2007 Lotus 2-Eleven

Do you mean master cylinder mods?

Obviously I have no first hand knowledge with this, but by trusted accounts the Toyota MC is adequate for stepping up to a 4+2pot setup. The earlier Rover cars however could benefit from a MC upgrade to add the extra capacity.

I’m not sure the servo will influence anything, there’s always the option to throw that in the bin too :no_mouth:

What I’m expecting is a marginally longer pedal, extra fluid capacity in the whole system to move around. Whether that’s a benefit or a detriment I can’t decide.

Yes. I have had 15hours sleep since Thursday night :slight_smile:

Watch this for a cheeky edit …

Donny Update,

The LoT Summer Donny Evening sits alongside Anglesey and Croft in the ‘unmissable’ category for my schedule. Except Croft which I am missing this year, due to a clash with Spa :roll_eyes:

My very first Donny Evening was an absolutely torrential day, cars falling off the track on the sighting laps sort of thing. Ever since, it has been high 20’s or even high 30’s every time we’ve been. It’s a great place to top the tan up and get some laps done.

I never used to be a fan of evening trackdays, felt like poor value for money and were over as quick as they began, but I’m coming around to them. On the right track on the right day, they’re brilliant - you get some intense sessions in and pack up right around the time exhaustion is kicking in anyway.

I was pretty fresh off the back of a full day at Donny (albeit sessioned) last month, so had recent memory of the place and had identified the big areas for improvement. Getting out for the first session was a bit of a rush, had a passenger in waiting, numberplate was still on, trying to undo it next to a roasting hot backbox, etc etc. Ended up going out on balloon tyres and it was a bit sketchy.

I had a problem shifting into fourth when coming down through the gears. It seemed to pass as quickly as it occurred so thought not much of it (until later).

Once I settled down and got all my checks in order, the laps started coming together nicely. After ditching my passengers it was time for my first “1-up” laps of Donny National so I could start optimising a bit.

Only change I’d made since last time was the Tilletts and I’d stiffened my front ARB up. I’d made some handling notes/observations at Blyton and wanted to see what impact the ARB would have on those. The old ‘rule of thumb’ that going stiff at one end improves grip at the other is a bit too generic I find on the Lotus, it has different impact through different phases of the corner - but ultimately the difference between fully soft and fully stiff is still pretty marginal.

I was really enjoying the seats and the new seating position. Need to remember to empty my pockets though because having a phone in my pocket makes a snug fit an uncomfortable one…

Intake Air Temps are usually an area for concern at these hot Donny evenings, last year on the Intercooled car it felt so slow I’m pretty sure an NA car would have walked past it. This year the performance drop was minimal, but still getting high enough IATs to get me into the low 60’s which correlates to 1.5degrees of pulled timing plus the passive impact of the warmer, less dense air coming in for boost.

The evening progressed without much drama, only thing of note being that I sprayed vpower all over the pit garage when opening my jerry can, covering my car, my belongings and the belongings of my garage-mate with it. (Sorry again Jamie). I guess it had pressurised on the trailer and I should have made more effort to keep it in the shade, lesson learned.

The laps trickled on, getting faster and faster, and braver and braver. I came into the evening wanting to improve three areas:

  1. Redgate entry speed
  2. Hollywood/Craners bravery
  3. Abusing the curbs and trusting the compliance of the car more through the final chicane

For #1 I struggled for the first half of the day, then got some passenger laps with Seriously Dave in his 3-Eleven (incredible bit of kit) who gave me a different approach to think about. I think I made a bit of progress after that, but it still feels like a corner I’m over slowing for, but end up losing the rear if I try to carry a single mph more.

For #2 I did OK, I think. But the car can still do more! My GPS minimum speed was only low 90s at Craners last time I came. I need to remind myself that on the stock dials that would probably read as 105 so need to be careful comparing with other people on YT etc, but still it was way too slow.

