How robust are cooper S engines/superchargers

[E-bmw]

I have asked this in a roundabout way in the track day forum with no specific answers.

As above, are they robust enough to take a bit of abuse on track/mileage beforehand?

I am considering one as a new track day project & am curious.

I know with reduction belts & pulleys, upgraded intercoolers, decent exhaust, proper inlet kit they are good for 240+, but do they last?

Even with part of the above does anyone have any direct experience of these?

[mon the fish]

The engines are very tough - the internals themselves can take nearly 400bhp AFAIK. There's been some mega-power builds on MiniTorque.

The superchargers themselves do eventually go. The most power you can make with the standard blower is about 280bhp, that's with a 17% pulley or smaller and other mods - but that's as much as the charger will pump, as the heat it generates as it spins faster kills the power.

What goes on the supercharger is the gears - the oil is generally never changed, and the gears and oil turn to mush. The oil can be changed, but isn't normally. Normal lifespan (without oil changes on the charger itself - there are kits on ebay for this) seems to be anything between 100k to 140k miles. I've put 80k miles on mine, all with an 11% pulley, and it still makes good boost. I'm planning on changing the charger oil sometime soon, just not got round to it.

I'm running 230bhp with zero issues, and happy with that level of power

[CarsOrBikes]

If it's on track with a pulley change I would get it mapped (tailored map) personally, many say you don't need to but it will be better for it. On reflection I would consider fitting a 15% pulley over a 17% that I have now, due to the intake heat at sustained high rpm. I plan to alter it some more which just adds to the problem, although a water/meth kit will address this as others may tell you. Mine is currently at around 255 but has the standard head still, not for long. Intercooler is from a GP and essential in my opinion. Also I used an interference fit pulley rather than the usual bolt on style which most don't have issues with, but if they slip or come loose it would be a mess somewhere. The engines can take up to 650bhp I'm told, and increasingly they're turbo'd to get to easy 400's. This is not a cheap conversion, but novel.

If I was buying a cheaper car and doing it again, I'd go with the same mods but with different rods and pistons, high rpm valve train, arp bolts top and bottom, from the off, but also lower final drive, and alternative gear set, which i'll do to this one soon, but as it's a standard looking nice road car, it is getting expensive already.

1320 will give you advice

I took this on track in Dec at Anglesey, and Feb at Oulton for longer after some other changes, and it was ok, waiting to try out some other alterations soon.

Brilliant things in my opinion, best version.