McLaren have arrived in Spa with several updates, looking to increase the performance of the MP4-29, mainly centred around improving the airflow structures at the rear of the car. As we have seen over the last few races the team have started to move away from the use of their 'wishbone wings' as the concept although sound hasn't produced the type of performance they require. Furthermore as the design of many components was made to cater for them making widesweeping changes has taken time.
With changes to the 'wishbone wings' and diffuser already mentioned: McLaren MP4-29 - Diffuser - Spa we must now turn our attention to their new rear wing. Having implemented several design changes to their rear wing in Hockenheim which was used again in Hungary and with a switch from high to medium downforce (with a large emphasis on drag reduction for the long straights) the team introduced another new design.
Also worth noting is that the team are not running their Y100 Winglet / Monkey Seat this weekend (usually attached to the Y-Lon)