The wheelbase mod I developed a few months back and told Ari and Jake who both tried it and liked it (I think!)
The idea was not solely to simply shorten the wheelbase. The C4.1 is an improvement on the C4 euro so it would be rediculous to use an old car for this reason!!
The real reason for changing the wheelbase is in the static weight distribution. Most people who have shortened the C4.1 wheelbase have moved the rear arms forward but what this also does is move the weight distribution more over the rear wheels and away from the front, which is a bad idea I reckon when more on power and high speed steering is desired!
What I did was move the front arms backwards so that the weight distribution is moved more over the front wheels.
By moving the arms back ~6mm the weight dist. becomes about 50% front/rear which I found was way better on the track. The kit layout/wheelbase before this mod leaves about 30 grams more on the rear end than the front, this is about a 2% change but seemed to make a big difference to the steering ability of this car.
BTW I have taken some pics of my car including this mod so hopefully will get them sorted and formatted and on my site soon.