2007 Lotus 2-Eleven

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MTW

448 posts

41 months

Thursday 15th June 2023
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Great write up!

TheJimi

25,021 posts

244 months

Thursday 15th June 2023
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Love that car, as always, and I'm enjoying your introspections and thought processes smile


Rodd Nock

2,068 posts

262 months

Thursday 15th June 2023
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Your logic on s/c pulley sizes seems perfectly sound to me. Given that a pulley will be quite cheap, and you can do your own on-road mapping to re-calibrate DBW percentage and maintain existing boost pressure, I think you should JFDI and report back with IAT results biggrin. You can always revert back to the current setup if losses outweigh the gains!

Fonzey

Original Poster:

2,066 posts

128 months

Thursday 15th June 2023
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Thanks everyone. I know some of this stuff is a bit dry but I write it mainly for myself biggrin

Rodd Nock said:
Your logic on s/c pulley sizes seems perfectly sound to me. Given that a pulley will be quite cheap, and you can do your own on-road mapping to re-calibrate DBW percentage and maintain existing boost pressure, I think you should JFDI and report back with IAT results biggrin. You can always revert back to the current setup if losses outweigh the gains!
Yep that's my thought process. Lob bigger pulley on for minimal effort/expense, and then just fine-tune DBW to match current boost levels. I know I've got a map that is appropriate for anything between 140-160kpa so anything I hit on that range should "just work". My ignition advance could probably be increased a bit if I do drop maximum boost which should close the gap even further whilst keeping IAT down.

Question is, do I do if before Spa or do I have my fun at Spa and go mental in the final hour on full power. If it blows up, meh... I'll have had my fun and will have a couple of months downtime before next TD.

GiantCardboardPlato

4,247 posts

22 months

Friday 16th June 2023
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Fonzey said:
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 <yet to be tested> amount.
What the pressure thatn the supercharger generates with each pulley? It’s easy enough to calculate/estimate the temperature increase for a given pressure increase.

Fonzey

Original Poster:

2,066 posts

128 months

Friday 16th June 2023
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GiantCardboardPlato said:
What the pressure thatn the supercharger generates with each pulley? It’s easy enough to calculate/estimate the temperature increase for a given pressure increase.
It's in the region of 1psi (7kpa) gained per 0.1" dropped. I'm not sure if it factors in, but it's well documented that the MP62 is already right on the edge of its efficiency window with the Lotus OE pulley so going smaller as I have is into diminishing returns.

Fonzey

Original Poster:

2,066 posts

128 months

Monday 26th June 2023
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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 piling 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.



Fonzey

Original Poster:

2,066 posts

128 months

Monday 26th June 2023
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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.

mattdavies

254 posts

158 months

Monday 26th June 2023
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I enjoy this thread for the regular updates so please dont stop updating us with maintenance and Track day de-briefs.

On the Brakes, I recently went from big caliper front to big caliper all round and the braking experiance was so different. instead of the whole car pitching forwards while scrubbing speed the car stays fairly level and speed just disappears in a much nicer way.

GiantCardboardPlato

4,247 posts

22 months

Monday 26th June 2023
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Love this thread.
Would you recommend SL and do they do insurance repairs? (would they have somewhere to get body/paint work done?).

Fonzey

Original Poster:

2,066 posts

128 months

Monday 26th June 2023
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mattdavies said:
I enjoy this thread for the regular updates so please dont stop updating us with maintenance and Track day de-briefs.

On the Brakes, I recently went from big caliper front to big caliper all round and the braking experiance was so different. instead of the whole car pitching forwards while scrubbing speed the car stays fairly level and speed just disappears in a much nicer way.
Oh yes the thread won't be going anywhere, just if anyone only tunes in only to see the money fountain spraying upgrades at the car... I want to temper expectations biglaugh (Though I may have another thread for that to come...)

Thanks for your comments on the brake setup, I do look forward to getting to grips with them. In theory they should be a really strong upgrade but it's hard to imagine it when this area of the car was already so bloody potent.

shalmaneser

5,936 posts

196 months

Monday 26th June 2023
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Do you know the f/r bias before and after? Have you fitted a valve to tinker with this?

Feeling a lot more grabby is a good thing I think, when I go from the hatch to the Porsche it always feels like the brakes are rubbish but you recalibrate your foot pretty quickly each way.

I've always been interested that in the car world performance cars tend to have heavier brake pedals than normal models. It's the other way round in the cycling world.

Fonzey

Original Poster:

2,066 posts

128 months

Monday 26th June 2023
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shalmaneser said:
Do you know the f/r bias before and after? Have you fitted a valve to tinker with this?

Feeling a lot more grabby is a good thing I think, when I go from the hatch to the Porsche it always feels like the brakes are rubbish but you recalibrate your foot pretty quickly each way.

I've always been interested that in the car world performance cars tend to have heavier brake pedals than normal models. It's the other way round in the cycling world.
No I don't off the top of my head, but some clever sod did the calcs years ago and it exists somewhere on a forum which I read a few weeks/months ago and can't find now.

