I have a diff, Kaaz close ratio gear set and a 4.3 final drive.
Very kind cheers Andy, I’m notoriously nervous about driving others’ cars and to exploit the chassis enough to the point a diff will make a noticeable difference is unlikely to happen 
Perhaps if we end up at together in the near future we can do a switcharoo… only if you dettol your steering wheel first.
Interesting, the Kaaz gearset is something that does look attractive - it’s not just toughening up the system but it’s optimising it for performance too… that makes it an easier cost to stomach… but it’s still a crap load of money 
I’ve seen the ‘gearset’ advertised on a few different websites, does it typically include the FD or is that extra on top?
[mention]seriouslylotus[/mention] what are your thoughts on gearbox cooling? I know you used to sell a kit but I don’t see it on the website anymore, I read such conflicting information about whether it adds anything at all. Obviously people who have invested in it are going to say it’s critical, people who won’t/can’t invest in one will diminish its value - that’s just how car modification opinions work unfortunately!
Good question and one i intend to find the answer too
I have just installed an AIM dash in the yellow project car along with oil pressure, oil temp and gear box temp sensors.
As a road car i doubt any cooling is really needed but on track i suspect that the gear oil will get very very HOT.
I still have a gearbox cooler kit put to one side, decided i would test the temps before adding unnecessary weight and additional heat exchanges etc etc. Keep it simple is what i am saying, only add shite if its needed
Cheers Dave, that’s good info and good to know you’re going to science it out first!
As C64 gearboxes are fairly easy to get hold of and fairly inexpensive, is there an argument to just “see what happens” when the torque starts creeping up to 190ft/lbs (or whatever the considered ceiling is)? I know people who are tracking/sprinting stock C64’s with over 300bhp and so far nothing has gone bang, but I know of others that have failed at under 260, seems to be a bit of a lottery in that regard. What’s the worst that can happen in terms of collateral damage if a gearbox goes bang? Any danger to the engine or would the disaster be self contained in the box?
All would fail in the box. The highest rated exige engine was 176ibft from what I can tell.
I don’t know if the ones that went bang were maintained well, or shocked into failure by wacking kerbs.
Don’t believe all you read about 300hp S2 exiges!!!
Yep indeed, hard to know what to think. Failure does seem inevitable but if that inevitability could be 20,000 miles away… deferring the spend on preventative upgrades seems like a half sensible idea. I like to think I’m mechanically sympathetic but who knows how much time that’s buying me, if any.
If the box is coming out for diff/clutch/flywheel etc, I’d probably want to do SOMETHING so maybe an interim solution could be the 3rd/4th gears (seem to be the most delicate part?) and then suck it and see. You can just spend silly money by replacing everything that might one day break.
Yes fair comment, I do know somebody with a REV400 kitted 111R though who tracks/sprints the car and so far the gearbox has held up… not sure if the car does any road mileage though so keeping miles down on it might be a mitigating factor! Hopefully I’ve not just jinxed him 
Exactly what I am planning.
I am prepared for failure but not planning on it!
Yep seems like a pragmatic approach, though the Kaaz set does look very entertaining for blasting through the gears on track. 
Got my USB endoscope out last night and had a peek up at the crank pulley/sump area - after 300ish miles it’s still bone dry so I’m getting nervously confident that I did indeed solve that leak with the crank seal which is a relief after the cost of changing the pulley etc.
Still I won’t believe it’s fixed completely until later in the year when I get some real mileage on the car (hopefully!)
eta:
With our lock down announcement I’m going to draw up a small list for a bit more tinkering, there’s a temptation to bring forward next winters’ plans but that might require 3rd party involvement which I just can’t be sure of at the moment, plus we’ve got no idea when the lock down will be lifted so I don’t want to have my car in a thousand pieces again, needs to be ready for action at a moments notice!
My tinkering is on a more modest scale . I managed to repair my driver’s side window winder for the umpteenth time after our Sunday run out using the tried and tested method: a hammer.
The problem is that the serrated ring which grips the shaft of the window “turner” slips off periodically. But there will come a time when brute force and ignorance will no longer work. I think a few pics might have helped make my explanation more clear 
Regarding the gearbox, if you are going internal then would recommend the uprated final drive. I pulled 5 teeth out of the std one at Anglesey. Other options it to treat it as sacrificial and just have a spare celica box to throw in if you do have problems.
Cheers Evo, silly question I’m sure but can you mix and match final drives/gear sets? For example the SCC gears would probably be my favourite based on availability and the fact they’re not straight cut but I can’t find that they do their own FD. Can I mix their gears with the Kaaz/Jubu FD for instance?
Yes I believe you could mix them although I went with full Jubu set.
Cheers for that, I feel I need to experience the full jubu set before making a judgement on how it sounds. Some gearbox noises are cool, others I struggle to live with!
I originally had their straight cut final drive, that definitely wasn’t cool, hence going back to std. Unfortunately then immediately regretted it when it broke, hence doing it again with their semi helical final drive. Noise from that hasn’t been an issue. Only reason I had straight cut initially as at that point they hadn’t brought out the semi helical.
The semi helical setup sounds kind of cool, give you a bit of the noise like an old mini gearbox.
If Jubu (still) do a semi helical kit then that’s probably where I’d end up if needing to refurb the gearbox. I can’t find them list anywhere which makes me think they may no longer be available, but obviously if/when I’m in a position to require them then I can step up my enquiries a bit. Doing so now with vendors would be wasting their time!
Excellent, so they do still exist 
Thanks for that link ade.