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Phil S1

Emerald Installation And Rolling Road Mapping

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Following on from my recent engine upgrades and the subsequent MEMS ECU problem, detailed in my previous ‘Sabre Heads KR1’ thread here:-

http://www.midlandslotus.co.uk/forum/topic/61378-sabre-heads-kr1-plus-newman-phase-2-cams/ here’s an account of my Emerald installation, which should hopefully resolve everything….I reckon this will definitely be the last mod for quite some time…probably!

This is very much new territory for me since I don’t know the first thing about programmable ECUs or setting them up but here goes....

I ordered the Emerald from Roger at Sabre Heads (he’d previously told me he could offer one at a competitive price) and it arrived direct from Emerald within 48 hours:-



I provided Roger with all the details of my car, although he pretty much knew the spec already, seeing as most of it was of his doing. He then ensured the Emerald came preconfigured with a map best suited to my particular car. If you’re familiar with Emeralds you can order a ‘Generic’ ECU which you have to pretty much set up from scratch. A ‘Preconfigured’ one like mine comes with a suitable map already loaded and takes a lot of the hard work out of the initial set up. It doesn’t cost any more either.

I installed the software provided on the CD onto my laptop and had a read through the guides. (you can also download all the files direct off the Emerald site too). The comms lead between the laptop and Emerald requires a laptop with a serial port, if you have a newer laptop then you probably won’t have one, so you will also need a serial / USB adapter. From what I understand there are a multitude of cheap adapters out there that won’t work. You’re probably best advised to buy the one recommended and sold by Emerald, although I think any that has an FTDI chipset should be okay.

Before doing anything on the car I first of all mobilised the alarm system and then swiftly disconnected the car battery before it self-immobilised again.

Emerald recommend that both the coil and the injectors are disconnected too. They must be some of the most inaccessible plugs to get to in the engine bay, particularly so if you have the VVC plenum like me.

The coil is on the rear facing side of the engine, about half way down and underneath the intake ports, you can just about see it from above as in this photo:-



To disconnect it, unless you’ve got snake-like arms, you really need to come at it from underneath, so time to take the undertray off I’m afraid.


The injectors are slightly more accessible, you can at least see them:-



The problem with these is getting to the retaining clip on the plug. It needs to be depressed upwards before the plug itself can be withdrawn rearwards.

What worked for me was to use a length of garden wire, slid underneath the clip and then levered against the cast intake whilst simultaneously using a large flat bladed screwdriver to prise the plug rearwards. Here’s a photo showing the wire:-



I didn’t have enough hands to hold the wire, the screwdriver and focus the camera all at the same time but hopefully you get the general idea.


With those all disconnected I then undid the 3 screws that secure the MEMS ECU to the boot divider and after a bit of a struggle finally managed to unplug the multiplug from the ECU itself:-



The Emerald has the exact same plug connector so it’s literally a straight swap on the S1 Elise. I believe it’s a bit more involved on the higher spec cars with different ECUs like the S160, Exige and 340R, requiring some rewiring of the multiplug itself. (Glad I’ve not got one of those then!)

Here’s the MEMS ECU side by side with the Emerald, notice the MEMS unit has the vacuum pipe connection which I’ll no longer be using in my configuration:-



The vacuum pipe connects to the plenum via this vapour trap which, along with the pipe itself, are now redundant:-



I had seen a thread on Seloc where the Emerald had been fitted vertically with the loom plug at the bottom and the comms port at the top:-



I didn’t like this set up because it meant the loom plug was hard up against the big multi-plug connector that sits directly beneath it and it leaves the comms plug open to water ingress.

With a small amount of manipulation of the loom it’s perfectly possible to mount the Emerald horizontally like so:-



With the Emerald in place I was now about ready. I followed Emerald’s ‘Quick Start Guide’, connected the lap top and first of all saved the configuration and base map to disc. The guide then leads you through an overcheck of the fundamental areas of the ECU configuration to confirm everything looked right for my engine configuration, which it did.

Next step was to set the throttle position sensor which is purely a matter of manually applying full throttle and then releasing again, such that the ECU knows the full extent of throttle opening.

After that I was ready to crank the engine, the coil and injectors are still unplugged at this point. There’s a light next to the comms lead output on the ECU and this should change from red to green when the engine is cranked over and you should also see the engine speed being displayed on the lap top screen. All was good on that front so I then re-connected the coil and injectors.

I turned the key again and the car was firing but not picking up, I had to follow the guide and make a few adjustments to the injection trim until it fired up and established an idle:-



So, the car was at least running but was going to need some more work from me but more importantly the rolling road chap. The car is driveable but at the moment it doesn’t like starting from cold and it is pinking under heavy load so I’m driving it steadily until I get it properly mapped.

