Downpipes and straight through exhausts

[viperbl]

Does anyone know the width of the RS4 downpipes?

I assume that 3" downpipes are wider and the optimal width?

Also, how loud would an straight through exhaust be? ie, just a pipe(s) from the downpipes to the back, no box or anything inbetween?? Anyone done this?

As for the 3" downpipes etc, can these be bought off the shelf and fit straight on to KO4's or do they need to be custom made?

Can anyone recommend a company to make the above? prices etc?

[MarkB]

MRC do the 3" downpipes AFAIK

The RS4 downpipes are 65mm I thick, if you want I can confirm for you, they're just sat in the garage...

Doug was running about 99/100 db at the noise test Saturday with I think just a rear box on his duel system.

[viperbl]

MRC do the 3" downpipes AFAIK

The RS4 downpipes are 65mm I thick, if you want I can confirm for you, they're just sat in the garage...

Doug was running about 99/100 db at the noise test Saturday with I think just a rear box on his duel system.

Cheers Mark,

so thats around 2 1/2 inches ...

My thinking was, depending on price, get a nice striaght through pipe for max performance when needed but a quiter proper exhaust for every day driving, if changing from the downpipes it should not be too difficult or time consuming to change over ...

[s4woody]

RSfabrication made leons exhaust system and i believe doug's and maybe flashG's...sounds awesome..although leon was thinking of having some sort of extra baffle or noise reduction box fitted cos of the sound/drone..

[flashyg]

Rs exhaust is top quality, I went for 2 boxes and it is utterly civilised but still damned loud.

[MarkB]

My thinking was, depending on price, get a nice striaght through pipe for max performance when needed but a quiter proper exhaust for every day driving, if changing from the downpipes it should not be too difficult or time consuming to change over ...

Aren't most 'events' noise restricted though?

With the amount of air I should think your turbo's are trying to shift you should see a resonable gain by going for larger downpipes and exhaust.

[DavidT]

Most events are 98db standing, some are 98db driveby. There are very few at 105 or unrestricted.

My car is pretty loud but only read 95db at the noise test on Saturday (Milltek downpipes with 100cel cats & Milltek Dual). Dunno what Doug's was but he obviously passed and was sounding good as it went by the pits. Unlike any other B5 thats for sure

[MarkB]

I was told his read 99db before going out. He got called back in to test again and read 100db but they still let him back out.

He was running one of the loudest cars there and did sound quite different to all the other B5's

[viperbl]

Aren't most 'events' noise restricted though?

With the amount of air I should think your turbo's are trying to shift you should see a resonable gain by going for larger downpipes and exhaust.

That is true, but the hillclimb out here I think is unrestricted ... can't remember any testing gear last year, and there where one or two very noisy cars ...

I think the Milltek I have is not very good, as its quite restrictive???, its getting on a bit now, one of the first mods I did ...

Picture if anyone can confirm ...

[MarkB]

That does look quite used. I think you need to get a quote for an RS Fabs system. They do look the well made and should flow extreemly well. Think you'll need to go through MRC for it.

[DavidT]

I think someone on here will have the Milltek too

[viperbl]

I spoke to Doug about RS when at the ring, and I thinking they are looking like the best choice for this ... although, could I live with Doug's exhaust? Not sure, its pretty dam loud!!

I did see a neat little trick with a Germany RS4, he had a remote control which closed off one of the pipes! and certainly reduced the noise for pottering around town ...

[MarkB]

Is Doug running a single box or dual?

I couldn't/wouldn't want to live with that much noise.

[DavidT]

Nor could I, mine would be too loud if I had to drive every day.

[viperbl]

Is Doug running a single box or dual?

Single I believe ...