A focus has the best weight distribution he's ever seen?I have a friend that is prepping his car for the track right now.. my car does not land for another two weeks but the weight issue is one I have considered due to my dedicated racing purpose..
For street cars reducing large amounts of weight can be an issue without height adjustable coilovers.. once that weight most of which will come from the rear comes out you will unsettle the rear causing some oversteer not to mention you wont like the look of it's bum sitting up high.
He has done corner weights on the car and I have been told that the balance is the best on the corner scales he has ever seen on a production car.. so think carefully about removing weight ..
A good start is a quality lithium battery.. which are 1.7kg or just under 4lb and have 700 crank amps.. In my other cars I have placed a breather tank in the empty portion of the battery tray.
In short you can reduce some but until height adjustable coil overs are installed you will find things a bit awkward