Custom M3 Dual exhaust, Opinions?

[Bernanke]

...

[comptechgsr]

why not eliminate the x-pipe and have a "tru" dual exhaust

[rfc2307]

I have been looking to get this done but haven't had the time. If you do have it done, please post a parts list, etc... I have had very good luck with the 3" Stainless Steel tubing from J.C. Whitney (go figure) I have used it in a few intake projects to date, it is easier to weld to for some reason.

Good Luck, definetly keep us posted.

rfc2307@hotmail.com

[clumpymold]

Yeah, I'm somewhat interested in this as well. Do you have to modify your rear bumper to accomodate the exhaust?

What about the underside? How do you get it to fit?

[mbanks21]

Only thing Im concerned about it having enough backpressure. It might look and sound sweet but if I lose HP and torque- uh uh

[Max M3]

The purpose of the X-pipe is to increase both high end HP and low end torque. If the two pipes did not connect at all you would not be getting full potential power out of the exhaust system.

Sorry, you can't have it both ways... You either get better breathing at higher rpm's or better low end torque... not both. There's no point to that "X" design that I can see.

[mbanks21]

Wouldnt the X be better closer towards the headers anyway? Im thinking there wont be enough backpressure unless you have some kind of muffler system

[clumpymold]

Well, pretty much ANY aftermarket exhaust is going to relieve a bit of backpressure so you'll lose a tad on low end torque but gain it up high.

That X design only works, IMO, if it's NOT Mandrel bent. That way it may help a bit. If you really want to make it similar in low end torque to a single exit, dual pipe exhaust, measure the total area of each of the pipes. Assuming a 3" tip and piping, you're looking at a total of 3.14159(1.5)^2 x 2. As long as the TOTAL area of all the four pipes is equal to that value, you're good to go. You can actually keep the tips 3" on all four tips and just get smaller pipes that equal the total area of the original two.

[mbanks21]

So you wouldnt even need mufflers if you had enough resonators?

[dave is cool]

SupaBimma, how much would it cost to have that custom exhaust made, including all the parts, installation, etc.?

[clumpymold]

So you wouldnt even need mufflers if you had enough resonators?

I don't think you really need mufflers in general. They're only there to help minimize noise. On my last car (Audi) it came stock with TWO mufflers. I removed one of them and the sound was awesome. Talk about cheap upgrade.

So if you want it loud, don't have the mufflers. I would put them on though.

[mbanks21]

I have a vert so I dont want too loud. I paid less than $200 for 2 Magnaflow stainless steel mufflers and a variety of mandrel bent "U" and "J" pieces and a few feet of stainless steel tubing.

[Rich V]

I don't think you will have room for a muffler on the right rear area without loosing ground clearance, not to mention the fact it would hang low and look really silly...

[mbanks21]

Ive already planned this out AND purchased all the necessary parts. Were going to move the battery and cut away a spot for the passenger side muffler to tuck up into. I plan on using a Supersprint Euro resonator and 2 Magnaflow mufflers.

[comptechgsr]

[IMG]http://forums.**********************************.php?atta chmentid=66326&stc=1[/IMG]

hey, that's what i said. 2nd post =)

lol

with this design you will probably gain more HP up top, but lose torque down low.

i really dont know how an x-pipe would increase both hp up high and torque down low, unless it came with nawss

good luck and show us pics!

[Rob Levinson]

For those of you concerned about torque loss with a free-flow exhaust... have you converted your M3 to a Solex 1-barrel carburetor?

The myth revealed:

http://www.uucmotorwerks.com/html_pr...torquemyth.htm

Before someone responds with "I installed a free-flow exhaust on my M3 and lost torque", ask yourself this: are you sure you're not being tricked by how much more high-end power you have making the less-enhanced low end power feel diminished in comparison only? The concept has been discussed extensively on this and other message boards, but I guess the internet has a short memory.

As for a dual exhaust on the E36 M3, you've got one major problem - battery box in the trunk is in the way. When some of the European tuners used to offer this kind of exhaust, it required extensive "surgery" to cut out the floor of the trunk, not to mention needing a new (or modified) rear valance.

There would be no gain from a "wide dual" exhaust over a standard E36 "standard dual" performance exhaust. Even the E46 M3's "wide dual" is just a bizarrely shaped muffler so that "quad tips" could be seen and look cool... at the cost of a lot of additional weight.

[slickwill21]

How about Eisenmann, They make one for the M3!!

http://www.eisenhaus.com/ehprice.php

[slickwill21]

sorry try this link!
http://www.eisenhaus.com/images/subm...d/e36_4x70.jpg

the bad part is it is $1,450

[Max M3]

H-pipe is more for high end power,
but X-pipe makes less high end HP in order to make more low end torque.

You just contradicted yourself.
Physics teaches us : It's not possible to just change the exhaust path and get more high end AND more low end.

[clumpymold]

sorry try this link!
http://www.eisenhaus.com/images/subm...d/e36_4x70.jpg

the bad part is it is $1,450

OMG that's crazy. Why would anyone pay that much for a fake dual exhaust? Just have someone make it for like $200-300. Granted it won't be Mandrel bent but it shouldn't be that bad.

[JLC325i]

I think your idea is trash, but I think all of your ideas are trash so take it for what it's worth.

[SG_M3]

You just contradicted yourself.
Physics teaches us : It's not possible to just change the exhaust path and get more high end AND more low end.

Max is correct, you get one or the other. H's make low end power, while X's make higher rpm power.

[Hellrot332ti]

Why the hell would you want 4 resonators and 2 mufflers??? Thats just crazy. Ethier get only 2 resonators or the 2 mufflers. With just mufflers and cats the car will be quiet so the resonators are kinda over kill. If anything your first idea was best. Do the cats, 2 resonators (one on each pipe) and the 3 inch tips with no mufflers. Would sound awesome.

[Dirty Phil]

i was planning on getting a custom exhaust as well. dual exhaust with quad 3" tips. I was planning on just making it simple:

Y-Pipe connecting the single muffler to the quad tips, with no resonator.
2.5-3.0" piping to allow more air flow
high flow cats

[Bernanke]

First off that eisenman is hte ugliest most retarted exhaust system on the face of the planet.

second off I'm not worried about back pressure becuase I will get betting Eurosport twin screw thats not an issue either.

There is limited space under the passenger side but I will make some measurements to see just how much there is, if there is more than 5 inches then one of those universal exhausts will fit.

You are right, if i run two mufflers then i will only probably run two long magnaflow XL resonators.

My bad on X-pipe, i always mix them up. either way its better than just two straight pipes.

Thanks for opinions guys, keep them coming.