I recently bought a 2023 F54 JCW. The top speed is limited to 155. I have had the car for about 2 months now and hit a top speed of 143mph(could have gone more but had a turn coming) that was a month ago. As of last week the fastest it will go is 131. Peddle to the floor (3500rpm in 8th). Dropped it to 7th and still at 131. Up to this point there have been no modifications. Since then I added a JB4, Eventuri intake and Airtec intercooler. Now it is much quicker but still limited at 131mph. Anyone have this issue with top end changing or know how to get rid of the limit altogether? Thanks.

 

This part of the forum is for Gen 2 JCWs.You need to be in the Gen 3 section.