I managed to put a stop to all other squeeks but theres just this one squeek that I cannot get rid of. This squeek comes basically when you pulling away or jerk the car (i.e release clutch quickly, pull aways). I have changed a broken mounting, i had other things tightend up, i had the exhaust/header checked out an tightend and tried things, but no luck. This squeek comes from the outside of the car, more towards the front end.

Can anyone help me out?

 

Good job making your MINI more stealthy....Sounds like what ever it is, only happens when a load is placed upon some rubber/wearable part. Could be a worn out sway bar bushing. They are a bear to replace, subframe up front has to be dropped. If you do, I would suggest replacing them with Powerflex brand eurathane bushings. They will last much longer than stock.

Could also be just a worn strut - How many miles on your R53?