What’s the difference between the two exhausts? I mostly drive on street but go ti track several times a year.

Need something that I can live with on trips but give me some hp gains on my 2007 MCS.

Also getting a cold air i take. Maybe DDMWORKS Street.

 

No second cat, larger resonator, and
different muffler on the factory JCW R56
MCS exhaust.
The JCW tuning kit exhaust just has the
different muffler.

 

The LCI R56/55 JCW exhaust has a second cat and smaller resonator. The early cars had the larger resonator with no second cat.

Best I can tell, the LCI JCW exhaust only has different tips... The internal baffling on the muffler might be slightly different, but I don't imagine it makes much difference in power.

 

Mostly sound is the difference and tips. Maybe a little less restricted on the JCW but its marginal. I have it and it sounds good.

 

As I remember, one of the initial claims was that the factory JCW exhaust was a somewhat larger diameter...

 

Picked up an early jcw exhaust. It has the larger resonator but the tips aren’t engraved. Its the same size as my original. It does sound different just off throttle and at 4-5k rpm. Sounds good though. Might have more power but only one drive on it so far.

On first drive I smelled rotten eggs after high speeds but the exhaust was sitting for a number of years. Might go away.

 

OK, new question. I installed the early style JCW exhaust onto my R56 S. I still smell some rotten egg smell in the cabin with windows up after decal from high rpms.
Is this normal for JCWs? I don't see a gasket between the downpipe and exhaust flange. I see the downpipes are different part numbers, is there a difference in them since JCWs don't have the second cat?
What do you recommend to get rid of the smell?

 

There should be a gasket between the down pipe and the exhaust pipe. If there isn’t, it could be leaking. Do you have a cat less down pipe, or it still OEM?

 

I have the OEM downpipe. When I looked up the exhaust on Realoem it doesn’t show a gasket. Do you have a part number or link to one?

 

I don’t know if you can purchase just the gasket, but it come with a new clamp:
https://www.ecstuning.com/b-hjs-part...302756352~hjs/

 

Just the clamp/gasket you can get.

 

i have that clamp gasket on the down pipe side. Nothing on the exhaust side.

Is that correct?

 

Just that clamp on the connection from the DP to the cat back. On the upper part of the DP to the turbo there is a gasket. If you have an aftermarket exhaust they will have sometimes a band clamp half way back or select OEM exhaust.

 

It will only install correctly one way. If you re-used the old clamp, you might not have transferred the gasket.

 

The gasket (metal) is still attached to the down pipe.

 

I am installing a new clamp, and it came with the gasket which has a bunch of tabs around the outside edge. What's the proper way to install this gasket and the clamp?

Do all of the tabs go on the outside of the flange from the catalytic converter? Or do some go outside and some inside? Is the purpose of those tabs just to hold it in place while installing the clamp?

I removed the old clamp and gasket because it was leaking exhaust pretty badly there. the pipes are all in fine shape. The old gasket was still intact, but most of the tabs were broken off, and they were just mashed inside the joint. Any advice?





Thanks!

 

They go together. Little bit of a pain. Sets like the one below. Then connects to the front of the pipe. Clamps like the old ones in the same orientation.

https://www.ecstuning.com/Search/Sit...h/18302756352/

 

JCW plus catless Downpipe and RPM tune. Way to go. I promise I get in my F80 M3 and I'm very disappointed relative to the R56...acknowledging the F80 stock exhaust is a bit boring.