6.9 exhaust design

[WGB]

Great stuff - really magnificent.

I hope it is easy to drop out without damage if you need to service the driveline or oil seals (Just kidding).

Bill

[s class]

Trust me Bill, I gave that a lot of consideration - I did post a pic of the flange joints before the rear silencer.  We were considering another set of jounts in the vicinity of the rear end of the gearbox, bu eventually opted against it on the grounds of clearance issues. 

[CraigS]

Thanks TJ - the pictures don't do it justices.  Its a masterpiece actually.  As any 6.9 owner knows, on the driver's side, the space to get the downpipe through is very tight between the steering box, bellhousing and cross-member.  Its tough even with the standard 50mm pipe.  These guys got 57mm through there, and there is no touching or rattling. 

As long as the engine/transmission mounts are in good condition, there should not be a problem. The problem would arise if any of these were badly worn.

[Tom R.]

Is there a soundfile of this exhaust?

[Niclas]

Great work S-class!
Have you noticed any gain in performance?

Do you have a calculation program of your own or can you find it on the internet somwhere?

/Niclas

[s class]

Exhaust manifold design is a complex area that I've spent time on at a few points in the last number of years.  There are no clear standard formulae that can be used.  There are a number of issues that must be taken into account.

In this case, I was constrained by existing manifold dimensions, and the location of the silencers.  The choice of pipe diameter was debatable.  The 57mm was slightly on the large side, favouring high speed performance at the expense of a little bottom end torque.  If you want the opposite compromise, go one size smaller.

Sorry there is no sound file at the moment.  I must look into creating one though. 

[motec6.9]

Hi S Class i dont know about power increases from exhaust alone but i will post dyno report from my car once tunning is finished it has the exaust that is pictured in another post on here with extractors fitted as well aslo fitted with motec efi computer

[SELfor50]

Looks great Ryan!!  Very tidy job.  Love the straight tips, got that nice raw touch to it. 

Keen to hear an audio recording of it.