Shortly after finishing the dashboard upgrade I decided that I would upgrade the Emerald ECU to the latest firmware version, called the K3. To do this the ECU was sent back to Emerald and they performed the upgrade and returned the unit with 3 days!
All the connections remained the same, so it was simply a case of plugging the unit back into the car but I wanted to make use of one of the new features that required a bit of extra hardware to be fitted to the car.
Switchable maps appealed for a couple of reasons. The first was that I could have one map for normal driving on short blats, another slightly more economical map for cruising and one spare map, which I could use for guest drivers/MOT with a lower rev limit imposed. To fit the switch I was able to reuse the old heater control cable hole and you simply add a single cable to the ECU connector. This is taken to the switch, with 3 positions of the switch being taken a) to earth (0v), b) to earth via a resistor (2.5v) and c) to nothing (5v). You then configure the different voltages in the Emerald software. Very simple and works very well and it is happy to switch whilst you are driving along with no discernible signal.

The main reason for the upgrade, however, was the introduction of self mapping, or as Emerald call it, Adaptive mapping. I used something similar on the Megasquirt ECU and it worked quite well, but it's major drawback was the fact that due to the limited number of 'writes' that the EPROM could handle, you could let it self learn, else you'd end up with a half mapped engine with an EPROM that wouldn't allow any more updates. To get around this, you had to run the car with the laptop on the passenger seat and then only do a single 'burn to ECU' at the end of a run. It wasn't a major problem, but it was a pain to have to fire the PC up everytime you wanted to go for a mapping run. The great thing about the Emerald system is that you get 4 maps:

Injection Map The normal fuel injection map
AFR Target A map for each load site where you enter the AFR (or lambda) target - e.g. at light throttle and low rev you could use a figure in the low 14's or high 13's, but at higher throttle and revs you would want to run something in the lower 13's.
AFR Corrections This is where the ECU stores the values that it has corrected so far - so each load site has a +/- figure representing fuel added or removed from the main map. This is read in conjuction with the main map so when returning to a load site, the corrected value is used and corrections are then added or removed from the new starting point.
You can select correction values in the map and right click and apply them to the main map, but you only need to do this every now and again, just to keep the main m
Feedback Mode This is where you can select, on a per load site basis, how you want the ECU to act. It can run in open loop where it ignores the lambda sensor completely, closed loop where it targets according to the AFR target map but doesn't record anything in the Correction map or Adaptive, which is the same as closed loop, but it stores the correction made for next time.

I found this worked very well, once I figured out, with the help from some Blatchat members, how to set the various settings, like response speed, etc.
One of the other new features of the K3 is the fact that you can change the load site values to what you like, so the rpm and throttle positions can be changed to 200rpm gaps, or whatever you like. I did this when I got my ECU back as the 500rpm gaps of the old version meant that I was only using half the map. The ECU then interpolated the new spacing and gave me a map based on the old one. When I first drove the car with the K3 it was running very lean up to around 3000rpm and I initially thought my AFR sensor was playing up as it wasn't like that before the upgrade, and I had fitted the dashboard in-between, so may have altered something. After some trials I found it wasn't this and it must be the map. I added some fuel in the problem areas and switched on the adaptive mapping and went back out - hey presto, which it as a bit rich to start with, you could feel the engine getting stronger if you held the throttle still and it simply got better and better. Great!

However great adaptive mapping may be, I still felt that I should get the car on a rolling road - there are parts of the map that you enter so rarely that it doesn't have chance to correct (like high rpm, or high load but slow rpm) and I had no way of knowing if my ignition was anywhere near close. I booked a session at Emerald and then waited the 8 weeks for it to come around - that's how busy they are. I set off early in the morning for a gentle drive around the M25 and up the A11 and I arrived 3hrs later, just after 9am. Dave Walker was there and moved a project car out of the way so I could back my car into the torture chamber and then made me a cup of tea. Things got under way around 10am and Dave worked his way through the lower rpm sites, checking the fueling, adjusting it further up if you spotted a potential problem, etc. He was very methodical, I suspect from having done so many car now, but it was very interesting to watch, and you just can't expect to be able to hold load sites in the same way on the road whilst trying to drive at the same time. He worked his way up to 5000rpm and then went for the first power run. This was the moment I had been dreading for two reasons: a) it might blow up and b) what if it made some abysmal figure, far less than expected - Id be gutted. I kept telling myself that I would be happy if it made 190bhp and really happy if it made 200bhp - but really I wanted the magic 200bhp - it just sounds so much better doesn't it.
On the first run it made 196.4bhp - great, that isn't bad for a first attempt and fear number 2 was crossed off my list. Dave went back and added some advance and tried again - 198.6bhp. Getting there, so a bit more was added and he took it a bit higher on the revs this time and got 201.4bhp. One happy bunny and the car was intact, which was a bonus. Dave proceeded to check the fueling out from his data read-outs and make some more adjustments and at around 1pm he declared it done.
On the trip home the car felt a lot nicer to drive. Whilst I was, again, only on the motorway, I could feel that the engine had loads more power at light throttle due to all the added advance and I was maintaining my speed with a noticeably lighter throttle. I brimmed the tank shortly after leaving Emerald and again when I got home and recorded 33.5mpg - which wasn't bad as I hit some traffic on the M4 and had a play with a Ferrari F355 as we were both bored.

 
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