to magnaflow and it was loud and droned on the highway. Then I added a resonator and all was good. increase exhaust to 3" and you need to add more resonators.

[teen ti]

I ran Magnaflow on my M44 stock motor and it sounded excellent with 1 resinator = 40% noise. I break down a BMW 318 exhaust like this:

1. cat converter 1/3 noise reduction 30%
2. resonator 1/3 exhaust reduction 30%
3. muffler 1/3 exhaust reduction 30%

10% left for you to hear on a stock BMW

Remove any peice and you see the increase in exhaust note.

I started with a straight 2.5 from header to magnaflow and it was loud and droned on the highway. Then I added a resonator and all was good. increase exhaust to 3" and you need to add more resonators.

good info to know, thanks

[Mr. Crow]

I would agree with johnboy and Jess, your car is your own. Do what you please the only one driving it will be you.

With respect to custom weld exhuast system, I purchased the Magnaflow S/S Race series 14828
http://www.magnaflow.com/02product/shopexd.asp?zone=main&id=8761

I have a DASC with resonator delete and ran 2.5" piping. Any bigger than that is unessessary and too big. With that alone Im sure will annoy people, but more so strike people as "WTF was that?" I always ask people if it sounds ricey. Suprisingly the response is "not really"

The truth remains, Im running on 4 cylinders. Any exhuast you apply to any 4 cylinder car will be classified as sounding ricey in most people's viewpoint. Especially to other european car fanatics. The other truth is that you do not have a rice rocket, you have a german machine! In our arena, the tastfull mods are the most respected!

I was in a similar situation such as yourself a few months back, aftermarket systems can be pricey. Or you can go racedog way and have a custom weld job done at a fraction. In which is what I +1 on.

Let us know how it turns out dude, we all love pics, we all love video and we all love to BS about ti's.

AMEN!
And good luck my young friend!

[teen ti]

i know exactly what you mean mr crow, we do have 4cyl cars but at least they've got good suspensions and rwd and because of this i can outrun mostof my friends cars that have around 200hp soft suspensions and fwd, on the track at least :tongue: and therefore am not worried about a reasonable new exhaust system