Hmm, can't see that in the pic .. Looks like it just goes straight into the steel wall and somehow merges into the main pipe ..

Seems very very restrictive as soon as it comes out the back of the Turbo? I'll have a look at my old standard dump when i get home and see how that works.

I figure that when the WG opens, you want that gas to free flow out, into a seperate pipe the join up short time afterwards.

Good on ya for having a crack Al. I took one of the so called best dump pipes for the Evo and had further mods done to it. As you have suggested, getting an exh housing is the key. Maybe do some ceramic coating while you are at it...

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Ducati 998s
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The MSR dumps have a very short splitter which basically merges straight into the main flow.
Yes I was going to give it a bit of a port job while I was at it Stace....
Just wanted to make sure I knew wtf I was doing
BP, what did you do to your dump?

Yeah the MSR dumps work on the principle of having a large volume to allow the exhaust gases to expand. Very similar to what Prodrive used on their old Group A cars. The small splitter just stops the gases from WG going straight in to the main exhaust flow causing turbulence.

I'm currently using an MSR twin scroll dump without splitter and it seems to work well.

The Evo one was an open mouth design. Got an exhaust housing and I had a splitter welded into it and ceramic coated it. Was always a fan of the splitter design on the WRX so thought the Evo would also benefit. Nothing to compare to though to verify any results. But guys have tested them in the US with encouraging results.

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Rotor of Fail
Ducati 998s
Ducati Streetfighter S
496 CI Injected Big Block. Carbon positive???

Having a flat splitter avoids creating a pressure differential making it easier to control boost. I have seen "RMS Dump Pipes" vary subject to the customers budget.
The pictured dump pipe is very similar to the Perth Exhaust Centre item with its small waste gate collector + splitter. Better than OEM but not in the same league as MSR imho.

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Here's what I did with my new Xforce bell mouth dump.

Added a 22mm splitter to suit the TD04, done a bit of die grinding then had it HPC coated along with the heat shield.

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Yeah go with the MSR if you want it rubbing on your steering coupling. That way you can really feel the dump pipe work. Had this problem myself and seen a few others.

Same here. Had slight clearance issues, nothing a tap with a hammer didn't fix.

I see this was just linked so thought I had better update it.
I removed the piece of tube from the dump, ported the clappers out of it and welded a new splitter in (2mm flat bar across the mouth) to finish it off. HAving said all that Leigh recomends they are fine as is for big HP ie Brads beast has one I think?
Al