Difference between levels of performance is always about speed - both reaction and frequency.
Road liability is all about fuckwittery levels of mapping. Garbage in, garbage out.
Almost went down this road lots of years ago with the orange car, but it was about £5k to buy, and was advised a similar amount to map properly.
First car I drove with proper ABS/stability/etc and all it’s trickery was my 2002 Cupra R. Was spectacular in adding/removing braking/throttle to each corner, even grabbing a brake in a corner of the car when not touching the brake pedal. Remember doing a 150 metre slalom, 180 degree turn, slalom back, faster than a more powerful VX220, despite being almost twice the weight. After the first run through, you got used to all the juddering and buzzing, trying to stop you from killing yourself/it. If you turned it off, as in really off off, there was an enormous amount of smoke coming from the tyres, and a smell of melted plastic from all the cones underneath gently melting against the cats.
You could also play how many warning lights/beeps can you get on the dash at the same time.
Add 20 years development to this
This appears to be my level.
Ill let Fonzey play with the SCS kit for a bit and then decide the level of skill is far , far too high for me.
Luckily Bosch (and SCS) don’t really let you fuck with the strategies at all, but as John says. Shite in, shite out.
You need to preconfigure about a dozen parameters, stuff like:
Wheelbase
Wheel track
Weight of each wheel and tyre
Total weight of vehicle with driver
Wheel circumference with tyre
Etc.
SCS will preconfigure this for you, but via the CAN interface I’ve got for my ECUmaster stuff I can go in and alter it if I wanted to.
I’ve spent time this week getting the mechanical components of the install done. I hoped to have fluid in the system and partially bled before Christmas, but that’s fallen at the final hurdle today.
The main jobs for mechanical bits are:
- Mounting
- Plumbing
- Hubs/wheel speed sensors.
Hub’s as previously mentioned are from later Lotus cars, and come with the Bosch friendly 2-wire Hall Effect sensors.
I then needed to adapt the plug to connect to the SCS harness, luckily GM sell somepatch harnesses for this which I could use half of, then chop the end and re-terminate the other end.
Rear hubs slightly more complex than the fronts as the driveshaft is in the way. Still not a big job though, and soon got it swapped over.
This then allowed me to finally refit the 308mm discs to the rear which sort of set me off on this journey. 288’s back in the spare pile, 308’s back on.
Mounted the new plug adapters:
In terms of mounting the unit, I wanted to have it down in the HVAC cavity. Tidies everything up a bit, hides some mess and moves the weight a bit lower and central in the car.
There’s a plethora of rivnuts to use, of course none lined up - so added a few more.
Opted to use rubber isolation mounts as apparently the pump can get a bit rowdy.
There was a bit of ambiguity in the SCS manual about orientation of the pump. Older GenI manual stipulated that the outlet ports must face upwards, which matched the Bosch guidance too. The GenII one had no such instructions, so I queried with SCS who quickly confirmed I could mount it this way, I may just want to rotate it upwards when initially bleeding it to get any air through it cleanly.
That only left plumbing. I’d be retaining the factory hard lines to the rear of the car, so only needed to run about 30cm per corner from the ABS pump, then 2x30cm from the pedalbox via T Pieces for the pressure sensors.
The Master Cylinder fittings would be banjo type, for clam clearance. The rest would be plain old 10mm brake fittings. Easy, right?
I ordered some custom length pipes with the appropriate ends on them which arrived today:
I then spotted something which has halted progress, and has me quite confused. All of the 10mm fittings supplied have an inverted flare at the end, and a different outer flare seat angle compared to the other M10 fittings I have lying around, such as this old Goodridge brake line for instance:
I was supplied with these:
The outer angle also looks quite different:
This has me stumped. When ordering the lines I only had the option of m10 male, vs M10 female. The flare type is never specified, and as a result I assumed that M10 brake fittings represented a standard.
Obviously I’m wrong, and potentially have wasted a load of cash. The vendor insist that they are interchangeable, but I remain unconvinced. The angles are totally different. Maybe they will “work”, but I’m fairly sure they aren’t right.
At this point I’m really seeking advice/opinions. I think I’ll probably invest in some decent hard line kit and just commit to that once I return from my jollies.
I will at least need/benefit from flexible hoses connecting the pedalbox to the pressure sensors though as it gives me more options for clearance and routing - so when I order new hoses, I need to learn what I did wrong - and make sure that I order correct next time.
