Mike's Panther RS6 Performance thread

[Surrey Sam]

Yes, I deserve it.

[Andy_W]

So the explanation I was given today was straight pipes with No H or X will sound quite lumpy at idle. / low revs. The H and X pipes will smooth out the sound, X more than H but he felt the position of the centre box would make getting an X in tricky and produce a uneven flow.
Looking at Milltek their system is straight with no H or X. Akra says it has an X but it's in a centre casing much like the OEM.

I have heard a C63 this guy has done - full decat and centre delete H pipe and it sounds epic!!

[MikeFish]

Looking at photos of aftermarket cat back systems it is not entirely clear but I think you are right about them being resonators. I'll get them chopped out too then! Thanks

Basically what I've done (and what you're going to do) is the same as what a non-resonated Milltek is, bar the rear back boxes which we've kept as stock. There are no sensors around the questionable resonators so I assure you no issues will occur - and I've never had any issues with Audi whenever it's been in for work.
Not a problem my friend, happy to help. Let me know how you get on!

Ok, I think I've gotten to the bottom of it now. One Andy w called them resonators, the other Andy w called them secondary cats. I believe they are indeed secondary cats hence why you can remove them with no fault lights or MOT issues later down the line.
The milltek full system removes the primary cats in the down pipes, the places the sports cat (assuming you don't go cat bypass) under the car where the secondary cats normally live. Hence why they state you need sensor extension wires (cos they've moved the main primary cats from the down pipe position to underneath the car).
The milltek cat back system removes the secondary cats too.

So the question is, how restrictive are the secondary cats? Is there any noticeable power gain once they have been removed? Or do they only work when the engine is cold? And will I get a smokey exhaust when 1st starting the engine?

[Andy_W]

Looking at photos of aftermarket cat back systems it is not entirely clear but I think you are right about them being resonators. I'll get them chopped out too then! Thanks

Basically what I've done (and what you're going to do) is the same as what a non-resonated Milltek is, bar the rear back boxes which we've kept as stock. There are no sensors around the questionable resonators so I assure you no issues will occur - and I've never had any issues with Audi whenever it's been in for work.
Not a problem my friend, happy to help. Let me know how you get on!

Ok, I think I've gotten to the bottom of it now. One Andy w called them resonators, the other Andy w called them secondary cats. I believe they are indeed secondary cats hence why you can remove them with no fault lights or MOT issues later down the line.
The milltek full system removes the primary cats in the down pipes, the places the sports cat (assuming you don't go cat bypass) under the car where the secondary cats normally live. Hence why they state you need sensor extension wires (cos they've moved the main primary cats from the down pipe position to underneath the car).
The milltek cat back system removes the secondary cats too.

So the question is, how restrictive are the secondary cats? Is there any noticeable power gain once they have been removed? Or do they only work when the engine is cold? And will I get a smokey exhaust when 1st starting the engine?

Yes they are definitely secondary Cats. All the R8 aftermarket systems delete the secondaries and I never had any smoking or any noticeable difference. Removing them will provide a little less resistance and noise suppression I believe.
What's hard to work out is what is different between the standard exhaust and the OEM sports as there seems to be the same amount of cats mufflers etc. I guess just a bit less muffeling material in the boxes that's all.
Basically deleting them and the centre gives you a Milltek style cat back but with OEM back boxes. Same with Capistro. Only the Akra retains any mufflers further up the system.

[MikeFish]

I think you are right about the differences between the sport and non sport exhausts. The RS3 is the same, looks almost identical so probably just different internals in the back boxes.

My car is booked in for centre res and secondary cat delete on Friday.

[toshers]

I'm following this with much interest...

[MikeFish]

I forgot to update this thread when I had my exhaust modified. Unfortunately I didn't get any photos as I was in a hurry to get down to MRC to have it dyno'd.
He modified it in 2 section so either one of the resonators could be replaced at a later stage. To be honest i haven't even seen what it looks like yet!.
But it sounds incredible... Well, maybe not incredible, but it is exactly the right balance for me now between audible and not overly loud. No videos or recordings yet, but it is such an improvement. Really happy with it now.

Anyway, here's some photos from this morning:








Also, copied from the audio thread but thought I also add it here for future reference:
Earlier in the week I added an amp and sub to the boot. Makes a huge difference. And because it is an avant rather than a sealed boot of of a saloon the gain on the amp had to be turned right down (have no sepearate sub control yet, have to tweak using the bass setting on MMI and gain on amp). As the bass has been taken away from the door speakers it means the Bose amp / speakers can go louder without distortion.

So I thought I'd try to pop out the centre speaker grill in daylight this time. It came out easily enough using some trim tools. There are 2 bolts holding the centre speaker in (5.5mm which I thought was an odd size). I unplugged it then put it but bolted the speaker back in for safe keeping.
Initial sound difference was that it sounded much duller. It needed more volume to get the mid range out but as there is no control for mid range it means the overall volume needs to come up. So after turning the bass down further and turning the volume up it now sounds better. I played with the treble a little too but ended up with it back at the 4 o'clock position.

With the added bass and getting rod of that awful centre speaker I am much happier with the sound. Could I leave it like this now? Yes... But I know that will never happen.

I had a go at popping the tweeter covers off and they started to lift but seemed to click rather than pop out like the centre channel so I pushed it back in before doing any damage. I'll take a look on ELSA to see if I was going the right way. My goal was to see if I could easily drop in some better tweeters because the mods have now highlighted these as the next weakest point. Also, it is in dire need of some proper equalisation. I almost installed my processor this week to give me that ability but it would mean full amplification from my aftermarket amps and having to use a high-level input rather than a low level or, even better, a digital signal as is possible with pre facelift cars.

No photos of the amp install yet, but it's not pretty. I butchered the plastic cover that sits in the spare wheel weel to make an amp mount. I'll take some photos when it comes out to be carpeted.

[kmpowell]

Earlier in the week I added an amp and sub to the boot. Makes a huge difference.

Lowered, check. Illegal number plate, check. Aftermarket exhaust, check. Amps, check. Sub in boot, check. Go...

[Surrey Sam]

I was wondering why Mike had a skipping rope in the boot?

[Eddie555]

I was wondering why Mike had a skipping rope in the boot?

That would be a length of Phoenix Gold subwoofer speaker cable. It also doubles up as tie cord for his b1tches.

[boff]

I'm right in the mood for a bit of Ali G tonight now....

[MikeFish]

Aaaaiiiiigghhhhtttttt, for real. Ride da punani.

Great film.

My car is wicked, wicked, jungle is massive!

[boff]

Chicken dipppers!

[MrBadger]

kmpowell that made me laugh out loud- properly.

[MikeFish]

I popped the tweeter grills off the other day and removed the tweeters. I was surprised to see a capacitor on the back of the tweeter meaning that the output from the amp is not filtered in any way and I'd need to add a crossover before swapping it out for one of my aftermarket tweeters. Trouble is, I can;t fit any of my crossovers into the hole in the dash. I might just follow Audi's lead and attached a capacitor to my tweeter for now.
It looks like fabricating a little adapterplate to mount any aftermarket tweeter should be straight forward, I traced a template around the actual tweeter. It would be very easy to just hot glue the tweeter to the underside of the grill but I think I would prefer to make a couple of mounting brackets.