This week I was over 100mph every time, and as high as 108mph on one particular lap… but I then absolutely filled my pants and pretty much gave up the lap after that :rofl:

This is a comparison from last month, two ‘average’ laps:

I probably gained most by keeping it pinned longer through Hollywood rather than Craners itself.

I suspect my car would be 120+ on a fully flat approach through Craners, whether it can do that or not… I’m really not sure, doubt I’ll ever find out but it’s fun to think about.

#3 was pretty easy to be honest, The curbs on the final chicane are way flatter than I first thought and providing you avoid the little sausage things, you can just turn in and take the rest of it flat, which I did.

As the sun gets lower, our favourite photographer James Roberts Photo - Professional motorsport and automotive photographer gets all arty and we get some pretty cool shots.

I had a small frustration on track, pretty much for the full evening in which traffic was just… annoying. It was not the fault of any individual, but it felt like lap after lap I’d get the whole track to myself for 80% of the way around and then a car would just magically appear at the worst possible time. The pit release system at Donny always feels a bit ‘free for all’ to me, the light stays green all the time and cars are just allowed out onto the track which really compromises entry to Redgate if you’re on a hot one, and then due to the layout you’re likely to be following that car all the way around Craners/Old Hairpin etc before you can get by. When that happens 3-4 laps in a row it gets a bit annoying.

It was just unlucky though, as LoT numbers were characteristically low. The track was far from crowded.

The day ended 2 mins early with a redflag, I was cursing because once again I was on “a good one” and something happened to spoil it. As it happens, it was a good friend sat beached in the gravel so I did feel a bit bad, for about 5 seconds before the mockery began.

Trundled into the pits to call the day a success, had a natter, took some photos and started packing up.

When I came to move the car, I had a very floppy gearstick. No resistance at all, and certainly not selecting any gears. Uh oh…!

A quick inspection suggested that the linkage on top of the gearbox had fallen apart, so hopefully it’s nothing fatal to the box and hopefully is an easy fix. It’s an aftermarket linkage (LETSLA) so there’s a chance a bolt has backed out of it or something. Need to get familiar with how they bolt together so hopefully it can be easily put right.

Amazing that it survived the track and chose it’s moment to just flop apart as I pulled into the pits… BUT that’s my third day-stopping issue after 3 hours of track time this year so far.

ECU shenanigans at Blyton, brake discs at the second Blyton, and this issue at Donny.

Not a success rate I’m proud of, needs to improve.

Pushed into the trailer (thanks boys) and homeward bound, via KFC.

Couple of video clips, almost the same and nothing particularly interesting or dramatic:

2 Clearest laps from penultimate session: (1) Lotus 2-Eleven at Donington Park - YouTube

2 Clearest laps from final session: (1) Lotus 2-Eleven at Donington Park - YouTube

Only notable change between these sessions is that I started short shifting into fifth on the Schwantz(?) Straight/Curve thing. For earlier sessions I was hitting the limiter here in fourth and using that as my cue to gently lift off for McLeans. In fifth I found I could actually keep it pinned around the whole curve and then slam on for McLeans. This was gaining my huge laptime gains, BUT I could never carry it through a full lap, as I always hit traffic shortly after.

End result from retrospective video/log review is that I gained 3 secs from last month, but my virtual best lap if adding together all my best sectors could have netted me an extra 2.

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If you were timing your laps on a track day I would suggest that you are making leaps and bounds now.

I really must start to log data to be as productive as you.

I do enjoy your write-ups. Technical and informative.

Some of those images are superb!

This one being a fav :

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I am cautious that datalogging and laptiming is all sort of smushed into one, and I am pretty annoyed when people blatantly post/talk about timing their trackdays in public (it will hurt us all if the TDO’s/Circuits end up having to pay massive liability insurance bills) so that does make me a bit of a hypocrit, but I’ve had a few TDO’s tell me now that logging data is ‘fine’, as long as it isn’t used actively during the day to effectively egg you on and push your limits too far.

