Custom Straight pipes, thoughts?

[Zeke]

Im thinking of taking my car down to some shop and having them weld some pipes to the old mid pipe mounts so i dont have cats (its just straight from headers to exhaust section). I know this is basicly the same thing as normal mid pipes, and will cost me very little. Does anyone know if this will stink the shit out of my car? and will it be much louder?

[Serious]

ya its going to be loud.

[Bernanke]

its not a bad idea but if you do it i would suggest X-pipe or H-pipe to help maintain low end torque while still giving gains on top end. You can modify a stock cat mid section and just cut the cats out of you want and put in high flow resonators. if you remove resonators it will make the car a little louder and more burbly but exhaust still does majority of the sound deadening resonator does less and cats really only affect sound above 4krpm.

[badmonkey]

I'm no tree hugger, but...

Straightpipes don't belong on the street, you gain precious little compared to the increased emissions.






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[Zeke]

i love my borla exhaust (the tone is perfect throughout the RPM range). Only problem is i would like it to be louder. Im thinking cutting out the cats will do this.

[GotBHP?]

i love my borla exhaust (the tone is perfect throughout the RPM range). Only problem is i would like it to be louder. Im thinking cutting out the cats will do this.

Cut out the resonators first. Its going to be really really loud with just straight pipes. You drive a street car, keep the cats.

[///M P0WER]

I'm no tree hugger, but...

Straightpipes don't belong on the street, you gain precious little compared to the increased emissions.






................

I agree

[GotBHP?]

Just because you can get away with it doesnt make it right. All that for maybe 5 hp....doesnt add up to me.

[Bernanke]

do you think being penalized for something just b/c of where you live is right either? it depends on your perspective on things

[///MacDaddy]

I'm no tree hugger, but...

Straightpipes don't belong on the street, you gain precious little compared to the increased emissions.






................

I agree....I assume you're looking for some gains. Go with OBDII mid pipes, keep the cats.

Yes your car will smell with no cats.

Check this out for a comparo on OBDI/II mid pipes.

http://www.rogueengineering.com/Merc...gory_Code=CATS

[beatniks325]

one more tally for the tree-huggers.

here in my area of WI we have no emissions testing at all, but i wouldn't remove the cats just because i could do it without getting in trouble on a daily driver. SupaBimma is right in saying the system isn't perfect.

there are always highflow cats but that adds to the cost of course.

[Hammdy]

It's illegal for a shop to cut out cats and replace them with straight pipes anyways. I live in Iowa where there's not even emissions laws or any of that jive that you california and other people have...Now I cut out my cats and took them down to some muffler shop full of rednecks one day and asked them to bend me up some pipes to replace them and they wouldn't even do that....even though I told them it was for an off road application. I'm pretty sure that if they (the shop) get caught then there are massive fines involved.

[badmonkey]

damn tree huggers . i dont see why people care so much, people don't realize how the emissions system works. You are penalized based on the county you live in. In TX houston has probably the 2nd most strict emissions testing besides Cali, but if your car is register just outside of harris county you can run anything you want. There are 80's POS chevy carburated trucks with no cats and etc putting out 10 times the polutants any non-catted M3 could every produce and they can do it legally. The system itself is very flawed so theres no point in trying be emissions friendly when there are cars legally putting out much much more than you are solely b/c they live outside the city limits, its just stupid.

Besides the US government has already figured out a cure to global warming which is why they aren't really doing a damn thing to bother stopping it. I did a 5 page research paper on the topic... heres the link.... read to your hearts content....

http://www.lanl.gov/news/releases/archive/02-028.shtml

The cure for global warming has already been withing reach for quite some time. in a decade our air quality will be even better than before the industrial revolution of hte 1870's. So pollutions is not a factor, polute to your hearts content. What we have to worry about is the fact that we only have 50 years of oil left based on the current oil reserves, so in the next 5 years there will be a big shift into alternative fuel sources (hence BMW's Hydrogen internal combustion chamber project: H2R). Sorry to reign on every tree huggers parade

Plug a Sun exhaust analyzer into the tailpipe of your car with cats and without.
Report back here with the results.



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[Darth Maul]

I had my shop do it and it's worth it, I feel my car's faster and the sound is louder around 3K+. I think it was worth it and way cheaper than buying a track pipe. Just Do It.

[Zeke]

I had my shop do it and it's worth it, I feel my car's faster and the sound is louder around 3K+. I think it was worth it and way cheaper than buying a track pipe. Just Do It.

how much did you pay? Did you have the cats cut out or the resonators (or are there even resonators?

[Darth Maul]

yeah, their are resonators there. It cost me $100, by one of my friends shops.

