what tires should i use in FBM? I use default set(R2). My tires go so bad in 4 laps, that i cant use gas in corner or i start spinning instantly. and no, I dont burn tires

R1 tyres are fine for me in 5 lap races so it's probably your driving style.

I find the default set to be really bad, though. You should go here and use one of these.

or you could try R3 tires

R1s are now more like qualifying tyres, so wearing them out after a few laps is to be expected. They can still last full races of course, but it depends on the race length. Try using a tyre compound with lower wear, such as a the R2s. It could also be your setup at fault, so maybe ask on a server for a new one and see if that improves things. If not then you need to change the way you drive.

The default setup seems to use too much camber and too high pressures, so the inside edges get red while the outside edges are still cool. Grip is very low in these circumstances. Adjust your setups to load the tires more evenly. You'll have more overall grip and R1s will last longer. On short races such as those on CTRA, R1s should always be able to last the distance.

If you find that your fronts are still wearing too quickly, adjust your driving style. Use a gentler, earlier turn-in in order to maximize the moment of best rotation. Try to use as little lock as possible. Your outside tires should be right on the edge of the track at the moment of turn-in. If they aren't, you're using less of the track than is available to you. Good drivers will punish you for that.

If your rears are wearing too quickly, adjust your diff to help you on corner exit and try to be as smooth as possible when putting the power down. You should not have to countersteer to keep from spinning on the exits of slow corners.