The only way you could make an SLR better would be to reduce its weight like the McLaren engineers have admited. To do that you would have to get reduced of all the MB options. A/C, radio, Airbags and so on.
Around the 'Ring the SLR is already the fastest road car. It can do a lap below 6min 30s no problem. Only the Enzo and Carrera GT can be a lttle faster when driven by pors.
However, on the rain, the SLR owns both of them [:0]
The SLR has 626BHP DIN, 780 nm torque, 3.8sec 0-100km/h, tops 330 km/h. The Carrera GT got 7:37 around the ring, I believe. Driven by Walter Roerhl, Porsche test driver. Have they run the Pagani around it yet?