90% of what I want out of logs is nerdy things like what is my fuelling doing, did my TC intervene when I thought it did, is the air intake getting too hot, etc etc. The fact that I can also compare minimum corner speeds between trackdays and stuff like that is a nice bonus.

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This is exactly where I want to be too.

If I were a racedriver ( I just think I am ) I would have live telemetry fed back, but alas I just want to work out where I was fast, where I was slow and ultimately work out what style suits the fastest laps.

I too am a data geek. These kind of things are awesome to look at and analyse. Even if I don’t understand it all!

I would love a AIM dash to have some readouts like you. One day …

Speaking of which… IATs.

I’m having some thoughts about changing my supercharger pulley again.

As a reminder, I have a 2.9" pulley fitted which is enough to produce 301bhp/202ftlbs when the DBW is fully open at 161kpa.

Above 40degrees IAT I start trimming timing, so ultimately that 301bhp starts degrading.

90% of the time, in fact probably 95% of the time I’m in my “road” map which has the DBW pegged at 65%. This produces 281bhp/193ftlbs on the Dyno and total boost is in the region of 150kpa.

As I’m trimming power using DBW, the SC is still spinning just as fast in either map, and still generating the same heat even if boost output is lower in one of the maps. I’m basically carrying an IAT penalty all of the time, when only using fully unleashed power for small stints on the road and rarely/never on track in fear of expiring the gearbox.

One scenario is that I get Spa done and dusted, Spa has been the source of my anxiety as I really didn’t want to smash a gearbox on the run up to that and compromise the big/expensive trackday in the centre of my schedule. Once Spa is done, perhaps I run 300bhp more often as I’m less concerned with a bit of downtime whilst finding/swapping gearboxes. I’m less annoyed about carrying the IAT penalty if I’m actually getting to play with all of my toys.

Other scenario is that I get rid of the 2.9" pulley and go for a 3.0" pulley instead. According to unverified sources this will lower my total boost potential by about 7kpa which will land my total power output somewhere in the region of 280-290bhp but will reduce my IATs by a amount.

If this means that I can get the same 280bhp but consistently, all the time - then it’s probably a better way for me to go. Lower temps means everything is just happier. I could still have switchable maps if I really wanted to, and maybe look at a 260(OEM) and a 280(Race) map for instance.

I know from my Exige that going from OEM (3.4ish) pulley to a 2.9 was a significant hit to IATs. With the same Chargecooler setup my temps went from “barely above ambient” to the 50s and 60’s that I’m seeing now, so not sure exactly where I’ll end up by dropping just 0.1" but we’ll see.

The other option of course is to find a way to optimise chargecooling. An extra auxiliary precharge rad? Not sure, but I think options are limited.

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Or go to a TVS charger with chargecooler and peg everything back to make similar power without the sky high IATs?

Yep that would probably be the ‘best’ solution, just a few more $$ than sticking a different pulley on.

TVS feels like one of those 2ZZ upgrades I’ve been flirting with for years.

Witnessed from inside of T1 a few times and it looked wrong. The guy in the olive green Exige was released and then immediately swamped with cars. Great writeup, missed the shot of you washing your shoes tho - that’s the content we’re all here for :wink:

Without wanting to drift the thread, James is bloody good. Jumps in the car, gets tons of angles and shots that you’d not see yourself. I know it’s his job and all but then his processing is fast, and I’ve been using Photoshop for… oooh [counts on fingers] most of my life.

Anyway, just held the camera up to the Jag parked near us and this is straight out the box - next time we should get stood on top of Mark’s van and take some decent shots in the paddock.

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Fonzey have you thought about mounting an aquamist or aem system to lower Iat temperatures, the same thing happens to me and I would most likely mount this system and with the ecumaster we would do a combination

Loving it :+1:

Same seat in elmo. Made my own mounts as Im a beanpole and got it 2mm of the floor pan. Its a very good seat indeed.