Emerald state that the K6 is waterproof but with my installation being in the engine bay rather than the boot I still wanted to provide some form of protection. After a bit of thought I had an idea, did a bit of rummaging and found a piece of polycarbonate. From my r/c model car racing days, back in the early 80’s, I knew you could bend polycarbonate:-



With the careful application of heat it will gradually start to soften and bend, get it too hot and bubbles will start to form within it.

Having first made a template out of card:-



I then cut out a rectangle from the polycarbonate sheet and marked where the 2 bends needed to be. I then clamped along the fold line using a couple of lengths of wood and gently heated it with a hot air gun:-



First bend successful, I then did the second. A bit of filing and sanding round the edges and a couple of slots and the shield was done:-



I bolted it in place using a couple of button head screws, washers and nyloc nuts:-



The slots and use of nyloc nuts to adjust the tightness means it a doddle to slide the cover out of the way to gain access to the serial port:-



The next step now is to head off to the rolling road, more on that soon....

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Nice job. Certainly easier than wiring it into the 340R - have to cut the original loom plug and wire on another.


Which RR are you using?

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Sorry, just not had chance to get round to it, rest assured it's certainly not charcoal but it's not 200BHP either.

I'll update you later this evening...

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As promised, here's the update following yesterday's rolling road session....


Many people make the journey to Dave Walker at Emerald for their mapping but he’s some way away from me so I chose to use one of their approved dealers instead. John Sleath Race Cars is a mere 40 minutes away from me, on the outskirts of Doncaster. He is tucked away on a farm, up a long gravelly and, it has to be said, somewhat pot-holed drive. John assured me it was going to be repaired in the very near future though, in case anyone else wants to pay him a visit. There was a whole host of machinery lurking in the many outbuildings as I arrived, mostly of American origin and of course with V8 engines. V8’s are very much what John specialises in and has built his reputation on. There was also something a little smaller parked up…his bright yellow Ultima GTR, currently for sale. I didn’t dare ask the price, but I couldn’t refuse the offer to have a sit inside. Apparently it used to have around 850BHP but John said it was simply undriveable on the road. He’s now fitted something in a little bit more manageable, it still puts out a good 400BHP at the wheels though!


Guided by John, I backed my somewhat diminutive and inadequate 4 cylinder machine onto the rollers, after which he set about anchoring it down and getting everything set up. John is very down to earth and more than happy for his customers to be as ‘hands on’ in the process as they like. He doesn’t have any fancy reception area or waiting room with drinks laid on, so best take a flask and sandwiches if you’re going to be there for any length of time would be my advice.

With the car all set up it was then a steady process of John running the car at various speeds, watching what all the parameters were doing and making adjustments as and where necessary. Within the first few minutes we both heard the pinking I’d encountered when I first drove the car after fitting the Emerald. A few more adjustments and he soon had that dialled out. After a good couple of hours we were onto some high power runs and some somewhat more respectable figures than previously.

Many of the car’s that John works on aren’t road registered but whenever they are he likes for the owner to take the car out, with him in the passenger seat and see how it feels in the real world. So this we did, and with the laptop still connected John was able to check and adjust the car’s road manners in real time. It pulled really well from the off but we did later encounter some low speed drive train shunt at around 1800-2000rpm. He made some further adjustments which lessened this but as yet has not fully eliminated it. It may be a characteristic of running with the Newman cams but I’ll put some miles on it and see how it goes for now and then maybe revisit it at a later date to see if we can improve it some more.

The main thing is, albeit in the few miles I’ve driven so far, there’s been no recurrence of the misfire at high revs I had seen previously with the MEMS ECU. The car sounds better with the revised induction and pulls really well too.


So thanks must go to John Sleath for ironing out the wrinkles of my Emerald's pre-configured base map and gaining me some more performance in the process. In all, the mapping took 3 hours (well within the 4 hours max that John had advised) at £70/hr plus VAT.

And yet another thank you of course to Brian for re-visiting the vernier timing and giving me a few pointers with the Emerald too. (that was more than a few hours at mates rates) cheers.gif


Donington on the 22nd of this month is now officially booked, so I'm looking forward to giving the car a 'proper' test then biggrin.gif


The figures you’re waiting for……I’ll be honest, not quite as high as other similarly modified cars have produced but I’m happy with the result nonetheless:-


153.8BHP with 140ftlb of torque.


I was only using 95 RON unleaded so I guess there may have been more to be had if I'd used something higher, I’m not sure.


Anyhow, here’s the new graphs showing power, torque and AFR:-



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Nice torque graph. I bet you are pleased with the result!


Is the rev limit set to 7k ?

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I think I am right in saying there is a soft limit of 7000 and a hard limit of 7200 Russ, although I'm not sure how that works in practice?

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My rough and ready maths suggests that is about 30% more power than a standard s1 makes, and with a nice meaty torque curve. I bet it will be tremendous to drive - still tractable low down, and you don't need to rev it ridiculously high to get the best from it so it should last longer too. A really nice conversion by the sounds of it. I'm a wee bit jealous!

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