What a Transformation

Zitat

Flame suit on...........

Fire away guys

Alles anzeigen

Tony, your byline says "You came in that thing? Your braver than I thought".

Should that read "You came ON that thing?............."

Cheers

Zitat von anguswolfendale;52840

Gerry,
Do you think it would be possible to fabricate some sort of butterfly valve that would open a straight-through pipe in the rear silencer when the sports mode of the tiptronic box is activated? My thinking is that I like the "silent" cruise on the motorway and don't want a resonating exhaust to interfere with that, but if I want to get a bit serious and switch to sports, it would be great to reduce the exhaust back pressure and hear the true throaty roar of the V8. I always switch to sports suspension (I have the EDC) when I want to push it, so maybe a solenoid activating the butterfly could be switched by the S/K switch?

Oi! That was my idea I've been kicking that idea around in my head for a while, it would be a nice feature.

Zitat von Argonaut;52863

Oi! That was my idea I've been kicking that idea around in my head for a while, it would be a nice feature.

I would love it.

There is a precedent in the E65 7 series. There is a vacuum valve that switches the muffler inlet on an electrical signal--I think from the Sport switch but I am not really sure.

http://bmwfans.info/original/E…005/01/mg-18/ill-18_0485/

Zitat von TerryY;52903

There is a precedent in the E65 7 series. There is a vacuum valve that switches the muffler inlet on an electrical signal--I think from the Sport switch but I am not really sure.

http://bmwfans.info/original/E…005/01/mg-18/ill-18_0485/

Hmmm, got me thinking.... Maybe next year's project, I've already done too much (= spent too much) this year.

Zitat von anguswolfendale;52840

Gerry,
Do you think it would be possible to fabricate some sort of butterfly valve that would open a straight-through pipe in the rear silencer when the sports mode of the tiptronic box is activated? My thinking is that I like the "silent" cruise on the motorway and don't want a resonating exhaust to interfere with that, but if I want to get a bit serious and switch to sports, it would be great to reduce the exhaust back pressure and hear the true throaty roar of the V8. I always switch to sports suspension (I have the EDC) when I want to push it, so maybe a solenoid activating the butterfly could be switched by the S/K switch?

I just wrote a long reply to this and its dissappeared into cyberspace so as I cant be arsed to write it all again, here is the jist of it;

Yes, it is perfectly feasable to install an electrically operated, silencer bypass as in the Yamaha EXUP system, a tried and tested solution over 20 years old. However the cost of either 2 high temp solenoid valves or stepper motors, plus associated wiring could probably not be justified just on the merits of sound output. The reduction in back pressure would not make any performance improvement so the solution really would just be for sound.

I would tend to opt for a vacuum controlled system where engine vacuum, high at low throttle would close a valve and as vacuum reduces, exhaust pressure opens the flap valve.

Maserati I believe has a similar system and I was advising a performance exhaust manufacturer recently on how to do this on a Maserati 4200GT.

8Tech.