It was something in the region of:

2Pot F and Slider R = 65/35
4 Pot F and Slider R = 70/30
4 Pot F and 2 Pot Rear = 60/40

Or something along those lines.

GiantCardboardPlato

4,247 posts

22 months

Monday 26th June 2023
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shalmaneser said:
Do you know the f/r bias before and after? Have you fitted a valve to tinker with this?

Feeling a lot more grabby is a good thing I think, when I go from the hatch to the Porsche it always feels like the brakes are rubbish but you recalibrate your foot pretty quickly each way.

I've always been interested that in the car world performance cars tend to have heavier brake pedals than normal models. It's the other way round in the cycling world.
maybe its because in a car, heavy braking increases the pressure on the brake pedal anyway, when that's not a factor on a bicycle. the firm pedal helps you apply consistent pressure as the longitudinal g-load varies.

Fonzey

Original Poster:

2,066 posts

128 months

Tuesday 27th June 2023
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Got the car on my lift to do a few pre-Spa checks and tidyups. Allowed me to get some decent brake photos too.





Treated the 4pots to some ceramic coating from Gyeon. Vain attempt to keep the Performance Friction dust away for a while.



I also fitted a spare splitter that I've been working on for a while.



It was the second of the two I cut out of marine ply over winter, and my objective for this one was to make it look slightly less like furniture once painted. I made it a bit better, but it still looks like an Ikea desk.

The old one had taken a knock when loading into trailer, and I found the ply had also started delaminating at the trailing edge (so you couldn't see it when mounted) and the top layer of ply was starting to rise in certain areas. I didn't take much care to treat the first one, just sanded it and painted it.

This second one got a few coats of shellac(?) sanding sealer first, so hopefully that adds some longevity. It took me ages over several days to get it looking half decent, and I'm still not that happy with it. I think if I do another with ply I might try coating it in some sort of epoxy resin first.

Other options include trying some alternate material. I hear about some signmaking stuff which is like an aluminium composite sandwich, but I don't know how sandable that is... which means my Jigsawing would need to be absolutely on point... which it wouldn't be.

Happy to take suggestions onboard for this. It will likely be a winter tidy up job now.

MTW

448 posts

41 months

Tuesday 27th June 2023
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Great work! Nothing better than a good set of big boy brakes!

Fonzey

Original Poster:

2,066 posts

128 months

Sunday 9th July 2023
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Half Spa Update, half travel blog - so apologies in advance! If you want actual 2-Eleven content, just skip this and wait for the next update.

Day 1&2:

Lotus on Track had landed on well with the timing for the Summer Spa trackday by bagging the Monday following the GT Enduro 24h event. We used this as an opportunity to get the boat on the Friday night, and have a few days to enjoy the festivities before our track time.

For once, as a Yorkshireman it felt like I had the long straw and the easiest travel arrangements. Catching the ferry from Hull meant a small 45min hop and I'd be in the bar before the trip had really begun. We did however use it as an opportunity to have a pre-boat meet at Seriously Lotus, as Dave and John are conveniently located a few mins from the dock.



In our small convoy would be:

Simon in his Elise Cup 260
Jamie in his Exige S (my old car)
Darren in his 911
Chris with his Honda converted, and recently restored S1 Elise
and me, in a Volvo.

We had a passenger amongst us in the form of Jaik, who despite a colossal effort was unable to finish his long term Elise project in time.

After some hospitality and words of wisdom from John and Dave (and a footwell full of spare brake pads, just in case), we were on our way.

Between us we'd had a fair few sleepless nights about the new carnet requirements since Brexit, particularly us with trailers. But as soon as we mentioned the cars were road registered and insured, they really didn't care - in fact my trailer never even got inspected. I could have had three generations in the back for all customs' cared.





Volvo was particularly well loaded for this weekend, trailer had an extra set of wheels and tyres in for Jamie and I was also lugging around 100kg worth of Gazebo and sandbags to ballast it. Funny story about that, later.

On the boat we met the rest of our party for the weekend, Shaun in his new-to-him S3 Elise and Rich trailering his Komotec fettled V6 Exige.

No boat pics, average food, terrible entertainment, acceptable beer. Onwards!

The following morning we had grim weather for our 3-3.5hour trek towards Spa. We took our time, got split up, usual road trip stuff.

Consumed diesel


Enjoyed some top notch service station dining as you tend to do in Europe


Finally we arrived at our Gite just a few KM from Spa. This was recommended on the basis of good trailer parking, but honestly - that didn't really materialise. To get the two trailers parked we had to unhitch them and manhandle them into a corner, but wasn't too bad.



Had we have turned up with 3 or 4 trailers as was the original plan, it would have been a bit of a problem tbh.

After a quick turnaround, we jumped in the two tow cars and headed over for the start of the 24h race, which we missed by about 10mins. Oh well, it was a good hike anyway.



I've been lucky enough to visit Spa for two Grand Prix events, and now this - and Eau Rouge never fails to take a breath when you approach from the main entrance.