[GotBHP?]

do you think being penalized for something just b/c of where you live is right either? it depends on your perspective on things

True, this isnt perfect, but from your perspective can you honestly say that running no cats is an ok thing to do? Take a look at the junk that will be coming out of your tailpipe...how is that worth 5hp (and it really is around or less than 5 hp, despite what people's butt dynos feel ). Do you street race so often that the 5hp is going to help inflate your ego that much? I mean, come on...

That being said I'm no huge tree-hugger, but keep in mind its a *street* car.

[Chris Huff]

I had my shop do it and it's worth it, I feel my car's faster and the sound is louder around 3K+. I think it was worth it and way cheaper than buying a track pipe. Just Do It.

I may have missed this, but did you leave the resonators in and just cut the cats out?

I want to do this to my car, but want to avoid the raspyness and keep the tone down a little. Still running the stock muffler for now.

[VRRHEUM]

damn tree huggers . i dont see why people care so much, people don't realize how the emissions system works. You are penalized based on the county you live in. In TX houston has probably the 2nd most strict emissions testing besides Cali, but if your car is register just outside of harris county you can run anything you want. There are 80's POS chevy carburated trucks with no cats and etc putting out 10 times the polutants any non-catted M3 could every produce and they can do it legally. The system itself is very flawed so theres no point in trying be emissions friendly when there are cars legally putting out much much more than you are solely b/c they live outside the city limits, its just stupid.

Besides the US government has already figured out a cure to global warming which is why they aren't really doing a damn thing to bother stopping it. I did a 5 page research paper on the topic... heres the link.... read to your hearts content....

http://www.lanl.gov/news/releases/archive/02-028.shtml

The cure for global warming has already been withing reach for quite some time. in a decade our air quality will be even better than before the industrial revolution of hte 1870's. So pollutions is not a factor, polute to your hearts content. What we have to worry about is the fact that we only have 50 years of oil left based on the current oil reserves, so in the next 5 years there will be a big shift into alternative fuel sources (hence BMW's Hydrogen internal combustion chamber project: H2R). Sorry to reign on every tree huggers parade

The first rule of the forums is respect. That being said. With all due respect, you are retarded.

-Scott

[SG_M3]

you are retarded.

agreed.

[WCM3]

I'm thinking of doing the same thing. However, I'm also installing a rms stage II supercharger setup. I'm looking for a more burblier exhaust tone. Would just cutting the cats out and keeping the resonators get me that. I have a Remus catback...Thanks
-Mike

[ZimDoc]

I had my shop do it and it's worth it, I feel my car's faster and the sound is louder around 3K+. I think it was worth it and way cheaper than buying a track pipe. Just Do It.

This isn't always true. Most peoples minds think if its louder, its always faster.

So the best way to test it is a dyno.

[beatniks325]

i just read this on cnn and i thought it was relavant to this thread:
http://www.cnn.com/2005/TECH/03/15/s....ap/index.html

Bush awarded catalytic converter inventors (from left to right) Ronald M. Lewis, Irwin Lachman, and Rodney D. Bagley with the National Medal of Technology.

[BTSG325i]

Question about the OBDI setup, I just want to make sure that the first of the two sections is the resonator, and the second is the catalytic converter. Is this correct, or are they both cats? Because I've got a massive rust hole in one of cats, and I'm just planning on taking them out and leaving the original resonators up there, and welding in about a foot of piping on each resonator.

[Bernanke]

well my isn't really a street car anymore, infact in the summer im gonna take it out of commission. its pretty much gonna be for track use only from now on, its too nice to drive on a daily basis, im worried something will happen to it (accident and etc or even worse). I'm not necessarily advocating it, but i think it is worth the gains it provides, hell i'd do it for the sound alone. its obviously not as good as running cats but there are many cars out there poluting alot more than a non-catted 3.0L M3. majority of polution does not even come from the automobiles it comes from those unregulated factories and plants pumping out god knows what into the air and they are getting away with it due to loopholes in the system and etc b/c of the pollution points system and they basically just pay off the government to pump whatever they want, if anyone should be penalized its the factories and plants, passing the blame onto the consumer is hardly the best way to solve the problem, but then again every system has its faults.

Again its up to the user to deside, personally i could care less b/c there are far many more cars out there that need attention to first. If you want to keep your cats on then so be it, the only car this really applies to anyways is the 1995 E36 US spec M3, anyone else should not even be bothering with this conversation b/c it pretty much doesnt apply to you. OBD2 its not worth it at all, and regular E36 it really won't make much of a difference if any at all. again it is an off road application, I wanted it b/c i wanted full AA exhaust system from headers to the tips (no different than full SS setup and i dont see peope pointing fingers at that setup, everyone always talks about track pipe, no one talks about SS system), that was always my goal so thats what i did.

To each his own, either way in a few decades or so this topic will be irrelevant b/c by then the industry will have converted over to alternative fuels and etc, and we'll all be driving flying cars to work .