What a superb write up! Great result as well for your first event!
What were your AR1 thoughts compared to the ZZR?
Cheers Andy 
It’s unfair to judge the comparison under sprint conditions but they came in really, really quickly. My corner speeds on the faster stuff is about as well as I’ve ever done there, and usually I have the benefit of the tyres being hot and sticky.
I also couldn’t gauge how well they lasted during a session, as that was a other ZZR strong point.
Cadwell would be a great gauge of their performance 
I shall be following the AR1 saga with interest. I can hear my 52’s wearing out in the garage …
Well done to you, sir! A fab achievement! I’m also very curious to see how your tyres fare at Cadwell… Have you ever tried A052 to compare them to?
Thanks Matt!
Day #2, onto Cadwell.
Getting the trailer hitched up on a morning was now the work of a moment, so I was soon on my way - but seriously tired.
Stopped for coffee to sort myself out, so arrived at track a little late… missed the sighting laps in fact. Martin @ LoT was a champ for getting me signed on, and missing some track time wasn’t too concerning as I had both the day AND the evening booked! Crikey.
It was a sessioned day, split with MSVT Cars and for my first time ever… sharing with MSVT Bikes! So quite a mixed paddock. The evening was to be LoT exclusive OPL so I was looking forward to that after a chilled day, probably missing every other session to nap…
Our session soon came back around, so I went out with the intention of trying to find out how much these Nankangs would pressure up, so nice and steady with a slow build up. I let all other cars past and settled into a groove. A lap or so later I was catching traffic, overtook a couple of cars and then had some clear track in front of me to attempt a decent lap.
I entered the mountain in third, slight lift as I crested and then came back onto the power for a quick squirt towards the trees. I’m not sure if there was a bang, crunch or what - but suddenly the revs flared and I was bouncing into the limiter. Uhoh, no drive.
Shifted up to fourth, nothing. Down to second, we had drive - so limped around to the main straight to try 4th, 5th and 6th. Nothing at all. Oh dear 
I shuffled round a full lap in second and then got to the pits. Reverse, 1st and 2nd all worked fine. Beyond that, nothing. I could select fine, the linkage was moving appropriately on top of the box and when letting the clutch out in the missing gears, you can feel the slightest bit of engagement and then just a grinding noise.
It’s as if it’s stripped the teeth off of four gears simultaneously, which clearly isn’t possible. Final Drive must be intact, otherwise R/1/2 wouldn’t work… I’m stumped. seriouslylotus was in attendance at Cadwell as support/parts supply so John and Dave helped me rule out anything stupid - but we could only conclude it’s internal to the box.
Any long time readers will know I’ve spent a lot of time, effort and money on protecting this gearbox. Every feasible upgrade has been done - there’s nothing else I can do to make this box stronger, to my knowledge… so this sucks. Big time.
I’ve been aware of the C64 gearbox issues since day 1, in fact I think I reference it in my first ever post of this thread - so I’ve been flirting with danger for a while now, but I thought I’d done enough… I really did.
I’ve spoken to a few specialists, and nobody has heard of these failure symptoms before. The only theory we can come up with is a snapped shaft… probably input, maybe output - I don’t know enough about the internals of the C64 to say what’s feasible.
My previous rebuilder has stepped up, he’s willing to drop everything and get my box stripped as soon as I can get it off the car. He’s really curious, he’s never heard of a failure like this.
So that’s it, sorry for the build up - but Day #2 of my motorsport weekend was all over by 10am. I know almost nothing about the Nankangs, who knows when I’ll next get to find out.
I need to start thinking about what’s next. I have to assume the gearbox and everything in it is trashed. I can’t/won’t reinvest in it, to not have any guarantees. If I stick a stock box in, then what? Detune the car? No thanks. That would be end of project for me I’m afraid.
My only hope for the car is that we find an issue that was caused either by assembly error, or extraordinarily unusual/rare circumstance that all parties agree is unlikely to happen again. If I can salvage some of my expensive parts, and source a donor casing (as I imagine the cost of replacing every single bearing/component will make a replacement make more sense) then maybe I can push forward and keep going.
I’m open to opinions on the nature of the failure, a few people have guessed at it but nobody is really sure - so it will be at least a little bit exciting to find out what went off.
Oh mate! I feel awful for you - I thought you’d built an indestructible C64! 
Oh thats a shitter and never heard of a failure like that.
You need to get the box out and stripped. With the amount of work (and £££) you have put in, that box should be more than capable.
