Hi, finally, after months of suffering (because the stupid customs down here) I got my eisenman race cat back from Germany today.
So, id like to make my own mid section, does anyone have a pic of their aftermarket exhaust ? is it better to have 2 straight tubes from the headers to the muffler than having an x pipe somewhere there ? I was told that the 3.2 has an X pipe so the cats can warm up faster.... my 3.0 does NOT have an X pipe.... so what would be the best thing to do ?

Thanks

No one knows for sure. However, I have both versions of the midpipes that Supersprint offered (x-pipe and no x-pipe) and I plan to do a dyno comparison...eventually.

FYI, Supersprint only offers the version with the x-pipe. You're better off just buying that...it's a quality piece.

got mine made up at local exhaust place for ~ $120
http://i5.photobucket.com/albums/y171/morerevsm3/Picture410.jpg

No one knows for sure. However, I have both versions of the midpipes that Supersprint offered (x-pipe and no x-pipe) and I plan to do a dyno comparison...eventually.

FYI, Supersprint only offers the version with the x-pipe. You're better off just buying that...it's a quality piece.

Please do it, id be awesome to see that dynochart.

got mine made up at local exhaust place for ~ $120
http://i5.photobucket.com/albums/y171/morerevsm3/Picture410.jpg

It looks great Alan, I see that the X comes after your resonators (you dont have cats right?), whats the main purpose of the X, to even the pressure maybe ? Did you feel gains after installing it ?

well, here it is....... Eisenman Race catback.... just arrived

http://img529.imageshack.us/img529/4508/img00381me1.jpg

http://img106.imageshack.us/img106/3416/img00382rs7.jpg

http://img106.imageshack.us/img106/165/img00383hz3.jpg

Here is mine - BMW Motorsport GrpA system.

http://www.indexofimages.com/uploads/ae68b356ac.jpg

i always hear that BMW engine's like to run with the X-pipe .. my friend removed his and it lost quite a bit of torque and sounded shitty .. so he reinstalled.

ps: that GrpA exhaust system is HOT!!!!

So.. what is GrpA and GrpN?

Awesome, whats the width on those pipes ?

They are about 72mm each! (2.75 inches)

GrpA and GrpN are class-specific racing components made in house by BMW.

It looks great Alan, I see that the X comes after your resonators (you dont have cats right?), whats the main purpose of the X, to even the pressure maybe ? Did you feel gains after installing it ?
they are high flow metal cats, X pipe replaced the resonator

I was about to purchase the supersprint midpipe...but wasnt sure to go w/ the race or performance one

I was about to purchase the supersprint midpipe...but wasnt sure to go w/ the race or performance one

Performance one - it has the Xpipe and resonators. The Race is simply (overpriced) straight pipes.

that's insane Vitolo... dual 72mm !!!

im running the S50B32 with stock E30 m3 dual system, they are like 42mm each...

how does the euro S50 run with bigger systems ?
and does anybody know the stock system diameter ?

that's insane Vitolo... dual 72mm !!!

im running the S50B32 with stock E30 m3 dual system, they are like 42mm each...

how does the euro S50 run with bigger systems ?
and does anybody know the stock system diameter ?

Haha yeah, they are HUGE! Pics did not do them justice when they arrived. :eek: The piping on my dad's E55 isn't even as big :laugh

42mm?? You are choking that motor man! Open it up!!

I know the US M3 piping is 2.25 inch and the stock Euro stuff was visibly larger in comparison. If memory serves me correct, I beleive stock Euro S50 exhaust piping is 2.5 inches, or roughly 60mm? Not 100% sure on that one.

Have not run the car yet with this system... I was wary of it's size and the possible loss of low end torque, but it has a very nice X pipe up front and 2-stage high flow cats so hopefully it has *enough* backpressure to be decent. If not then I will upgrade the 3:46 rear end to a 3:64 to help out.

I've heard the GrpA exhaust for the E30 M3 was supposed to be the best gain in performance without loss of power so maybe they had the same goals in mind when designing this E36 system...?

