Help with tire sizes

[BoostedAvus]

Ok so there is a lot of thread for stock M5 comp wheels 343m with 305/30/20 on the rear but not really much on what people do front tire wise.

Is stock tire size ok? Or do I need to be 275 or 285? It’s hard to find a general consensus.

Thanks for the help!

[Blaxwil]

275’s in the front will work on the stock set up but you may get some rubbing during turns. 285’s would stretch way too much and be unsafe in my opinion. Remember, the stock wheel is designed to run 265’s.

305 in the rear and 275 in the front is about as aggressive you can be with the stock setup sitting on regular tires such as Pirelli or Michelin.

I’m currently running 305/25/21 in the back with 275/30/21 fronts. Lowered with KWHas V4 coil overs. No rubbing even with 3 passengers. I had a previous set up with 325/25/21 rears and 285/30/21 front. Again, depends on your application. If I were you, I’d stick with the very proven 265/305 and call it a day.

[BoostedAvus]

Thanks. Yeah I’ll probably for now stick with the 265 / 305 see how it goes. I have been eying the apex vs5rs. Haven’t really looked at any 21s.

Really looking for any added grip over my pss currently. Hoping the 305 ps4s gets me no spin at 60

[m5rosco]

Originally Posted by BoostedAvus

Thanks. Yeah I’ll probably for now stick with the 265 / 305 see how it goes. I have been eying the apex vs5rs. Haven’t really looked at any 21s.

Really looking for any added grip over my pss currently. Hoping the 305 ps4s gets me no spin at 60

What pressures do you run?

You could go 275 up front if you really wanted to, but the tyres look a bit too wide for the rims, and you'll find the car tramlines noticeably more. Personally I even think 305's look too big for the stock 10" rims, and will you really notice a difference having 3% wider rubber? I think most people that report an "improvement" are comparing fresh, new, supple tyres with old worn out ones, but that's another topic/argument!!!!

[BoostedAvus]

Originally Posted by m5rosco

What pressures do you run?

You could go 275 up front if you really wanted to, but the tyres look a bit too wide for the rims, and you'll find the car tramlines noticeably more. Personally I even think 305's look too big for the stock 10" rims, and will you really notice a difference having 3% wider rubber? I think most people that report an "improvement" are comparing fresh, new, supple tyres with old worn out ones, but that's another topic/argument!!!!

Right now i dont have 305s i have 295 PSS. Running pretty much whatever is on the door jam, would have to go out the the car the check. The PSS have decent tread but are a few years old so was looking at PS4S 305 to replace.

[m5rosco]

Originally Posted by BoostedAvus

Right now i dont have 305s i have 295 PSS. Running pretty much whatever is on the door jam, would have to go out the the car the check. The PSS have decent tread but are a few years old so was looking at PS4S 305 to replace.

Makes total sense. Fresh rubber will definitely help if they are a few years old as they will definitely past their best, no matter how little wear.

On the topic of pressure we generally find running about 34psi front and 30psi is a decent balance between comfort, handling, and straight line grip.

Hope that helps.

[M5Rick]

Originally Posted by BoostedAvus

Thanks. Yeah I’ll probably for now stick with the 265 / 305 see how it goes. I have been eying the apex vs5rs. Haven’t really looked at any 21s.

Really looking for any added grip over my pss currently. Hoping the 305 ps4s gets me no spin at 60

I have 305's ps4s on the rear and definitely less chirping than when I had the 295's, that extra cm helps a lot with grip and as mentioned by M5rosco it's best to keep to the 265's for the front to avoid the unwanted tram lining.