Keep us all posted
Cheers Gents, yes it’s very annoying but I’ve been pushing things, and perhaps the sprint launches were a step too far.
Emotionally I’ve bounced from returning car to standard(ish) and selling, to fixing as-was and hoping it doesn’t happen again, to going totally mental and lobbing a K20 in… and various things in between.
I’ve spoken to a few specialists, some related to this box and the work it’s had and some not. The only theory that comes up is the broken input shaft one, which is the only thing I could come up with in the paddock during the immediate aftermath.
Ultimately I wasn’t going to be able to make any decisions until the box was out, one way or another this car needs fixing. Started slow with an oil drain and was surprised to not find much glitter. I ran the entire lot of oil through some coffee filters and all I came up with was half a dozen little glimmers.
The magnet inside the casing is probably covered, but still it made me a little positive that some of my expensive bits may have survived.
Getting a bit good at this now, but box was out probably over 2.5-3hours in a couple of stints.
Externally everything looks, feels and smells fine. I can select all gears (by feel) using the shift linkage and the diff seems to move in all gears when spinning the input shaft. This again would lend itself to the theory that the input shaft is sheared but the friction between the stubs is enough to apply ‘drive’ when there’s no drag on the output. As soon as the box is in the car with axles and wheels, the two stubs just grind away at each other.
I’m hoping to get the box to my rebuilder at the weekend and with any luck I’ll be taking with me a spare box. The spare box is a relative unknown, but the plan is to make a decision this weekend whether any of my good bits can be salvaged. If they can be, the donor box will be opened up, inspected and my bits will go in. If my bits are trash, the donor box will probably be left alone and thrown straight into my car with a plan to remove the ECU/power modifications and then see what I want to do next.
One way or the other my hope is to get the car rolling before Croft on 1st July. We’ll see if that turns out to be overly ambitious very soon…
Sorry to hear about your problem. Great write-ups as always prior to the disaster. Fingers crossed for a quick (and long-lasting) solution.
I feel your pain and disillusion in the words. To put so much time, effort and money into the project only for it to fail is devastating. My advice would be to not make any knee jerk decisions, ultimately if you can still get it working how you want this will just be another anecdote and when you enjoy driving the car in the future you’ll forget the pain it took to get there.
Or maybe this is the trigger to move onto the next thing? It sounds like you really enjoy the car though and from personal experience you’ll struggle to find an alternative that checks all the boxes that a properly sorted Exige does if you still want to spend your weekends at the track.
Gutted for you Kyle after all the effort on the 'box and car in general I’ve always been put off sprinting by how brutal it seems on mechanicals - maybe Blyton did push the limits from a cold/standing start that might otherwise have been fine on a normal track day? Hope it’s a straightforward fix for you anyway mate.
Thanks Gents, appreciate the sympathy but it is just a toy car after all. I’ve pushed it a little further than I should have done, and despite best efforts it just didn’t work for me.
I’ve had the box stripped today and there’s no real good news unfortunately. The failure was in the aftermarket output shaft, which came part of the Kaaz final drive kit.
As soon as we started stripping the box it became apparent that the shaft had broken. It just wobbled around like mad as soon as 5th and 6th were removed.
The carnage is minimal, but still enough to effectively write-off the gearbox. I went to visit the rebuilder with a donor gearbox in my boot, the hope was that if my 3rd, 4th and Final Drive (the expensive bits) had survived, then I could transplant them over and try again in a new box.
The 3rd and 4th survived, they look completely unscathed - but the FD is obviously written off, and we mutually decided that I could risk reusing the diff as we’d never really know how much crap it had ingested.
Considering the cost to strip the donor box, replace the single use items and rebuild with the 3/4 - it feels like throwing good money after bad. Although I’d like to sleep on it a few more times, I think the decision has been made to put a completely unmolested standard box back in the car instead.
I then have a choice to make… Do I:
a) Detune the car and run it happily within its comfort zone? This is likely to lead to the sale of the car, readers will probably appreciate that the project element of this car is most of the enjoyment.
b) Run it as is, with a standard box. I might get 2 laps out of it, I might get a decade - it’s anyone’s guess. In the name of science, it would be interesting to find out because if a standard box would last me a decent length of time, then it’s not totally out of the question to treat them as consumables.
The way I’m feeling, all signs are pointing towards detuning and selling on. I wouldn’t want to sell it running 300bhp without an uprated box, but if I knocked it all back a bit and got a comfortably 260-270 out of it, it’ll still be a belting car - but it just won’t have the project ceiling to keep me entertained for long.