Stock Euro is twin 2.5" or 64mm. Twin 42s would be like a noose around its throat, let it breathe!

the x-pipe is a winner on the 3.2. i put my merge just after the cats and picked up 8rwkw. it helps with the exhaust scavenging. IMO is mandatory performance modification

But wait, so whats the real purpose of the "X" then ? :confused

Even the pressure ?
Warm up the cats faster ?
Scavenge ?
Venturi effect ?

Have you guys ever seen this "CCInserts" things from www.carchemistry.com ?

http://www.carchemistry.com/shop/images/products/products_inserts_3DI25R_tn.gif

anyone used them instead of resonators ?

Performance one - it has the Xpipe and resonators. The Race is simply (overpriced) straight pipes....but the race straight pipes are WAY lighter and fully stainless.

exhaust piping is 2.5 inches, or roughly 60mm?You're right.

...but the race straight pipes are WAY lighter and fully stainless.

True, but they use much thinner walled tubing to accomplish that.... which aside from increased noise/rasp, they will not hold up *as well* over time to the elements.

Still confused about how the X-Pipe makes better power. I have been told about it so many times that it is good.

aha, i measured the pipe from the 3-1 header and it was ~50mm, so i thought stock was dual 50mm, but 62mm vs 42mm is a huge difference!

So if i plan to eventually swap in an s50b32 would adding a custom xpipe to my m52 be of any benefit?

Also has anyone put an e46 m3 midsection in their e36?
I have seen it done but do not know if made power or whatnot...

Why do you not post sound clips, Vitolo?

i think he stated his car is not yet running...:(

So if i plan to eventually swap in an s50b32 would adding a custom xpipe to my m52 be of any benefit?

Also has anyone put an e46 m3 midsection in their e36?
I have seen it done but do not know if made power or whatnot...

no, because entire exhaust will need to be raplaced with 2.5" system

Still confused about how the X-Pipe makes better power. I have been told about it so many times that it is good.

If BMW Motorsport put an X-pipe on their $$$$ Group A exhaust (see Vitolo's post), I would highly assume that's the way to go performance wise. I just don't see german engineers doing it for looks :D

well maybe on farfus cars!! (see this week end wtcc action in Pau)

Seriously, would there be any gains or differences between H-pipe and X-pipe? I would think X-pipe allow for more continuous flow and less turbulences.

taken from MagnaFlow performance:

"The reason an X-Pipe crossover works better than an H-pipe crossover isn't more flow because of volume, but more effective use of exhaust gas velocity. Exhaust gas (or air) has surface tension, and flows much like liquid would through the same pipe system. As the cylinders of each bank on a "V" style motor fire, they create a pulse in the system. The pulses will alternate back and forth from bank to bank as the motor runs. With multiple cylinders, such as a V-8, the eight cylinders alternately fire creates lots of pulses in the system.
If you put your hand behind the tailpipe, it would feel like a constant flow of air, but what it really is a lot of singular pulses giving the impression of constant flow. The idea behind the H and X style crossover is to unite the two banks of cylinders for better exhaust gas scavenging. Instead of two separate banks of four cylinders doing their own work, the crossover uses the pulse created by a firing cylinder of one bank to create a vacuum in the other bank because of surface tension. When a cylinder of the other bank is ready to fire, instead of the piston having to force the exhaust gas out of the cylinder, the vacuum that was created by the other cylinder bank helps suck the exhaust gas out of the cylinder, hence the term "scavenging."
Whenever you can reduce the load on an internal combustion engine, you are likely going to see performance and efficiency benefits. The difference between an H and X crossover is a smoother path for the exhaust gas to follow. Exhaust gas, like a liquid, will follow a path with the least amount of resistance. An H crossover has a path with two sharp 90-degree angles that are close together. An X crossover has a path with a much more gradual bend to allow the exhaust gases to continue their path back out to the ends of the tailpipes, rather then turning sideways for a short distance, then turn again to head out the tailpipes. Smooth flow with high velocity means more power by use of scavenging. Using an exhaust system with too large of piping diameter work against scavenging in the same way that running an exhaust with too small of tubing chokes the motor and forces it to work harder to expel the exhaust gases. "

for the lazy guys: summary is that X/H pipes give better performance & X pipes are better than the H pipes.

