you keep that sexy rear end away from my eyes.
Back in the paint booth today. Ideally the front splitter wants smoothing out but for now it will do
In tonights episode of that will only take 5 minutes but takes an hour : Idle control
I whipped out the laptop, connected the USB and lowered the target idle. It wouldnt go below 1350ish RPM.
That means one thing - I have the idle stop screw too high. Break out the 8mm , loosen the nut and wind down the screw a tiny bit.
Get in, target rpm met.
< metallic noise meeting another metallic object sound >
No problems to report though so shut off the engine and powered down the laptop.
Ill just tighten up the 8mm argh. Its in the bay somewhere.
Cue taking the undertrays off to find a bloody nut. That was fun.
Impact driver does most heavy lifting
Undo everything
Wack the undertray as its held down to reveal the nut
Fitting is reversal of the undoing.
Its ready for map tweaking now.
Could be worse.
Where the hell has that nut gone? Sod it, map tweaking time! What the hell is that noise/loss of power?
Ahhh,found it! 
Map tweak booked in for 15 MAY 23 @ 1000
Its going to end up as one of three things
- More power
- Destroyed gearbox
- No power increase
Actively looking for a quaife sequential and gearbox control unit âŚ
I have changed over my pads today. They were getting a bit thin and the trackday in a few months motivated me to do so.
No drama and the first time the lotus hasnât fought me!
25-30 stops apparently at 50% force to bed then in.
What have you gone for? I recently tried CL RC5+ and was genuinely quite happy with them, but they didnât seem too happy by the end of a day at Donington, so Iâm fitting CL RC6 now! Very excited to see how they go!
DS1.11
I have used them for 20k miles on track and they are great tbh. Everything I want from a pad.
I can confirm that bedding in a set of pads on the way to mapping isnt the correct way to do things. Especially if you leave early and dislike morning so forget to bed them in until you spy a tractor.
They are now bedded in.
The drive over to Leeds was dull and slow partly due to 2 year roadworks where they were working on approximatly 16cm of road at a time.
âHowever, I still got there. Car was loaded onto the dyno and some pageup/pagedown occured. Some timing was taken out and some added in.
This hasnt resulted in a dead gearbox just yet, but we did make more power
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Nice results, are you happy with that?**
** Is the gearbox still alive?
Awesome results!!! Really excited about sticking my BWR throttle body on now too! 
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Yeah, a gain is a gain mate.
Desperately need to investigate my pulley size mind
Box has done about 75mi today so itâs all good*
- for now
Good stuff Andy.
I am curious if there were any experiments done in directing airflow under the car where the exhaust peeks out with a diverter or anything.
I cant seem to find anyone who makes one or any evidence of any experiments.
Poke the backbox out of the back is the general recommendation/approach I think.
The floor exit is just compromised if youâre chasing aero.
Yeah, thats what I read but I dont like the asthetics of that ( unless its the linked image )
Curious if anyone went full send like a deflector
Did I upload this yet?
Racecar Engineering- Lotus Exige Aerodynamics.pdf (3.9 MB)
The section on diffuser design touches on this a bit. Though not tested, a mitigation is proposed of:
âwhile mitigating modifications might involve isolating the tailpipe(s) with additional vertical fences, or with a moulded streamline fairingâ
Unmodified, the standard floor exit exhaust seemed to detach the flow of the diffuser along the full middle element of the diffuser, so by putting the exhaust into itâs own miniature element would in theory isolate that.
The outboard elements are similarly useless due to the detached airflow caused by the suspension apertures which the previously discussed difflow plates attempt to address in addition to massively extending the outer strakes both towards the ground and as far forwards as possible.
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This is gold.
I was considering a 5 element diffuser and now I am convinced its the right thing to do.
I might also consider a dome cap type deflector that goes over part of the exhaust to mitigate the distruption there.
While I applaud Reverie, Simon McBeath and MIRA for getting an Exige in a wind tunnel, there are a few caveats. Iâd get a mate to explain this, but his explanations make my head hurt. Alot! He works for an F1 team in the aero dept, designing the 2/3 rds scale models for their tunnel.
To put in into more normal English - as I understand it from him! - there are a number of issues with the MIRA tunnel compared to reality and the Exige platform. Donât get me wrong, we have considered putting the orange car into MIRAâs tunnel, and we still are tempted, as itâs about as good as is available for most people.
The MIRA tunnel has no moving floor. So boundary layers, relative airspeed vs height from floor and something else he said that was ridiculously complicated, made the results a good static indication, but not that real world.
The exhaust in the diffuser is not ideal. Maybe. But at what engine/vehicle speed? Engine off, and bad, then yes itâs bad, but thatâs only when youâre parked, so not really that bad. If at 8500 rpm, full load and x vehicle speed, and itâs still bad, then itâs bad, but wasnât tested, as far as I can see. If the same as above, and itâs really good, then itâs also really, really bad, as changing engine load could make things really exciting! Followed by a bit crashy.
The biggest issue is ride height, rake, pitch, roll and dive. To control all five, and some others, needs a huge compromise on set up, none of which is nice on a car that is used in âsub optimal conditionsâ
And no, I canât get him to put an Exige in their tunnel! The last time they ran the tunnel flat out - about 118 mph from what I remember, bearing in mind scale sized cars now - everyone in the building, left the building as it was shaking so much. And the local grid told them not to do it again. As all the lightâs in the area went a bit dim.
Thereâs lots of bitâs that can be made betterer, but sadly an Exige is never going to be a true aero car.
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PS Wait until I show you the underside of the orange car! This was only ever done to reduce drag to achieve one thing, but havenât tried it yet. The downside is you need to drill some small holes in the chassis, so a bit one way.