Honda have spent seven of their remaining tokens on upgrading their engine ahead of this weekend’s Belgian Grand Prix.
Honda have updated their combustion chamber, turbocharger and compressor.
Fernando Alonso and Jenson Button will run the upgrade in Friday’s practices after which a decision will be made as to whether McLaren will race it for the remainder of the weekend.
The upgrade means the McLaren drivers are closing in on grid penalties as using a sixth power unit component carries a 10-place grid penalty.
Alonso will move onto his fifth of all six components whereas Button is on the limit of the allotted number for all excluding the Energy Store and Control Electronics.