I've finally had the remap done at AMD.
Went for the 'Stage 2', which comprises the Milltek cat-back exhaust system, and remap. Also had the Viper diverter valve fitted. All in was around 1200 after VAT.
First impressions were that I could definately hear the turbo sucking more air in, and presumably because of the increased boost, the diverter valve is quite a bit louder. The exhaust was making a lovely deep, smooth burble at low revs, and was not at all intrusive. Just how I wanted it. I didn't want to drive like a fool coming out of Bicester, so I had to wait until I got on the B4100 until I got the chance to see whether it was up to expectations. So, with a good straight stretch in front of me I floored it in second at about 40mph.....
WOW! The thing just took off, and I couldn't help but keep going in 3rd, 4th....... /ubbthreads/images/graemlins/angel.gif It was quite a handful at first - the extra torque-steer required me to concentrate a fair deal. The main difference I noticed on the first few miles home was the extra torque in the mid-range, say between 3000 and 4000RPM. Floor it in any gear at that point and the acceleration is smooth, progressive and crisp, right up to the redline, and the torque doesn't drop off as rapidly as before the remap. It feels like it's breathing loads better. Had tussle with a Cooper S on the A43 - he did beat me eventually, but it was no walkover. I would never have contemplated going for it with a Cooper S before the tuning. (Maybe it was a 'Works' /ubbthreads/images/graemlins/grin.gif)
Then onto the M1. I found that the Milltek was a tiny bit louder than stock when cruising at around 80mph, and got louder when I squeezed the throttle, or lifted off. It gives a nice burble on the overrun too. It is by no means annoying or boy-racerish, just subtle and deep, but with much more character than the standard exhaust. Perfect. The tailpipes are big and fat and fill the recess in the S4 bumper superbly. It looks like it's been there since the day it left the factory. It's a very well-made exhuast as well as sounding spot-on.
I'd say that the power increase can be felt more in the higher gears, at higher speeds. No more dropping into fourth to overtake on the motorway, just foot down, slight pause, then a nice dollop of torque. It was very easy to get carried away. It now accelerates between 100 and 120 in fifth like it did between 80 and 100 in fourth before the remap. That's what has impressed me most. And I don't make a habit of driving at those speeds by the way; it was purely for test-purposes. /ubbthreads/images/graemlins/wink.gif
Now the only thing that I'm not too happy about is the power delivery through the rev-range. It's not that smooth when the turbo comes in; you can feel (and hear) it boost at 2000RPM, then it gives an extra shove at around 3500RPM. It seems a bit lurchy sometimes, but to be honest it sometimes felt similar before the remap. I think I'd be right to assume that any hesitation would be made more obvious with increased boost. Because of this I find myself waiting until at least 3000RPM until I nail it. Doing this seems to get power to the wheels much better. However I might have a go at cleaning the MAF at some point, or getting vagcom on it to see if it gives any error codes.
But I can assure you that it's not a massive problem, and I'm sure it's something that can be diagnosed and solved. And I will stress that it's not the remap that has caused it. Like I said, it sometimes didn't feel that smooth before the tuning.
Enough of the negativity. So yes, I'm very happy with it. It has given the car the extra grunt it needed from day one, and it's so much nicer to drive. It puts a grin on my face charging through the gears, and it really does gather speed much faster. Changing from 2nd into third at 6000RPM is magical - it puts you right on the sweet spot at around 3500RPM and keeps pushing past 100. Third to fourth is just as good. They are quite closely-geared anyway, so you're always on the power. Forth to fifth? To be honest I haven't had much of a chance to get to those kind of speeds, but let's just say that I would bet money on the car now having the ability to see 145 on the speedo. But I can never find a road long enough!
Power low-down is not greatly increased; the extra grunt is all high up the revs, but that's what I'd expect with a 20 valve four-pot. From 3500RPM upwards the difference is brilliant.
Right then, on to the torque and power increases:
Power before Stage 2 - 155.7 BHP @ 5814 RPM
Power after Stage 2 - 203.1 BHP @ 5549 RPM
Torque before Stage 2 - 158.2 lb/ft @ 3903 RPM
Torque after Stage 2 - 204.3 lb/ft @ 4646 RPM
The power has increased by around 48 BHP, which is better than I hoped for. Maybe the Milltek gave good gains? Who knows.
Torque is a little lower than I expected, but it is spread nicely through the revs, and delivers the goods.
The guys at AMD were very helpful and knowledgable, and I always felt that my car was in safe hands. In my opinion it was money well-spent and I'm glad I chose AMD. They have changed my car from reasonably swift to pretty damn quick, and I'm loving every minute of it.
Cheers.
/ubbthreads/images/graemlins/dancing.gif