RSR exhaust box

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Mike
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RSR exhaust box

Post by Mike »

I'd always wondered what was inside the twin outlet pipe RSR exhaust box, now I know......... absolutely **** all!

Image

Image

Image

That's all about to change, soon to be a switchable system, straight through, and then the centre section filled with all sorts of pipes,
flaps, levers and lagging, just to keep the boys with the decibel meters happy.

Also make it a bit more easy on the ear on the long motorway runs of course!
cheers, Mike.

previously..
1994 968 Club Sport Riviera Blue
1994 993 C2 Carrera Riviera Blue
1972 911S to Martini RSR Prototype Spec
1973 911E to RS Lightweight Specification
1981 924 Carrera GT ex Mexborough car
3.2 Carrera Sport x2
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hot66
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Post by hot66 »

sounds interesting ( no pun intended :roll: ) .
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Post by haasad »

What manufacturer was that box Mike ?

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Mike
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Post by Mike »

haasad wrote:What manufacturer was that box Mike ?
andy
Andy, it's the Dansk RSR box.
cheers, Mike.

previously..
1994 968 Club Sport Riviera Blue
1994 993 C2 Carrera Riviera Blue
1972 911S to Martini RSR Prototype Spec
1973 911E to RS Lightweight Specification
1981 924 Carrera GT ex Mexborough car
3.2 Carrera Sport x2
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Post by Alan @ CanfordClassics »

Hi Mike,

Great pics, that is so much simpler than when compared to an original set up.

Image

Alan
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911hillclimber
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Post by 911hillclimber »

Be fun welding the top back on as well...long way round to say the least.

What dB are you going for all silenced up?
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Post by Tosh »

Tack it in half a dozen spots

It's not as if sealing it will make a huge difference to the noise now is it? :lol:
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Post by haasad »

Mike, spill the beans what are you planning?

I fancy it might be an on the fly silent choice option for a stealthy approach 8)

andy
ddk member# 1527
Austin Healey 100/6, 1957 Fast Road ( now sold)
75 2.7 S backdated to "r" and very light (now sold).
Adria Camper
Buddy McCrae kneeboard.
Friar Tuck kneeboard.
Lots of Bicycles.
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Post by crisc204 »

Now 'they' sell those flaps with a solenoid like the ones a late 911 and boxsters all have although the late cars work alittle differently it does the same job.

So perhaps a pair of flaps on the button which when shut send the gases around the exhaust box rather than straight out.
am I warm yet...
Mike
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Post by Mike »

Neil's plan is to have flaps in the megaphone pipes that join the box to the headers with bypass pipes that route through the box and cross over.
The box is baffled and full of sound deadening material. The flaps will operate by cable which runs through to either the heater lever between the
seats or to the heater slider on the dash. You end up with a quiet system at the pull of a lever, specifically for the man with the decibel meter at
the track but then also to keep the neighbours happy on those early morning start ups and to stop the headaches on the long runs.

The downside is the cost, the expert exhaust fabricator who will build it is confident he can get it down to 100db but it will take a lot of time to
get right, and as always that's money!
cheers, Mike.

previously..
1994 968 Club Sport Riviera Blue
1994 993 C2 Carrera Riviera Blue
1972 911S to Martini RSR Prototype Spec
1973 911E to RS Lightweight Specification
1981 924 Carrera GT ex Mexborough car
3.2 Carrera Sport x2
Barry
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Post by Barry »

Nice idea Mike, and I can see there would be lots of applications for the principle, what with track days getting tighter and tighter.
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Post by Bruce M »

If it was me......

To package a re-routing into a silencer in the middle section but then return it to the original tailpipes would be very hard to package inside the original case. The turns to get the exhaust gas into the middle section and the 90 degree turn back into the original tailpipe would be very tight.

So.....

I'd suggest having butterfly flaps in each of the tailpipes (cable linked) and drilling more holes in the section inside the silencer. Then build a set of baffles that end up exiting the gas out of two new tailpipes (either in the centre or better yet next the originals). So from the rear it would look like a wild 4 outlet race exhaust but actually only the inner "quiet" pair would be working in stealth mode and if the butterflies were opened the straight-through flow would resume (with a very slight reduction in noise because of the extra drillings).
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Post by Barry »

I think Mike is looking for 100% factory look :wink: .
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Post by Bootsy »

Barry wrote:I think Mike is looking for 100% factory look :wink: .
Really? You'd never guess from his 'My new project' thread!

:wink:
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Post by Bruce M »

Ah, well that would make a difference... :lol:

Mind you it depends how accurate you want to be.

A slightly less obvious version, with a hidden extra tailpipe??

http://forums.pelicanparts.com/porsche- ... ffler.html

Although I'm guessing that one is nothing new to this crowd.
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