My Mk1 Octavia VRS is fitted with Falken 225/40 R18 tyres, LCR topmounts and APEX coilovers. On the highway there is a lot of noise over 80 mph, I guess tyres are due to this. Would Michelins or such help? Or should I go to 225/45 R18 (yes it's big) tyres? Due to the LCR topmounts the car is noisy and feel uncomfortable over potholes and such. I guess normal VRS topmounts would help? Has anyone tried bitumen and does this help getting a more solid and comfort feel?

I switched to Vector 4season G2's - Road noise drastically reduced and felt pretty nice drive wise until I hit twisty roads. The handling is a bit vague. Check the thread in the tyre zone about Michellein cross climates.

Have you looked at something more than 40 and also a tyre with a better dB rating (if it exists) ?

pilot sport 4's are pretty decent for road noise

Hello, sorry for the delay in my answer. I just noticed I had mail from Briskoda... I could experiment with different tyres. I do believe the Continental ContactSport 3 where better in, but these were 205/50 17 (about the same as a 225/45 17 tyre). I cannot go back to 17” as the 370 mm brakes prevent otherwise. Only option would be a 215/45 or 225/45 18” tyre.

My old Scout had Falkens (unsure which) on it and it was horrifically noisy.  I swapped them to Continental Winter Contacts all round and instantly the road noise was reduced.  Also the Falkens (which still had half the amount of tread on them when changed) had worn unevenly, yet the Continentals that needed changing a year later had worn evenly.