Does anyone have direct knowledge of the 3 types of exhaust manifolds available for the S and JCW? Not just info from say JMTC of WMW.
I hear the 3rd gen (N18??) is the best?? More free flowing, shorter and lighter. I'm getting conflicting info and would appreciate info that's not hearsay.

 

Hardly anyone has compared the only ext.manifold in dynorun? What kind of rumors you've heard? I run ported 3rd gen.(N18) ext.manifold with JMTC S42hp in MCS -07, no problems..

 

I was lead to believe that there were 3 different exhaust manifolds.

1st generation (round style) - N14 S - part# ??
2nd generation (square style) - N14 JCW and N18 JCW Tuning Kit - part# 7593149
3rd generation (round style) - N18 S, JCW and GP2 - part# 7597031

Now www.realoem.com list part# 7597031 as the exhaust manifold for N14 and N18 engines (S, JCW, GP2) and part# 7593149 and the exhaust manifold for N14 JCW and the N14/N18 JCW Tuning Kit.

Something confusing happened earlier today on Facebook. An owner of a GP2 posted a pick of what he claims to be the stock exhaust manifold and it was the square style with part#7593149 stamped on it. I don't think this is correct. I'm not sure if he is the original owner or if a previous owner had swapped out the manifold. I thought that I have seen pictures of MarioKart's GP2 exhaust manifold and it was the round style. Maybe Mario will chime in.

I know definitely that I have the round style part#7597031 on my 2013 N18 S

 

At my current state of tune (JCW turbo with 360 bearing and billet inlet wheel)we are not convinced that the manifold is an issue with the power. We feel the limitation is the size of the standard and JCW turbine exhaust housing and turbine wheel which is creating back pressure and reducing the increased bhp per PSI any higher than my current 265-270bhp.

Maybe once you step up to a turbo that is bigger than standard, then the exhaust manifold might be a restriction, however at the point any bigger non standard exhaust housing in your bigger turbo probably needs you to make a tubular manifold and this issue no longer exists (but you get the cracking exhaust manifold issue instead :-) ).

I guess I am saying that I'd only chase manifolds once you are going beyond my current BHP. Which of course you may have! :-)


Regards,
Steven_RW

 

There was actually closer to 4 part numbers and Realoem comes up wrong with since some part numbers ended or superseded to different part number. They latest JCW manifold has square long runners and uses better casting methods for much smoother "as-cast" appearance.

Out of the box the JCW manifold is the best hands down, you can tell by looking at the photos of them on WMW website that MINI engineers put some time and money into developing a JCW manifold.

The debate comes with the "ported" n18 manifolds. Sure its larger and 2 lbs heavier due to older casting methods used. It is also about $100 cheaper than a JCW manifold and I would think a little easier to get a hold of used if you are just going to port it and ceramic coat it for resell.

The only info I have seen about ported N18 manifold is about how the volume of each runner can be increased to be larger than JCW manifold. Volume and flow are not the same thing. So until flow numbers are produced we still like the JCW manifolds. Think of it like a ported cylinder head you can put the largest ports in the world on it but if your valves are still small it's gonna dictate how much of it is usable etc etc.

Here's a pic of 2013 JCW stock manifold and you can see the quality just in the external finish.

 

What turbo are you using that benefits from an improved manifold?

We found standard exhaust housing and turbine wheel (JCW spec) was the limiting factor, not the manifold.

Happy to hear I'm wrong and more power is available to me :-)

Thanks

Steven RW

 

That's a great question and hard one to answer. We tried to compare a n18 MCS with jcw turbo to N18 fJCW on the dyno and someone had a tank of cheap gas so we could not get a good reading on the N18 MCS with the JCW turbo. There again they do have slightly different compression ratios so it is still not a straight across compare.

 

Thanks for the straight forward reply .

We find that going to a much better tubular manifold just pushes the power up the power band and with most minis not revving more than 6500 to 7000rpm there didn't seem to be much benefit going for a higher rpm pOwer band.

Again it just depends what you want the car for .

Interesting stuff

Steven RW

 

I just got this JCW #7593149 for my N18 MCS is this a direct bolt on i running on stock turbo. Any improvement compare to the stock manifold?

 

Here is my N18 gen.3 ext.manifold , ported by JMTC.

 

 

Its funny you say that you can get the standard one easier. I tried parting with mine for almost 6 months and with no luck. I just ended up throwing it out.

 

Yep,I'm agree with you.I'm looking for a long time in different marketplaces,
but I found it NAM forums.It was sent from California to Arizona/JMTC to be ported and then sent to Finland , easy ....

 

To come back on the GP2 manifold: I have an European GP2 build 3-2013 an this had also the 2nd Gen Manifold 11627593149. Result after 25.000km a crack in the manifold. I just ordered the new 3th Gen manifold with article 11627597031.
So it seems the used old parts in the GP2... because when you check on BMW TK at the dealer on my car number there should be a 11627597031 installed... So they ****ed up in the factory.