HTH,
eric

Awesome, just the explanation I needed, thanks

Yup, that explains it...now for the more complicated question...

Does it matter how far away from the engine block the X happens? I know in exhaust systems, the length of each component is key also...like in a header, they should all be approx the same length etc etc. Or maybe it does not matter.

well i read somewhere that you want the X-pipe to be as close as possible to the rearend of the car .. have no idea why though.. no time to search atm.. damn finals :(

But the GrpA system on Vitolo's car, has it right next to the transmission, at the beginning of the system...

found this:
"Fitting a crossover pipe up closer to the exhaust valves can hurt performance by allowing high pressure gas pulses to reach the open exhaust valves on the other side of the engine. It also reduces the length of the pipe that produces inertia scavaging."

i read something similar earlier on another website.. so apparently theoretically, the closer to the rearend of the car the better for performance... keep in mind there might be a million reasons why the GrpA system is like that.. like to avoid cabin resonances or i dont know what else!

just talked to a friend (big bmw enthusiast)

Mr. K says:
there is an old-school way of knowing the best place to put an x-pipe
Mr. K says:
you paint a white line with a brush after the headers primaries, and run the engine full blast for a bit
Mr. K says:
see where the paint burns, and THAT is the perfect spot for the x-pipe, because that's the point of highest pressure

just talked to a friend (big bmw enthusiast)

Mr. K says:
there is an old-school way of knowing the best place to put an x-pipe
Mr. K says:
you paint a white line with a brush after the headers primaries, and run the engine full blast for a bit
Mr. K says:
see where the paint burns, and THAT is the perfect spot for the x-pipe, because that's the point of highest pressure



Great info!

just talked to a friend (big bmw enthusiast)

Mr. K says:
there is an old-school way of knowing the best place to put an x-pipe
Mr. K says:
you paint a white line with a brush after the headers primaries, and run the engine full blast for a bit
Mr. K says:
see where the paint burns, and THAT is the perfect spot for the x-pipe, because that's the point of highest pressure
The location of the x-pipe is in different locations on the Gp A exhaust and Supersprint mid-pipe. I wonder why that is?

The location of the x-pipe is in different locations on the Gp A exhaust and Supersprint mid-pipe. I wonder why that is?

Yeah, the Supersprint I think is closer to the rear of the car...

just talked to a friend (big bmw enthusiast)

Mr. K says:
there is an old-school way of knowing the best place to put an x-pipe
Mr. K says:
you paint a white line with a brush after the headers primaries, and run the engine full blast for a bit
Mr. K says:
see where the paint burns, and THAT is the perfect spot for the x-pipe, because that's the point of highest pressure


wow, that is old school...but really cool! haha!

good stuff allt that, just need to get white paint then!

i wouldnt be putting it towards the rear. id be more inclined to have it straight after the cats

instead of the cats you mean?? :lol

no we have to keep our cats

Yeah, the Supersprint I think is closer to the rear of the car...

The Supersprint is where the OE cats would begin, under the transmission. Mine as posted earlier, is placed under the passenger(LHD) footwell.

ok, heres what I got from the supersprint website...

043602
Front exhaust with Metal Kat. R.+ L.
This one comes with what I believe are, high flow cats.... It has the X" before the cats, right after the O2 sensors....(just like on Vitolos GrpA midpipe)

http://www.supersprint.com/prodotti/043602.jpg

784302
Front exhaust Replaces Kat.
This other one, has NO CATS, but two resonators, but no X pipe....
http://www.supersprint.com/prodotti/784302.jpg

ok, heres what I got from the supersprint website...

043602
Front exhaust with Metal Kat. R.+ L.
This one comes with what I believe are, high flow cats.... It has the X" before the cats, right after the O2 sensors....(just like on Vitolos GrpA midpipe)

http://www.supersprint.com/prodotti/043602.jpg

784302
Front exhaust Replaces Kat.
This other one, has NO CATS, but two resonators, but no X pipe....
http://www.supersprint.com/prodotti/784302.jpg

My X-pipe is even closer to the headers than the Supersprints, look close at my pic and you'll see its right after the header BEFORE the 's' bend.

