Not sure rake will alter the F/R weight distribution much and yes, getting diagonals roughly equal seems to be how most set up a 7. I thought rake was more to do with how the car handled and presumably being able to put the power down quicker (but hey am no engineer!)? In terms of what weight distribution is best, my 1988 7 started with about 50/50 and BMW ads for years have said that was the perfect result. For a low powered LR Defender offroad in a field that makes sense too. However, in competition circles my understanding is engineers are usually looking for more weight on the back. Writing in a classic car mag a while back, Tiff Needell reckoned 40/60 was perfect. I've tried very hard over the years to get away from 50/50 and am up to around 47/53 (all figures with just me on board) and am fairly happy with that. That has included a CF nosecone, ali rad, ali XFlow head, no heater, battery and washer bottle in boot, only one horn and so on. One of the reason the 911 has been so succesfull in motorsport has been its rearward weight bias, despite the engine being in the wrong place and it acting like a pendulum (what engineers call having a high polar moment of inertia - the opposite of what we enjoy in our 7s). Having less weight at the front means better traction on starts but also better braking (braking transfers weight to the front so you still have some rear weight so the back brakes can do more), you can trail brake or be off the throttle in corner entry (a bit of deceleration will give you 50/50 balanced cornering) and the the car can get maximum traction by having max weight on the back under acceleration so you can accelerate earlier. All this is only possible due to modern tyre grip (hence 50/50 was fine back in say the 1950s). At least that's my understanding (stands back while everyone who understands these things proves me wrong... :-)).