I've done a few GT events before, but never a 24h and I was well impressed at the turnout. Spa is a monster of a circuit, and I imagine the fans were all compressed into the paddock/Eau Rouge area but still - there were loads and loads of people there. Great to see.

For a few quid extra we'd upgraded our tickets to paddock passes, which was well worth it - loads to see and do, and we found a great spot (for yet another few quid) on a rooftop bar above the pits.







Eyeing up a new tow rig...



Some fancy stuff being unveiled/on show.





As light started to fade, we grabbed pizza and made our way to the Eau Rouge grandstand to get some shots of the lights coming on. Did not disappoint!









We probably left around midnight, the circuit showing no signs of slowing down and seemed to be more people there than ever enjoying the 'music' or whatever tf it was the DJ guy was blaring out.



Back to the Gite for a decent nights sleep, then onto the next day. Oh, and no idea what was happening during the race.

Day 2/3 to follow.

Feirny

2,528 posts

148 months

Sunday 9th July 2023
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That last image especially, is class.

Fonzey

Original Poster:

2,066 posts

128 months

Tuesday 11th July 2023
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Day 3.

Plan for Sunday was to go back to the circuit and watch the 24h race wrap up, but a throwaway suggestion at breakfast meant we decided to go to the 'Ring instead.

Doing a lap didn't appeal to many, especially those of us with trailers. Weather forecast was variable, and getting the 2-Eleven 90mins into Germany just felt like a chew tbh.

After a short discussion we decided that the 911, the Elise Cup and the Volvo would go. An Exige, Audi and the two trailers would stay at the Gite.

I'd never done the Nürburgring before, it doesn't appeal as a trackday venue but I had heard great things about the sights and sounds, so was looking forward to it.

It didn't disappoint, strong representation from the UK but some cracking cars from across the continent too.





The whole day seemed to desensitise us to the 'special' car. Non RS GT3s started to look dull, it was bonkers.

All three cars decided to buy a lap, so we could all experience it one way or another. But that required a bit of track prep for the Volvo.



We had been lugging around the massive gazebo I bought, so we buddied up with some fellow Brits camped out with a trailer and dumped our stuff with them. Giddy to go, we then got notification that the track was closed due to an incident and would be reopened in 45mins or so.

As it happened, 45mins turned into several hours, as we later found a UK plated BMW had gone off the track in a pretty bad way. I've not heard anything since, but fingers crossed everyone got out with the least possible damage.

The various parking zones provided constant reminders of how quickly it can go wrong here



With time to kill, we did several laps of the carparks and I did a bit of studying:


We had a bit of a deadline, as we were due to move from the Gite into the Hotel right next to Spa for the duration of our stay, and we had dinner reservations etc. Just before calling it quits and heading back to Belgium, the horns blew and the track went green.



(The helmets were a bit of fun. Really could have done without mine on tbh, made visibility a bit dicey whilst dodging the constant GT3 missile attacks from behind!)

Off we went...





We all thought we were hilarious lapping round 4 up in a diesel Volvo, but I imagine it happens 40 times a day. Hey ho, we had a laugh.

The car was.... entertaining. Nobody was expecting it to be quick but the complete lack of consistency is what really bites you when you're used to driving cars engineered for performance. Sometimes the brakes hauled us up well, sometimes it was like they didn't exist. Gearbox wouldn't downshift unless I was in a precise 750rpm band, so any degree of engine braking was pretty much lost. Luckily it didn't have the grunt to get us into any real trouble.

My main concern was blocking the laps of somebody actually taking their day seriously, so with the help of my rear benchers we were sure to dive out of the way at the earliest sign of anything coming through. I think we did OK.





We had a small discussion in the cockpit coming up to the Karussell about whether to go for it or not. The entry is STEEP! No video or photo can do that justice, but I lobbed it in and we had a go around.





All in all it was a fun lap. When we got to the yellow flagged areas where barrier repairs were still ongoing, we got a feel for just how bad the earlier BMW crash was. It was long gone into the trees, and evidence of a fairly robust forest fire too frown

The 911 and Elise Cup 260 also went around, the tight arses didn't buy any photos though and I refuse to post watermarked ones. They both had fun, Simon in the Elise perhaps a little more than any of us.

After a quick debrief with our storage buddies for the day, it was time to head back to Belgium and switch accommodation.



Via this sign, obviously.





Our hotel for the remainder would be the Hotel de la Source, right at the entrance to Spa. We couldn't get into this for the first night due to the 24h, but it felt good to be in walking distance of everything we'd need for the duration.







I wish I knew who won the 24h, because just after checkin I jumped in the lift to find a very small, athletic and chuffed fella holding a trophy almost 3/4 his size! I had my race boots on, so gave him that knowing nod and wink. Well done lad.





honda_exige

6,040 posts

207 months

Tuesday 11th July 2023
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Great report!

I'm out there in August, Spa trackday on a Wednesday then Nurburgring Trackday on the Friday, come back for a week then back out for weekend TF cloud9