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Yep there are things that could be done to boost the chargecooler, but I’m not sure it’s something I want to chase. The SC is spinning right on the limit of its capabilities, I could add some auxiliary cooling and use the ECU to trigger it but ultimately if I slow the SC down a bit, it will probably thank me for it.

Following Donington I didn’t even take the car out of the trailer, and a few days later I took it to see Dave and John @seriouslylotus .

We had been discussing for some weeks (and to be honest, on and off for years over the span of my S2 ownership career) a brake upgrade. I’ve repeatedly stated in this thread that the braking on the 2-Eleven is mega, should be illegal, etc etc - so the thought of ripping the system out and making big changes made me very nervous - but it’s something I’ve wanted to try for years. Cracking that disc at Blyton was just the catalyst to finally tip me over.

Nothing that follows was logical or sensible, I should really have just lobbed another set of discs on, carried a spare pair and got on with life - but sometimes you just need to scratch an itch.

First though, the gear linkage needed fixing. Whilst rolling into the pitbox for the final Donny session it just fell apart and I was left with no gear selection to get it back on the trailer. Luckily the fix was identified in seconds in Dave’s yard, a bolt had just backed out that holds the two halves of the linkage together.

It was an aftermarket linkage fitted as far as I know about a decade ago, we correctly suspected a missing spacer so with some best guessing from some old photos - Dave knocked up another on the lathe and we were back up and running.

Right, back to brakes.

From the factory Lotus fitted 288mm discs all round, with AP 2 pot calipers up front and brembo sliders at the rear. The cars are typically biased heavily towards the front as a way to make the car benign, and the standard braking system DOES work very well, despite looking a little feeble.

Some later cars came with some AP 4 pots at the front, but no changes (that I’m aware of) were ever made to the rears from factory. This tipped the bias further forward and in the eyes of some, became a backwards step.

There are a bunch of options for addressing this, but Dave and John have tried them all - and I punted the car to them to let them put on their interpretation of the best setup. I had limited time before Spa, and some other stuff going on which meant I just wouldn’t have the time to do the spannering myself on this occasion. (So thanks Dave for all the photos for the thread).

What we ended up going for was the following:

  • AP 4 Pots for the front
  • Move AP 2 pots to the rear, and add a standalone handbrake caliper
  • 308mm AP discs all round, floating on SL’s own bells

Moving the 2 Pots to the rear is the most exciting bit to me, it puts a proper caliper on the back and will move the brake bias slightly more rearward. Obviously it’s still biased to the front, just less so compared to standard setup.

I’d previously viewed the OE braking setup as tyre limited on the 2-Eleven as I could lock up or at least trigger ABS regularly, but looking at it a different way - it locked up because so much brake force was focussed into one axle. By spreading the load a bit, I hope to have a bit more stopping power before the tyres give up.

AP Discs were selected over Alcon due to their PCD, meaning that the swept area is a much closer match to the pad profile we’d be using, avoiding that un-worn rusty band around the centre of the disc.

I got a nice running commentary of the work via photos from Dave.

As the AP 4 Pots use banjo fittings, it would mean swapping brake hoses too. On some S2’s this means front clam off, but the 2-Eleven allows you just enough access to do it… though my chargecooler plumbing really didn’t help.

The handbrake caliper was the missing piece of the puzzle before. SL imported these from the US with the Lotus specific modification for plug and play fitment but the US company have since discontinued them. Luckily another Lotus community member stepped up and bailed me out by selling me a pair they had sat in a box ready for a possible future project. Thanks again Sean!

Adding bigger discs, an extra caliper and bigger calipers at the front had me convinced I’d be pilign on unsprung weight which was a real shame, but I was pleasantly surprised when all the bits got weighed.

The bigger 308mm discs with all hardware were 1kg lighter PER CORNER! This is a huge amount of rotational mass.

