If you're heading to Spa today or tomorrow, keep in mind that there are major roadworks on allmost all the roads to the track. E40 in Barchon is on smaller lanes, max speed 90 km/h (watch out for radar) and at the final part of the E42 before the exit Francorchamps there's only one lane open. You could take the exit Spa and then head to Francorchamps over the B-roads.
Leave early, 'cause it could be a real pain to get to the track tomorrow.