Another update to the saga that is my S3

I finally paid a visit to
@Rick @ Unicorn Motor Dev. today and boy am I glad that I did! As mentioned earlier my plan was to get the ECU map tweaked to get rid of some over-boosting at 3k-odd rpm and generally give the map a look to see if there is any more power to be had. Additionally, I wanted to remap the DSG ECU for a while now and this would be a perfect opportunity for that.
The day started very early - 6am wake-up alarm followed by an almost a 3 hour drive from West London to Stockport (Some may say I’m mad to do this just for a remap, but it was worth it in my mind - Rick definitely knows his stuff amd after today, I doubt I'll let anyone else loose on my maps). The drive over was the usual M40-M6 drone affair with some pretty heavy rain at times, but nothing that the S3 couldn’t deal with
I arrived at Unicorn just before 10am and Rick got to work pretty quickly soon after that. First he did a couple of baseline dyno runs to get a feel for how the existing map was dealing with the new bits, understand what needs to be adjusted to get more out of it and get the DSG map on the car.
As expected the initial runs showed a huge torque spike due to the over-boost condition, but peak power was quite low. Now, as some of the people know, Unicorn’s dyno is one of the most pessimistic out there. Rick warned me ahead of time and said that it is known as a heartbreaker. I would call it pretty precise, mainly due to Rick's strict calibration regime. More details on that here -
http://www.unicornmotordevelopments.com/rolling-road-services.html Without wanting to start another dyno flame war, here is what the car delivered to begin with:
As you can see, the torque graph was all over the place and peak power of 362bhp was quite a bit lower than my expectations - my heart was definitely broken at this point. Rick being Rick, held his cards close to the chest and didn't want to promise anything at this point. I wrote earlier that after the recent engine work the car definitely felt much stronger and was capable of getting to freedom-losing speeds with ridiculous ease, but the main thing that confused matters as far as my butt dyno was concerned was that huge spike of torque early on. It made the car feel much more powerful than the original Stg2+ setup, but you could feel it let off after the initial rush kicked-in. That being said, Rick’s facial expression said it all - the map definitely needed a bit of work to get it where it needs to be.
So off we went, some dyno runs, then a tweak of the map, followed by another set of dyno runs, then another set of tweaks. I occupied myself with taking videos and photos of the process, peering over Rick’s shoulder and asking stupid questions, as well as admiring his collection of model cars in the reception:
After a few more runs and tweaks, power and torque graphs started to resemble something that was a bit better and power figures were beginning to look more promising, but we started to hit the limits of the current fueling system. Stock injectors were at their flow limit and because of the RS4 fuel return valve, we couldn’t increase fuel rail pressure to get more fuel through the more restrictive S3 injectors. This resulted in rather aggressive timing due to a leaner air/fuel mix and peak torque numbers being a bit too high for comfort. At least that’s what Rick said - I was a clueless oaf in that conversation
I asked Rick to setup map switching for me, so that in the unlikely event my wife needed to drive the car, I could put it into more or less stock power mode. What he did was setup a stock power map, then a normal boost map with very safe 372bhp/392ft.lb for daily usage (and extended high load use) and a more aggressive map with 403bhp/411ft.lb. Me being me, I picked the high boost one to use during the drive home (more on that later

). I’ve never had a setup like this, so was a bit excited about the prospect of playing with the options. Here are the graphs we ended-up with:
Normal mode graph (normal boost map) - 372.4HP/392.2ft.lb:
“Ludicrous” mode graph (high boost map) - 403bhp/411.1ft.lb:
In that last graph, you can see Rick restricting boost on purpose at the higher rev range to keep things safe - RS3 injectors would help cure that and release a few extra ponies there.
By the end of it, I was quite excited to go home and was over the moon to end up with a map that would give me 400+bhp, especially on a dyno that I trust to be pretty realistic. I know that in the end, it’s how the car feels and performs in real life matters more than a peak figure, but it’s nice to know what the car will realistically deliver. It’s like having a diver's’ watch that can withstand pressures at 200m underwater, but most owners of such watches will never take them there. Anyway, I digress…
The drive home was “interesting”... The high boost map was savage and relentless, with both power and torque being delivered in big, smooth chunks that made me feel like I hit the max warp button - I found myself grinning from ear to ear without realising how quickly I was arriving at some very unfunny numbers on the speedo. That, wet roads and the realisation of how many speed cameras there are between Stockport and M6 made me reconsider my earlier choice of map. I needed fuel, so switched to the 2nd boost map during a stop at a Shell service station. I know, I was being a wimp, but traffic was bad, weather cold and wet, and I didn’t want to find out just quickly I could lose my license, freedom or worse. The car just felt quite brutal and a completely different animal to what I had arrived in.
Don’t get me wrong, I was loving it and even on the lower boost map the car felt so much faster than before. Power/torque delivery felt very smooth, very OEM even. There was just so much of it and it kept coming way up in the rev range too! The grin didn’t get any less for the remainder of the drive home
I haven’t mentioned anything about the other mod that was made - the DSG remap. While the power changes are most noticeable immediately, it still made a significant difference to how the car drives now. I haven’t used the full manual or even sport mode so far, but D is so much better to use now: it doesn’t try to get into 6th at 30-odd mph, it seems to use gears more appropriately and the gear changes are a noticeably smoother/quicker too. Driving aggressively in D is actually much better - it feels less like an auto in that it seemed to end up in too high a gear pretty much all of the time, so that when you want a sudden squirt of acceleration it ended up being a bit slow to respond (paus, change down then go). Now it holds on to gears a bit longer, but doesn’t feel like it’s over revving the engine needlessly and generally feels a bit more refined. Now, it may be down to the fact that the car spent a good amount of time being ragged on the dyno for half a day, so I’ll see how it feels tomorrow, but so far, I like it and can’t wait to try out the launch control as well as the full manual mode. Pretty chuffed so far though!
The plan was that after today, my days of tweaking the power on this car are over. What actually happened was quite the opposite - I want a stable 400+bhp daily and to do that, I’ll need to work on getting the fueling sorted out. Rick said that we could bump the fuel rail pressure and switch to a 150bar fuel return valve, but running high rail pressures seems to cause high cam follower wear rate, so with that in mind, I’ll be looking for a set of RS3/TT injectors instead next year. This would increase fuel flow without increasing rail pressure. It’s a more costly way of doing things, but I’m not looking for shortcuts. That should be it… I think