If anyone can:
- Identify the inverted flare fittings I was sent, and explain what they’re used for and why they’re different to every other fitting I have
- Confirm without doubt that they are interchangeable as per the vendor comments. I’ll need some convincing…
That would be massively appreciated. It’s hard to go back to vendor and say “you send me the wrong thing”, because all I did is click the option for M10 brake fitting, and technically they are M10… but there was no alternatives to choose from to represent the differing flares.
Advice appreciated!
2024 Update!
I vanished off on holiday for a couple of weeks from boxing day so progress was somewhat halted, but I did have some things trickling along in the background.
As previously stated I needed to free up some switchgear space for the new controls I’d be gaining. Though the 2-Eleven is swamped with drillable dash, I didn’t want to start drilling holes in it, and finding places reachable with the harnesses on is quite tough.
Lotus provided me with two switch panels:
Doorcard:
Dash (old pic):
Having the fog light separate from the side and dipped lights always seemed odd, but in hindsight I believe the fog light switch is actually the rain light for the race cars, so that makes more sense.
Plan was to rejig these two panels a bit, make room for more switches and knobs and minimise cabin disruption. I could have just started drilling holes and forcing switches in but the spacing would be all to cock, so I used it as an opportunity to learn my way around CAD a bit.
Laughable complexity I know, but these still took me hours!
Plan is to move all switches to the centre panel, and this frees up the doorcard panel for my three adjustment knobs: TC, ABS and Brake Bias.
The four small switches on the centre panel would be: side lights, dipped beam, fog lights, map switch. The large ones on either side would be the hazard lights (original location) and then the starter button, moved from the doorcard.
I added an extra cut-out in the centre panel for my data logger USB stick, as it was previously hidden away and a bit difficult to access and see at a glance if a stick was in or not.
With these drawn up, I had to decide then how to get them made. I did consider a 3D Printer, I’ve wanted one for ages and this seemed like an opportunity to get one in - but to be honest some large Ferrari bills made me reconsider my budget 
Next option was laser cutting. There are a few firms online that will let you upload a CAD file and get an immediate quote on the website. Some over in China are very cheap with very long lead times, so I used a UK one with still a moderate lead time but something that could be trucking along whilst I was on hols.
I had options to choose a finish, and clear anodising was one such option but that raised a flag for a bespoke quote - and so couldn’t proceed on the website. With that in mind (as I was doing this in the hours before departing), I just picked a raw finish on aluminium.
Sure enough, they delivered as promised and I had a nervous few days waiting to see if I’d messed my measurements up and had a 6 foot switch panel waiting for me at home.
They only bloody fit, don’t they!
The laser cut finishing is loads better than the Lotus punched out parts. I got two of each made (because adding these only added literal pennies to the order) so my plan is to paint a pair using the Lotus “almost chassis colour” paint, then look at sending the other two off for anodising somewhere when I can be bothered.
I still need to add decals/labels etc once they’re finished. @TitaniumDan I will send my original TC panel off today - I’ve not forgot!
Did a bit of work to extend the wiring for the starter button, but very little was needed to shuffle everything else around.
I’m dead chuffed with this result, it’s allowed me to sympathetically add what I need BUT there was still a couple more things I needed to find room for.
The ABS unit has a warning light and an on/off toggle switch. The warning light I’d originally planned to just coil up and hide somewhere, because any ABS warnings/errors will display on my dash via canbus. After two weeks of overthinking this on holiday I decided I’d rather have the idiot light displayed somewhere. CAN messages rely on the ABS ECU being healthy, so if there’s a fatal error with the system I’d really like to know about it so it can simply be toggled off.
Though I really don’t want to drill any aluminium, cheap plastic shroud panels are fair game because they’re somewhat readily available.
Toggle switch and MIL light added to the steering shroud:
Yes it’s the biggest warning light you’ve ever seen, might swap it out for something a bit more discreet… but it will do for now, will be visible whilst driving and the switch in about the only spare place on the car where I could reach it whilst driving!
Whilst the laser cutters were beavering away, I had two weeks to continue overthinking my brake line situation.
I’d heard from a few people, many car builders/DIY’ers, some people who worked in the brake plumbing trade and the general message I got would be that the HEL “universal” flare seats would be ‘fine’, but because the seat angles are different to the receiving fitting - they would essentially be cutting their own seat. I really didn’t fancy that in my quite expensive ABS unit to be honest.
After much deliberation, I decided to go back to my plan A which was to invest in some half decent flaring kit - and just make some hard lines up.