The AP 2 Pot gained a bit of weight through the extra bracketry needed to mount it on the rear:

But the original Brembo sliders are absolute boat anchors, so binning those off claimed a fair chunk back too.

All in, the whole setup is lighter by around a kilo or so. Very impressed.

With the 2-pots off, Dave modified them for me to swap them to a banjo fitting to match the new fronts:

This isn’t really mandatory for the conversion, but it will make bleeding a lot easier in future as there is now a bleed nipple in both sides of the caliper. They would previously trap air above the brake line inlet.

The fancy new 4 pots use the original mounting points, as they’re Lotus specific items (I think??):

As said before, the discs were carefully selected for the swept area to be a good match for the pads.

Handbrake mech uses original cable:

Worst spoke positioning ever for brake photos: (I take the blame for those)


For Pads I wanted to stick to Carbotech XP8 that I used before on the old setup, because I wanted a good back to back test… but I left it a bit late to get organised and couldn’t sort any in time for the new 4 pots. As a result, I’ve ended up with Performance Friction in there, 08s I think(?).

I know they’re a dusty pad, but the Carbotech weren’t particularly clean either.

On collection day I went for a quick test drive around the block. Initial impressions are that the pedal feel is very different, I had quite a stiff/solid pedal before but now the pedal travel is a little ‘freer’ which initially feels like poorly bled brakes.

Once moving though it was soon apparent that despite the pedal providing less resistance, the braking force was immense. It’s always difficult to judge brakes on cold/dirty tyres on the road but there is no question that the stopping power of the car has increased dramatically.

It has increased so much that I’m actually a little bit scared of it. The brakes will lock up with ease on the road and a foot recalibration is required. I’m sure I’ll get the hang of it, and use the brake pedal less like i’m trying to push it through the bulkhead and more like I’m modulating a precision instrument.

The big test will be on track, with hot tyres to see just how much the new setup can be abused. My hope is that any/all heat management concerns are now behind me - and these should be up to the job of whatever duty cycle I throw at them. I’m expecting a backwards step in my ability to maximise braking on track, until I relearn them - but my hope is that the new pedal feel will gain me in modulation what I’ve lost in “stiffness”. I’ve been pushing further and further into corners with my idiots approach to trailbraking so after taking a couple of steps back perhaps it will aid me in that area too.

I’ll be honest, the difference in braking force is so stark that I am concerned that I’ve gone too far - but I’m sure by session #2 at Spa all that will be behind me. If not, well they look cooler.

Thanks again to Dave and John for the workshop time, few little tasks with a job like this would have caused me to drag it out for weeks (little machining jobs etc) so having their assistance here was critical to get it done for Spa. I do wish I did it a bit sooner so I could trial it on a UK track first, but hey ho.

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Probably also worth noting that I got an odd feeling of ‘doneness’ after the brake job was finished. I had a roadmap planned for this car, much of it repeated from my Exige, some of it new stuff - but I’m pretty much ‘done’.

Don’t worry, that doesn’t mean I’m bored and it will be for sale any time soon - but it may represent a change in pace for the thread. It will still be a heavily used track car, so stuff will break and wear out, but the big flashy purchases (thankfully) are now done.

I’m still expecting a gearbox expense at some point, and might tidy some bodywork up depending on how I’m feeling/how many cones I hit, but hopefully I’ll just be tweaking, optimising and maintaining the car now rather than throwing fancy bits at it.

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Ill just leave this here

Gearbox upgrade
TVS1320

Love the update. Will be following the braking with interest and 100% not on my list of upgrades at all. Ever.

When is Spa?

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Get on the boat on Friday, trackday on the Monday

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Yeah, let’s be realistic the box will probably want doing eventually. In terms of SC I’m leaning further towards just slowing it down a bit with a 3.0 pulley and enjoying whatever it produces.

You have changed …

( however I fully understand )