IIRC I've heard they rub the arch liners, but not the suspension. But only if memory serves me right, I've never run more than 35 profile 18's on track. And the 35 profile don't rub the arch liners.
I think the 40 profile will be too much as a track tyre and you'll have hardly any turning circle, they will miss the suspension turret but it'll be close.
Just run a set of 16's as we know they work well even if the tyres are a good price.
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