It does mean I’ve got a bunch of unused braided hose sat going to waste now, but hey ho. I’ll lob it on eBay, maybe someone can make use of it.
I bought a pipe cutter, pipe bender and flare tool along with enough M10 fittings for the job, and about 7.5m of kunifer(cunifer?) pipe.
Spent a couple of hours just mucking about playing with the tools and seeing how the flares looked.
Got some wrong:
Then read the manual and got some right:
I’d had to bodge some “tactical flares” in the past to rescue a clutch line on a non-Lotus if I remember right. It was using whatever tool the local Halfords had, and it was a right mess. Took ages to get a half convincing flare, but this tool once used properly was absolutely bang on. At time of writing I don’t actually know if any of my flares will seal, but they all passed the visual checks and none gave me that “uncertain feeling” when making them.
I did a few things through my practising to improve the flares including:
- Properly deburring the end of the pipe after cutting it
- chamfering both the inside and outside of the end after deburring
- annealing the end with a blowtorch, then immediately dousing in water
- greasing the tool, excessively
With these steps, I got to work on mapping out my pipe runs.
I picked some generic arts and crafty hand bendable wire up which was great for getting rough lengths and angles right:
Bender was dead easy to use, so over a couple of short sessions I got the pipes banged out:
Also bought this gizmo to help straighten the pipe off the coil, to remove that “home made” look to the pipes a bit.
WIP:
Doing the inlet pipes beneath the unit were easier in the kitchen, using some card to mock out the position of the t-pieces I’d be using for pressure sensors:
The inlets would then be the only place where I’d use the questionable braided hoses. The outlet from the master cylinders is a banjo fitting, so this doesn’t use the M10 universal seat that I’m nervous about.
At the other end, the universal seat screws into a cheap t-piece- so I’m less concerned about it “cutting its own seat”.
If these leak at first pressure up, then I’ll of course use something else, but we’ll see.
I’m pretty happy with how it’s all worked out. I’ve since added a couple of chassis clips just to suspend any pipework that may have vibrated into contact with something.
The only thing now stopping me from sticking some fluid in are my banjo bolts for the MCs. the 20mm bolts I picked up appear to be 1mm too long… so got some slightly shorter ones on order, then I can nip those up, stick some fluid in and then do a preliminary bleed to see if I squirt DOT4 all over the place…
Love this. Excellent work!
Its going to be immense when finished.
Cannot wait for the next update!
Wowwee! That’s awesome!
I love this thread, fantastic work! 
Amazing skills and willingness to have a go! The brake lines are looking really tidy.
For reference on the switch panel finish - I think you might have bought one of my s2 aluminium radio delete panels from me a couple of years ago? I had these clear anodised and thought it was a very good match to the original chassis colour.
Hijack - are you still doing these?
I only had a few made up I’m afraid, and they’ve long gone.
Happy to share the CAD files if that’s any use to you though?
I’m 49% sure mine is still sat in a box somewhere
Had a couple of weeks of plenty of activity with the car, but no post updates because I couldn’t see any one job through to completion for one reason or another!
Finally hit a couple of milestones today though, so update time.
With the plumbing done I was keen to get some fluid into the system and do a basic bleed, checking for obvious leaks. A “proper” bleed would involve powering up the ABS and running its bleed cycle which I wasn’t ready for yet, but I figured I could at least get some pedal feel and identify any obvious plumbing problems.
I ran a litre of ATE stuff through, twice. This got me on top of most of the air bubbles and achieved me a pretty convincing pedal. In fact the pedal felt awesome, very solid - nice progressive ‘give’ as I increased foot force and really nice pedal height too for rev matching.
I stomped on the pedal a fair few times, made some brum brum noises and played pretend cars for a bit. Once convinced I’d done a fair few “laps”, I clambered out and eagerly inspected all of my new pipes and unions. Happy to report everything was dry as a bone. Will still be something I closely monitoring, but all I can ask is that it passes the first test!
The next big milestone would be to get power to the ABS unit, and see if I could talk to it with the laptop. I had a couple of wiring bits on order, pins, plugs etc to allow me to make a few final modifications to the SCS harness. In the meantime I got on with the switch panels by giving them a lick of paint.
Up next were some decals for them. I picked up a generic sticker sheet from eBay to keep me going. May get something nicer made up in future.
They had no ‘map switch’ button, so turbo it is!
SCS provided the ABS slip decal, and I got a TC one from Lotus for pennies.
