Unfortunately, McLaren does not sell the 540C in the US market (despite saying they would) which is a shame as it provides the best tuning value in the McLaren lineup. The M838T under the hood is the same basic 3.8 liter as its big brother 570S as well as the other M838T powered McLaren models like the 650S.

Click here to enlarge

McLaren reduces the redline for the 570S/540C and with software reduces output on the 540C by 30 horses compared to the 570S.

Tuning gets that lost power back and then some. Just look at what it does to this stock 650S:

We wish we had a dyno overlay to show you but we do have stock overlays for the 570S, MP4-12C, and 650S if you want to take a look.