The 043602 metal kat system costs about $1800USD last I checked. Pricey but good cat's are worth it, and it's not SO bad when compared to buying new OE replacement cat's which are about $1300 IIRC.

Supersprint made versions both with and without the X-pipe. I tried but was never able to confirm... a few members on this board as well as e36coupe.uk have gotten them recently and they got the one with the X-pipe without specifying for it. I beleive it is the updated version so that pic of the resonator without it is probably the old model that was replaced/outdated.

I beleive it is the updated version so that pic of the resonator without it is probably the old model that was replaced/outdated.Correct.

I had the Supersprint "decat" pipe with crossover and resonators on my 3.0L but didnt notice much difference other the smell of rich fumes

now I have to replace the CAT

does anyone have the Supersprint CAT ?

how does it perform on emissions test ?


Benji ... I regret not hooking up in Van ... I'm in Ontario now after starting new job ... Craig

Benji ... I regret not hooking up in Van ... I'm in Ontario now after starting new job ... Craig:(

Did you leave #20 behind? :devillook

#20 is with me
hoping to get together with #1 soon
having trouble getting the emissions test done in order to change the plates
i think my CAT is done for :(

having trouble getting the emissions test done in order to change the plates
i think my CAT is done for :(How many miles on #20? What exactly is the emissions problem you're having?

BTW - I spoke with Chris@CG a few days ago and he told me that of all the eurospecs he's driven, yours was the strongest.

He hasn't driven #19, though. :evil2 :stickoutt

the CO & HO levels are good
the NOx level is a little high (750 ppm where limit is 435 ppm)

I still speak to Chris & Rudi
not sure what to do now though

the CO & HO levels are good
the NOx level is a little high (750 ppm where limit is 435 ppm)

I still speak to Chris & Rudi
not sure what to do now thoughHow many kms on your ride? I just want to get an idea how much longer my cats will last.

207000 km now
the thing is it passed Air Care last Sept
now 6 months later it doesnt

I think there is some kind of air pump pushing air from the airbox to the exhaust, if this is the case and it's not working fixing will bring your readings to a lower level

I think there is some kind of air pump pushing air from the airbox to the exhaust, if this is the case and it's not working fixing will bring your readings to a lower level
the air pump only operates for a minute or so, it is for cold start emissions only

then can you just force start her for the emission test?? :D

Here is mine - BMW Motorsport GrpA system.

http://www.indexofimages.com/uploads/ae68b356ac.jpg

Where did you pickup that system? Was that one of the systems that Turner had for sale a while back? What was the cost?

hey JV, are those pipe clamps securing the exaust pipes to the cats? That is stainless right? The welds look very similar to that of Ti. Nice brakes btw.

I demand more underbody pics.

hey JV, are those pipe clamps securing the exaust pipes to the cats? That is stainless right? The welds look very similar to that of Ti. Nice brakes btw.

I demand more underbody pics.

lol, ok... this is the only other one I have
http://www.indexofimages.com/uploads/0b2a12441a.jpg

They are v-band clamps. Entire thing is stainless/tig welded.

lol, ok... this is the only other one I have
http://www.indexofimages.com/uploads/0b2a12441a.jpg

They are v-band clamps. Entire thing is stainless/tig welded.

I want I want. Now just how much. Also in south africa we dont need the cats.

I want I want. Now just how much. Also in south africa we dont need the cats.

It will cost you about $10,000 USD to get another one of these. They are handmade in Germany by BMW Motorsport GmBH

It will cost you about $10,000 USD to get another one of these. They are handmade in Germany by BMW Motorsport GmBH

Well aren't you special? ;-)

Well aren't you special? ;-)

Yup! :D

http://images.jupiterimages.com/common/detail/82/38/23303882.jpg

:lol

hey jon, your missing a few spring clips on the tail section. I believe thats what those brackets are for.

It will cost you about $10,000 USD to get another one of these. They are handmade in Germany by BMW Motorsport GmBH

I dont want one anymore. :(

hey jon, your missing a few spring clips on the tail section. I believe thats what those brackets are for.

Yea I know. I put some on, those pics were from when I first installed the whole thing.

I just bought a tig. I think Ill make the exaust this weekend...