Really happy with this ‘sub project’ now that it’s wrapped up. Achieved what I needed, still looks about as OEM as I can get away with and wouldn’t be too difficult to revert if anyone was mad enough to undo all this…
Once my pins and bits arrived, I made a few wiring modifications - just shortening and extending on the SCS harness but also making up a canbus piggyback so I could daisychain the ABS in with the rest of my kit:
Then it was time to get the “interior” out for running the power.
Battery box can just about be removed with the seats in, but it’s a pain and I wanted easy access to the transmission tunnel(ish) anyway for running the wiring.
All I had left to run was:
Battery feed to ABS
Switched Ignition feed to ABS
Yaw Sensor harness, which I’d extended in order to get it smack central under the gear lever:
I took ignition live from the reverse light fuse in the battery box, lobbed the battery lead onto the battery terminal and then eagerly powered the car up.
Nowt. Nada
ABS didn’t make any noise (should it do?!), ABS MIL light didn’t light up and the dashboard didn’t fire up to life with any of the information I’d setup that it should be getting from canbus. Hmm.
I did all the idiot checks, and sure enough found an idiot issue. The MIL light wasn’t plugged in, I must have dislodged it when putting the steering column back together.
With that now lit up, I had confidence the ABS unit was getting power - but still nothing on the dash.
Next step was to grab the laptop, connect my USB2CAN adapter and get the SCS client talking to ABS. That was also a big fail, software just wouldn’t detect it. Hmmm…
ECUMaster make a canbus “sniffer” type application. You don’t set it up to listen for anything, you just connect it and it spews everything it sees onto an interface. I fired this up, and sure enough could see the CAN message IDs that corresponded to the wheelspeeds from ABS - but nothing else. No brake pressure, no slip switch position, no fault codes. Oh, the MIL was on all the time too so it did suggest a fault somewhere on the ABS.
I slept on it, a couple of times I think - then eventually after reinstalling the SCS software a few times I found a warning message suggesting that the client ONLY recognised the proprietary SCS USB2CAN adapter, not third party ones like mine.
Eh well. In for a penny n’ all that.
It arrived quickly, but excited to try it I then found the battery was completely dead. All logical thinking suggested that I’d simply abused it too much having the car live whilst trying to figure out the canbus stuff. All the while with the chargecooler pump trickling away… but despite this, I couldn’t shake off the fear that I’d cocked up some wiring, or the ABS unit was fault - or something and it was causing a draw. The 2-Eleven has absolutely no draw when it’s off, no alarm and no immobiliser - so this was concerning.
Anyway, I grabbed a lifepo4 charger (needed one anyway) and luckily the battery came back to life without any drama.
I hooked up the new USB adapter and got immediate success. Laptop client connected, and we had data!
(most of this is placeholder data that SCS put in for me. Will put proper figures in when I have them).
Not screenshotted is the error/diagnostics page, which pointed out that my yaw sensor and front right wheel speed sensors both had faults.
Turns out neither were plugged in. Fixed that, and the MIL went out.
Now to figure out why my ADU wasn’t showing any CAN data from the ABS. I initially suspected my config, but as the sniffer couldn’t see the relevant channels being broadcast either I suspected something else.
After chatting with a fellow Lotus owner who has the SCS ABS, he asked whether I’d selected the correct CAN profile in the software. This rang a bell from a few months ago when I first played with the software but I didn’t recall seeing the option recently.
Out of interest, I installed an older version of the client on a different PC and found the setting immediately. Seems SCS have made it redundant.
Long story short, the early versions of the ABS supported switchable CAN profiles, with the intention of allowing it to plug and play with various OEMs. SCS have decided to discontinue this, and ship all with the Bosch M4/M5 profile which is becoming somewhat of a standard it seems. In an aid to be helpful, SCS had hardcoded mine to the Lotus S3 ABS profile - so this explained the missing channels.
With all this knowledge, I used the old client to switch mine back to Bosch M4/M5 and everything sprung to life. Well, sort of. I’d cocked some things up but the main stuff was there. Wheel speed, slip switch position… but no brake pressure sensor data from either circuit.
I spent ages cocking about with multi meter etc, as the software wasn’t seeing any brake pressure either. Finally realised that me reaching into the cockpit with my hand and pushing the pedal wasn’t applying enough force to generate enough pressure to register. As soon as I sat in the car and used my foot, it all sprang to life. Doh.
