Max950 I don't know if I'm honest mate it was mapped by td years ago when I first set the car up and at that time there wasn't a rolling road , so I never put it on one And I dunno why it never shit itself as I've always wondered that but I just looked after the engine Services it every 8-10 weeks when I was using it daily and just generally maintained it like I say just fitted tdo4 2weeks ago n my mate that works at vauxhall did me a compression test before fitting said my reading where still very good