I have a big head, got to fill it with something.
150Nm- yeah that's probably right for a design case, FOS (facor of safety) I'd guess at 1.5 times declared (225Nm with ATV) which is probably about right. Fudge factor comes in when the 084 box is so similar to 085 and that was designed with 45bhp in mind!! D'oh.
Driving style, available traction, and torque delivery do have a massive impact upon life. I've found since being able to get full traction in second (requires a meaty passenger, slicks, subframe etc etc) that second gear goes! Before the wheels just span!
Driveshafts aren't too bad, there's various companies which will make them (custom) for £160/side so you could use a Golf inner joint, and Polo outer joint if you wanted to retain the Polo hubs.
However, in the spirity of upgrading things, if would be a shame not to switch to a Golf hub & use a larger CV- I don't think the Golf hub fits in a polo upright, so que changing the uprights/steering arms/top mounts.
Wonder if the spline on the gearbox can be changed easily.
The 02* series of boxes are very readily available, I've got a huge spreadsheet of them at home, all with various ratios if it's of use.
Sequential is awesome, but also requires a form of torque reduction during shifts, be it through ingition retard, or fuel cut- either way it's not happeneing on Digifant, so more expense on either a gearbox control unit (GCU) or a decent ECU which can handle shift inputs/control loop too. I've never used a sequential or set on up, but I think you'd also need a strategy for failed shifts etc too, not that simple.
Clio 172 Cup Cars used Sadev boxes, when I used to read the Cliosport.net forum a few people had them on road cars, required oil changes frequently (1k miles) and a fair amount of upkeep- which a motorsport box is designed as such gearsets are eas to change/inspect. I get the impression they're crap at low speeds and tip in/tip out throttle conditions, and generaly very clunky, being ither semi-helical or straight cut teeth.