In hindsight, running the standard box to destruction is absolutely the thing I should have done. I may have ended up with a failed gearbox sooner than I have but at least I wouldn’t have lost the better part of £3k (probably closer to £4k including rebuild labour and extras like the oil cooler) in the process.
I do think you did the right thing in trying to future proof and build a strong car, is there any history online of similar failures of that part? Seems like it is one of those really unfortunate unforeseen failures. I know you did a lot of research and careful decision making before you went down this path so you could drive the car how you wanted with peace of mind that it wouldn’t leave you at the side of the track. It seems so unlucky that this is what ended up happening anyway!
Option B is where I would be at right now. At least with the cooler gearbox oil temps due to the cooler it might last longer.
Or not.
You do love a gearbox hokey cokey dont you ?
Ultimately I would look to source an alternative to the Kaaz and get that fitted. This must have been a one off, surely?
I’m flipflapping like mad. One minute I’m all up for sending it at Croft on a standard box (with cooler) and seeing how much fun I have.
If I strip a gear, hey ho - £500 and another 5 hours of my time down the pisser… but I’ve just spent more than that on Nankang tyres, so it’s not bad in the grand scheme.
If it survives, and I have decent fun in a car without an LSD - then maybe I keep going for a bit.
Next minute I’m updating all my wiring documentation in preparation for pulling out the dash, ECU and returning it to the Lotus 260 map.
Waiting on a couple of gearbox sundries to arrive, so got a day or so to make my mind up before I start work.
just catching up on this… sorry to hear this Kyle - I too thought you had built the strongest car possible… I hope you decide to keep it - but I do understand your quandary…
Third option for me, rebuild the existing box with the good bits as you have intended it to run. I think you were just unfortunate.
Running a standard box would be niggling in my mind every gear change, incase it breaks.
Yeah I’d love to do that, but it’s going to be close to another £3k, bringing total gearbox spend to nearly 7. It’s too much, need to know when to stop throwing good money after bad, and admit the 2zz drivetrain isn’t going to keep me entertained.
To be honest, it really does sound like (without sinking more cash into it and then hoping for the best) you’re not going to find the thrill you’re looking for from the platform now…
I must admit I do keep looking at Caterhams - seems like a big thrill for not a huge amount of cash, and can be reasonably reliable from what I’ve seen? Is there anything on your ‘what next?’ list that would light your fire?
My “what’s next” list is quite varied, and keeps changing.
But, if you allow me to indulge…
Obvious answer seems to be the V6 Exige, the aftermarket/modification scene for them is really taking off now - and I could potentially still have some fun with some of the geeky stuff I’ve started on the Exige regarding canbus and gadgets. I’ll be honest though, I see one next to an S2 - and the S2 tweaks my trousers the most. Personal preference, but I find myself getting drawn in to the expensive/exotic end of the V6 range to allow me to overcome my S2 fetish.
Caterham is a very real consideration, I’ve wanted to build a kit for as long as I can remember. It’s not without its downsides though, it’s a proper fairweather car - wet/cold trackdays really would be miserable even if I am now an established tower! This sounds petty, but I also feel like they arrive “too built” for me, seen photos of delivery day and it’s pretty much a whole car being dropped off with a dozen boxes! Bolting on some wishbones and seats isn’t my idea of building a car, but I’d like to think I’ll find ways to make it more involving/difficult for myself. Buying a prebuilt Caterham has zero interest to me.
Had a half hearted look at Ariel Atoms, serious bit of kit - and fantastically put together. I feel like they’re a bit beyond my driving ability though, the Exige is pretty knife-edge as it is, and the Atom is just all of that on steriods. The Caterham appeals because I think I could achieve comparable laptimes whilst advancing my driving at the same time.
Another contender was the Lotus 211 that’s currently on the market. Not sure I could get my car fixed and moved on quick enough to move on that specific model but the idea of transplanting all of my “bits” onto a platform that’s almost identical did sound attractive. “But it still has a 2zz/c64” I hear you cry, yes it does - but a 211 running a comfortably 260bhp would be more performance than I have today. Maybe I could keep it relaxed, and still get what I want from it. I then get to thinking that a 211 is all the bad bits of an Exige plus all the bad bits of a Caterham…
It’s a massive stretch, but if I could run an Elige and a Caterham concurrently, I think that would tick all of my boxes. Treat the Caterham as the ‘extreme’ car, push performance on that and make it my perpetual tinkering project. Run the Elige at a comfortable level of tune, and just run it whenever it’s cloudy. (or whenever the Caterham is broken)