My final drama was when following the SCS documented “first start” list. It instructed to monitor the system voltages for ABS Solenoids, and that they should drop to zero when turning the ABS unit off. Mine did not, it dropped to 1.6V. I wonder if this was my parasitic drain?!
Spoiler alert: It wasn’t, it was a documentation error. SCS confirmed that 1.6V was proper, and they promptly updated the documentation. I’ve since been measuring the battery every night and it hasn’t had any notable drain, nor any draw when measuring between negative terminal and the negative lead - so I guess I did just run it flat.
Pretty dry update, but it does represent a lot of progress. At time of writing other than some small dash tweaks - everything is working as it should. I’ve spent tonight putting the interior back in including a tweak to the driver tillet to raise it up a bit. It does bring my knees a bit close to the steering column, but I was missing a bit of ‘apex visibility’ on track, so will see if this helps.
Next steps are to run the proper laptop-driven brake bleed procedure, do one more leak test and then I guess put the bodywork back on!
This is actually a big update and big step forward! All in all the brake lines and wiring is “almost” first time right. That deserves some respect! Nice work.
Awesome stuff 
mega detail
Some more chunks of progress at the weekend:
Jamie popped round and took the role of laptop jockey whilst doing the ABS bleed procedure.
The procedure was pretty straight forward, I stood near a caliper with a spanner and a hose. The Master Cylinders were under pressure from my pressure bleeder, and Jamie was in the car with the laptop connected and a foot poised over the brake pedal.
Once the sequence started, Jamie just followed the on-screen instructions and I cracked the nipples when instructed to do so. The ABS pump whirred away, and gave me some lovely satisfying streams of bubbles whilst doing it’s thing.
During the start of the process, Jamie needed to press the brake pedal very hard for the software to recognise that he had done so. This correlated with the fact the brake pressure sensors didn’t start registering until you’d applied a considerable force (hence me being unable to do it with my arm leaning into the footwell).
As the process progressed, the sensors detected pressure sooner and sooner - and by the time we got onto the last corner, just breathing on the pedal was registering pressure. Such is the effect of air in the system!
I mentioned before that the pedal feel was lovely even before doing this process, and it very much was. Jamie also commented on it. As we got to the final caliper, Jamie was getting quite excited about how the pedal now felt.
I was eager to try it, so we swapped seats and my golly gosh, the pedal was absolutely fantastic. Unfair to just say it’s “hard”, that’s only part of it. It’s hard, solid but has a lovely progression to it as you pile on the pressure. No spongeyness at all, just a very direct and robust movement. Really excited to see how this translates when actually applying the brakes at speed.
In terms of the brake pressures, pre-bleeding the most I could muster was 50bar per circuit. It was now just a lick over 100bar (1450psi per line!). Sound like massive numbers, but I’ve got no idea what a reference is.
Moving away from brakes, another winter job I had was to inspect the chargecooler pump. I’d noticed the flowrate into the header tank was looking a bit miserable. I’ve commented a few times in this thread that the 2-Eleven IAT’s are a bit higher than the Exige ones were, so investigating this seemed like a sensible route.
When first taking the bodywork off the car back in December I quickly found this. A kink in the pipe where it had been forced around the OE ABS unit a bit.
In addition to this, I had another kink directly at the pump inlet as it bent around the chassis into the sill.
Prior to finding these kinks, I’d fully intended to just stick a more powerful pump on, but now I was less sure of that route. Instead I’ve decided to fix the kinks, and see how we get on. IAT’s are “fine”, so it’s not like this was an urgent task - if I get no improvement from fixing this, I won’t lose sleep over it. It would just be a bonus.
So, fluid out:
With the ABS relocated I could cut the front lines and take about a foot of pipework out, deleting the kinked bit and making for a straighter run:
…and at the pump inlet I swapped the kinked straight pipe out for a preformed 90deg piece to clear the corner of the sill.
Observing the flow rate into a bucket now looks much healthier, but that’s not particularly scientific.
I was now quickly running out of jobs to do before putting the bodywork back on. The NS side panel had remained undisturbed through this work so far, but annoyingly it had the vacuum hose running through it for the MIA brake booster. I did consider just bunging the pipe and leaving it in place, but eventually I stopped being lazy and whipped the side off the car to remove it properly.
I’ll cap this off at the throttlebody.
That brings us up to speed. Later this week I’ll look to get the bodywork back on, or at least enough of it to allow me to get the car outside and do a few basic tests of the brakes.
I am looking forward to your feedback on the brake pedal both on road and track!