Milltek cats & downpipes.....again!

[Verruckt]

Yes, you will need to re-locate the secondary O2 sensor to just beyond the main catalyst otherwise you will cause a warmup catalyst efficiency code.

Is this difficult for a garage to do - I mean do you have to drill and tap a thread into the DP?

TIA.

It should be easy. The only thing to be mindful of is that you must align the two bungs so that the O2 sensors do not hit each other or the driveshaft.

[Dippy]

Dippy,

Acceleration in the top end much improved after installing the Milltek cats, but it just doesnt feel linear all the way to redline...tapers off after 5.5k as i said. Engine gets hot after runs at high revs which i would have thot is very normal. OK, here in Asia outside temp hovers at 30 celsius + in summer, but this time of yr it's mid teens to low 20's. Sustained high speed/engine speed runs during winter my oil temps rise to 110 (but drops very quickly since i also have an aftermkt oil cooler installed.) Do u get cooler temps with yours after hard runs?

Also, lastly, do u think i should pay to upgrade my MTM programme to the sport cat stage? OR shld it be free? Thx

Only you can answer if it gets hotter than it was before. This what I noticed in the week or so I had after the cats were fitted and before the new remap.

However you have an answer already with the power tailing off at the top end. I checked this again on my car last week: I did some hard accelerations all the way to the redline (in various gears), and I did not feel any lessening of acceleration until the rev-limiter cut in.

My comment about a free remap was specific: If you have a stage I remap done by a given tuner and then later go back to buy and fit cats, you should ask for (and expect) a free remap (in my opinion). Your chances are less after the event. However I am speaking about a tuner who does their own mapping (like AmD in my case). For MTM distributors, a remap means they have to pay MTM (I assume either a new chip or a license for the new software), so I doubt it would be free.

[moktoya]

Point taken, many thx Dippy!

[tricky]

Hmm, I'm interested in the DIY route for removing the precats, but as was asked earlier is there any instructions available start to finish that can be followed? I don't normally take cars apart and practical though I am I would really want some proper guidence if I were to try it. OR would a garage be able to do it? And if the car isn't already remapped would it then require a post remap, or could you do this to improve stock performance also?

[sash]

I think the DIY way of drilling out the pre cats sounds great. Found a decent guide, no pics though.
http://www.audizine.com/forum/showthrea ... adid=14303

Verrückt, does that guide look right to you?

[Nige_RS4]

Good link - thanks.

I love the way that step 1 simply says "remove the DP's" ~ LOL!