Kumho Ecsta KU39 vs Kumho Ecsta PS91 — Compared

“Pretty terrible idea, the PS91 will not have the same heat capacity as the V730, so your front/rear grip balance will change wildly during a session. With the non-200s on the front, at least you’ll understeer instead of oversteer/spin, but not ideal. An experienced driver might be able to work around this, if you’re new, this would be a dangerous situation. Similarly, I wouldn’t mix something like a yokohama AO52, which delivers all of its grip from cold and tends to overheat within a couple laps, with something like a hankook RS4, which famously takes some time to warm up and then delivers consistent grip for a long time”

“I've only got a couple thousand on them and just spirited driving in the mountains. I think they will easily go over 10k even with a few track events. I am thinking about getting a set for my SVT focus as I autoX with that car, much easier to drive at the limit than a turbocharged S197.”

“my turbo came with a set of Kumho Ecsta PS91 in the OEM widebody sizes that were around a year old and had maybe lost 15% wear. coming from someone who loves PS4S, i hated them. grip was subpar. it felt wasteful to toss them though since they were relatively new and had decent tread left so i toughed them out. i got maybe 2k miles out of the rears before they needed replacement just from normal street / occasional spirited driving. they are not a great handling tire and they are quite bad from a wear perspective as well. just buy michelin or even continental and don't look back.”