Exhaust comparison - Oem vs non res vs res

[Rw@@dy]

Sorry if I'm asking the same question that's been asked a million times before but I'm trying to weight up if I should make he change and to what type. I had a non res on my r32 and it was too loud in the car for normal driving, sounded amazing though! Does having a valved exhaust make lots of difference inside the car? And in saying that, what effect does that have on res vs non res with valves closed inside the car?

[adsgreen]

Certainly takes the edge off.
For reference on the outside 1m 45 degrees I registered 89 valves closed and 98 valves open at 4.5k revs.

The only bad noise is the resonant drone and this is between 1500-2200 ish rpm.
Slight tweak to driving style and it's not a problem.
On the rs4 I simple multiply speed by 10 to give the gear and that avoids the drone.

[surfpunkian]

Certainly takes the edge off.
For reference on the outside 1m 45 degrees I registered 89 valves closed and 98 valves open at 4.5k revs.

The only bad noise is the resonant drone and this is between 1500-2200 ish rpm.
Slight tweak to driving style and it's not a problem.
On the rs4 I simple multiply speed by 10 to give the gear and that avoids the drone.

Damn Ads, that's a great, concise answer - I do wish the forum supported "like" type function on a post [THUMBS UP SIGN]

[Youngben]

When i got my exhaust there was no option for no valves which was annoying but hey ho! I fitted it with valved disconnected and ran for months and it did get on my nerves eventually so thought i would try connecting the valves up and see what it was like. And the difference is night and day! its so much better for normal driving and with the S mode activated the exhaust always sounds like it did with the valves disconnected. Im 26 and love noise but i wouldn't be without my valves now! This video is with valves open...

http://www.youtube.com/watch?v=s3_GUJs3Io4

[sakimano]

On the rs4 I simple multiply speed by 10 to give the gear and that avoids the drone.

Huh?

[sakimano]

Resonated gets my vote

Nice clean sound. No rasp is key

[adsgreen]

On the rs4 I simple multiply speed by 10 to give the gear and that avoids the drone.

Huh?

yeah typo - divide by 10.

[PetrolDave]

The only bad noise is the resonant drone and this is between 1500-2200 ish rpm.
Slight tweak to driving style and it's not a problem.

I'd seen this said a lot before I went for a non-res valved in the Summer, and have to say after 6 months I think "slight tweak" is a major under statement.

Around town and when just pottering (e.g. on holiday) I used to spend 90% of the time between 1500-2200 rpm in non-Sport mode using the torque, but I just can't do that now as the drone is, to my ears (and especially to my wife's ears),really intrusive. So I've had to adopt a completely different driving style when pottering, instead of being in 5th or 6th gear I now use 3rd in 30 limits and 4th in 40 limits in order to get the revs above the drone (2200rpm+).

Needless to say whenever I'm out on my own it's Sport mode on and grin all the time.

But I have to say that IMHO a non-res has deleted one element from the RS4s armoury - it can no longer comfortably waft along in a high gear in town. That's been especially noticeable for me this year as we've had 2 close family funerals where I've had to be the first car behind the hearse & limo, and sitting in the drone region was too noisy but sitting above the drone zone got looks for using "such high revs".

[P_G]

The solution I found by accident to the non-res drone at 1500rpm was to fit a GruppeM. For whatever engineering related reason the combination of induction noise and air flow cancelled out / diminished the drone and I still pottered around in 6th at 30mph. Or you could Dynamat your car if you also were looking to improve the ICE sound quality

[adsgreen]

The only bad noise is the resonant drone and this is between 1500-2200 ish rpm.
Slight tweak to driving style and it's not a problem.

I'd seen this said a lot before I went for a non-res valved in the Summer, and have to say after 6 months I think "slight tweak" is a major under statement.

It is a slight tweak really - you generally drop one gear over what you would have otherwise have done.
the key is working out if this works for you. It does pretty much work out that gear to avoid noise = speed / 10. so 1st up to 20, 2nd 20-30, 3rd 30-40, 4th 40-50 and from 50 onwards you can just get away with 6th. I'd always advise any prospective owner to run around using the above pattern to see how they get on with it.
Whilst it's nice to stay at 1500 it's not something I like doing as to my mind it's outside the best operating range of the engine and just puts extra stress on things. 30mph in 5th just feels wrong to me but that's just my view.

[PetrolDave]

It is a slight tweak really - you generally drop one gear over what you would have otherwise have done.

I stick by what I said - for me I'm having to drive 3 gears lower (not one) in 30 limits to avoid the drone - and that is not a "slight"tweak in anyone's language.

Whilst it's nice to stay at 1500 it's not something I like doing as to my mind it's outside the best operating range of the engine and just puts extra stress on things. 30mph in 5th just feels wrong to me but that's just my view.

That's not a view I share - if you have mechanical sympathy you can feel when an engine is starting to labour and you should change down a gear, for me that's closer to 1000rpm than 1500rpm in the RS4. But I guess we'll be agreeing to disagree on this one (and it's a point that's been discussed at some length over the last 7+ years I've been on this forum).

[adsgreen]

have you considered a diesel?

[PetrolDave]

have you considered a diesel?

Have you considered that other opinions are as valid as yours?

I absolutely love hearing a V8 doing 8600rpm (which is where MRC moved the rev limit to in the Summer), but I also use my RS4 as an everyday family car not just as a "high days and holidays car" so it has to be multi-faceted and not just a high rev screamer - which the huge flat torque curve allows, but the non-res has reduced the usefulness of that flat torque curve. Enough to consider having the non-res swapped to a res? No, but enough that I think others considering a non-res should be made aware of the reduction of usable flexibility, which I have always seen as yet another of the great characteristics of the fine RS4 engine.

Now let's just agree to disagree on this in a sensible adult manner.

[Ian_C]

Fecking hell, yours revvs to 8600!!!!

Must admit Dave, I'd forgotten you'd gone non res - rock on!

[adsgreen]

have you considered a diesel?

Have you considered that other opinions are as valid as yours?

I absolutely love hearing a V8 doing 8600rpm (which is where MRC moved the rev limit to in the Summer), but I also use my RS4 as an everyday family car not just as a "high days and holidays car" so it has to be multi-faceted and not just a high rev screamer - which the huge flat torque curve allows, but the non-res has reduced the usefulness of that flat torque curve. Enough to consider having the non-res swapped to a res? No, but enough that I think others considering a non-res should be made aware of the reduction of usable flexibility, which I have always seen as yet another of the great characteristics of the fine RS4 engine.

Now let's just agree to disagree on this in a sensible adult manner.

Jesus h Christ... It was said tongue in cheek hence the smiley...