07/12/2026
Post 2 of 5 in our TWS Tech Series.
Q: What are top hat liners and how do they help? Do you install them on every motor?
A: A major fault of the Rover V8 is liners slipping and causing coolant consumption, overheating, and/or knocking. Since the stock liners have nothing stopping them from moving down, and the thermal expansion differences between aluminum (the block) and cast iron (the sleeve), it is almost inevitable. We top hat all of our motors, except the 3.5 as we do not see this issue due to the small overall bore size,, resulting in a thicker liner.
