Just had a Milltek fitted

[philroach]

i have an avant , started with non-res , now with res
big difference in noise from standard outside , nice inside , couldnt cope with the drone , goes right through your head below 2500 revs under load , which is a regular occurence in traffic
if u r going for a remap , still trying to decide myself , get rid of the precats etc etc , go for it !!!!

[bilko1]

The only cell I know is in block H.

That's a blast from the past

I have non res and decat and I get a slight drone at 1500 - 2000 but it is bearable maybe the twin pane glass helps. Tbh I want It louder as it still seems quiet, maybe it's my age and hearing.

[Mr Footlong]

Christ they had some ugly women in that show.

I am confused (shocker) after reading Dave's post. I was led to believe that by fitting the Milltek 100 cell DP cats to my car along wqith the Milltek system, that all the other cats were removed and these 2 100 cell jobs became the only cats in the exhaust system?

[el_ringo]

If you are getting a drone then you are not going fast enough. It must always be roaring!

[Mr V10]

Mate hammered it past, it sounds great, but it did before the Milltek too. It's a smidge louder, really not worth the price they charge new IMO if you've already got the factory plus exhuast. It would probably be worth it on a an RS6 that had a standard exhuast. Will take Amanda's car out tomorrow and see if non res is for me, if not I may go back to the standard sports exhuast and sell this Milltek.

[bilko1]

Decat and non res should keep you happy for a bit, you could always go for 100 cell cats but the Milltek ones are way over priced IMHO, you can buy 100 cell universal cats for £150ish each from motorsports shops. I personally love the sound of Bams but I fear it would draw unwanted attention from the rozzers.

[bilko1]

If you are getting a drone then you are not going fast enough. It must always be roaring!

Are your cats from Milltek?

[rossi46]

There are two stages of catalytic converters on our beasts - usually referred to as Pre-cats and Main cats

First there are precats in the down pipes - IIRC these are 200 cell (in each pipe).

Then the main cats in the box under the car are also 200 cell IIRC - so total (in each exhaust) is 400 cell

There are various different combinations of removal that people seem to go for:
- removing the precats, which frees up air flow in the downpipes allowing faster turbo spool up (total left 200 cells)
- replacing the main cats with 100 cell "race cats" (total left 300 cells)
- both the above - which is about the max one can do and stay within emmissions limits (total left 100 cell)
- remove everything - and be illegal!! (total zero!!)

It seems that some folk have left the pre-cats in, but then gone for 100 cell race cats - personally this doesn't seem logical as it leaves the 200 cell pre-cats in the DP's, and these create the biggest back pressures.



Any of the above should only be done with a modified ECU - otherwise you will actually lose power, and have a dashboard lit up like a Christmas tree!

OK - now Shop will correct the number of cells!!




Dave

Thanks for the post Dave - Think I've got it now !
All I would say is that I was always under the impression an amount of back pressure was needed to ensure correct spooling of the turbos - Going back a while, whilst doing some mods on a turbocharged Volvo 850,the supplier of a new 3" downpipe was asked ' why not just make it 4"/5" ? ' Their reply was that it would remove too much back pressure from the system and that would ultimately be detrimental to performance.
Aren't Milltek 100 cell cats something like 2k ! ??

[Daveperc]

I was led to believe that by fitting the Milltek 100 cell DP cats to my car along wqith the Milltek system, that all the other cats were removed and these 2 100 cell jobs became the only cats in the Exhaust system?

Just had a browse round the Milltek site. It looks as though you are right - their 100Cell sports cat product includes larger downpipes (presumably with nothing in) plus the 100 cell cats.

So this is about the minimum street legal set up in terms of cats.

I was always under the impression an amount of back pressure was needed to ensure correct spooling of the turbos

Yes, you do need some - but not as much as the stock exhaust gives.

However to take advantage of the lower back pressure you need the map to be optimised to suite the set up - ie Stage 2.

Dave

[Dipper]

Not sure that's correct. I know back pressure is important in NA cars but iirc from my impreza days you want as little back pressure as possible on turbo cars.

[HYFR]

There is plenty of drone in the non res..

must be gettin old mate

i've had x3 non res examples and none of them droned

[Mr V10]

Eitheir way, the plus exhuast is basically a non res Milltek. If you've got a plus, stick with your OEM one IMO.

[HYFR]

Amar, I found my plus sports exahust much quieter than my NON res

[Mr V10]

Thats good to know. Once I've had a spin in Amanda's tomorrow, I'll decide if I can live with the drone or not!

[HYFR]

mate, come for a spin in mine and then you'll see what drone is !!! hahahahaha