I'm not sure if this belongs here or in the mods section, so please move if necessary.
I recently picked up a 2004 Cooper S with 111k miles. The alternator went out on me the other week, and it had a top end oil leak, so I decided I'd replace a ton of stuff while I've got the intake side taken apart. Here's the list off the top of my head. My question is, what else should I do at the same time? Here goes:

intake manifold gasket
s/c green gasket
throttle body gasket
s/c to horn gasket
crank angle sensor gasket
exhaust manifold gasket
valve cover gasket
PCV valve
thermostat w/ gasket
waterpump w/ gasket
BMW rebuilt supercharger (new black impellar style)
Alta 15% pulley
serpentine belt (for 15% pulley)
idler pulley
DT tensioner stop (shock and pulley look fine)
JCW 380cc injectors
Power steering fan w/ aluminum cover
powerslot front rotors
ate slotted rear rotors
hawk perf ceramic pads
caliper bushings
front/rear brake hardware
braided lines
ate brake fluid
fuel filter kit
reverse light switch
powerflex control arm bushings
powerflex big/little lower motor mount inserts
powerflex rear trail arm bush
powerflex steering rack mount
powerflex gearbox mount
UUC 19mm rear sway with hotchkis bushings
TSW springs


Already installed:
BMP intake
Detroit Tuned BPV
Milltek header/cat
Milltek exhaust


Whew.... I think that's everything. What else should I replace while I'm at it?

 

I had to replace my radiator a year ago due to a leak. Last week, the cooling fan crapped out so again a tear down. Might as well replace all of the hoses while apart. Have fun---

 

Any reason for wanting to the new SC other than the coating. If you replace the fluid in thing it's not it will really wear out.

 

I think you hit just about everything. If you are rebuilding/replacing the SC, you can opt to go to http://www.stiegemeier.com/home.html. Their prices are very reasonable. I think the brass caliper bushings are a great low-cost upgrade.

The JCW injectors are optional. Only tuning will tell you if you will need them. I'm still tuning mine with Jan at RMW, and I have not bought them yet. And definitely get a tune when you're done.

 

I just bought an 04 MCS with 116k miles on it. I did not do nearly this much to it. I did a PS Pump & Fan replace, O2 sensors, spark plugs, coolant flush, brakes (pads, rotors, fluid), Trans oil change, air filters. Had to wait for the fuel filters to get here, but doing that tonight along with the Belt.

Good luck with everything else you have listed.

 

I'm well aware that 90% of what I'm doing is currently unnecessary. But, this is a second vehicle for me, and I won't need it until November. So I figure while I'm at it, I'll replace pretty much everything that can wear. I got a great deal on a BMW factory rebuilt S/C with the black coating, so I bough it and will resell mine. Everything else I bought off the marketplace, rock auto, and ebay for good deals. My best deal was the alternator with <40k miles for $55 shipped! I forgot to mention I replaced the coil, plugs, and wires as well. I autocross regularly and I'm looking forward to taking this car to the auto-x course and perhaps BIR or Road America. But it will truly serve as a winter vehicle, and now that I found out my wife is pregnant last week, a daily driver during the summer when I need to tote around junior.

I plan on getting a remote tune from RMW after all is said and done. I went to BMW to get 4 things today: green s/c gasket, S/C-horn gasket, CPS o-ring, and a small bolt for the intercooler, and it cost over $50. I hate dealer prices, but there's a few things I can't source online. I've been contemplating p&p the horns, IM, and perhaps even headwork, but I just can't justify it as this isn't even my "sporty" car . Anyways, I'm open to any ideas or criticizm. Tell me what I'm doing wrong or what else I should do. If you can't tell, I'm thorough with my cars.

 

Ok, I'll bite.... What is your sporty car???

 

Nothing amazing. I've got an 04.5 350z and a 95 Miata. The mini is like a perfect combination of those two cars.