I agree. Just did the one-ball mod on my MC40 and it turned out great -- a bit more sound (especially on the top-end), but not obnoxious. Can't imagine why BMW ever thought two restrictive resonators/mufflers in sequence was a good idea. I originally thought about a cat-back system but couldn't mentally justify the cost -- $100+ per hp seems WAY excessive to me. Along with the 15% SC pulley I installed, it's really woken up the little beast - having a blast driving it. I'm now thinking about a JCW head (or similar) and would like to know if anyone else has made this mod, thinks it's worth the cost, and has measured the HP increase?

 

 

GreenBean, the 15% pulley is extremely noticeable. I've read that the 17% increases heat levels and unless you have an improved intercooler and are tracking your MINI, it probably doesn't make sense for a DD. I have the 15% pulley, a mild exhaust mod and a Dinan Stage 1 tune. I estimate that it's making around 192hp which makes it a low-cost, fun, driveable and very streetable MINI, and with it's light weight, can more than surprise a few 3-series Beemers.

 

 

Tune was on the car when I bought it and I came across the paperwork post-buy (looked for it today but can't find it at the moment). Check this Forum for tune providers that can remap the ECU remotely if you send it to them. The Dinan Stage 1 tune bumps the stock MCS from 163 hp to 175 hp (12 hp increase). Conservative estimate on the 15% pulley is a 15 hp increase. The "one-ball" exhaust mod is worth maybe 2 hp and cost me $100 [done primarily for the weight loss (30lbs.) and better sound]. Bottom line: I got a 17 hp increase (pulley/exhaust mod) for around $200. Added to the tune you're talking 29 hp which has made a huge difference, but the pulley alone produced the most smiles -- well worth the expense. I've also swapped out a number of seals/o-rings/gaskets plus fuel filter, coil, plugs, valve cover, rear shocks, tires, added an auto-window switch, oil change/filter, replenished SC oil, changed thermostat & housing, new timing chain tensioner and a few other odds/ends and I'm still only into the car for around $6k (including purchase) which is a real bargain considering all the fun I'm having with it. I do all my own work (except the exhaust mod) so I haven't added labor costs. My 70th birthday rolled around recently so I sold my motorcycles and the MINI is a somewhat safer substitute. My son just gave me drilled/slotted rotors & ceramic discs (all four corners) for Christmas so that's the next cool project (waiting on new rotor screws to arrive). I think you'll find that the MINI is going to provide you with many hours of enjoyment and that this Forum can be an invaluable resource. Also be sure and check out ModMini on YouTube. He has some amazingly helpful repair videos posted.