Tyre Profile: 235/35/R19 + 265/30/R19 or 235/40/R19 + 265/35/R19

[pwnber]

Running 19" staggered, 8.5" width front and 9.5" rear.
Prefer 235+265 over stock 225+255.

35+30 runs 1-2cm smaller diameter than stock. wheel gap looks bigger!
40+35 runs 1-2cm bigger diameter. but not many seem to stock this size - PSS/GY Asy2.

Which tyre size would you use of the 2?

 

[totoseow]

Re: Tyre Profile: 235/35/R19 + 265/30/R19 or 235/40/R19 + 265/35/R19

I will use the smaller. lighter is better.....

 

[Baby1M]

Re: Tyre Profile: 235/35/R19 + 265/30/R19 or 235/40/R19 + 265/35/R19

Running 19" staggered, 8.5" width front and 9.5" rear.
Prefer 235+265 over stock 225+255.

35+30 runs 1-2cm smaller diameter than stock. wheel gap looks bigger!
40+35 runs 1-2cm bigger diameter. but not many seem to stock this size - PSS/GY Asy2.

Which tyre size would you use of the 2?

Is your stock 225/40/R19 + 255/35/R19?

If yes, 235/35/R19 + 265/30/R19 should be the correct upsize (not 35/40/R19 + 265/35/R19) because the 35-30 is a percentage of your tyre's width i.e. 35% of 235 and 30% of 255, also there overall circumference difference from original is less thus speedo reading 'errors' from original is minimal.

 

[Baby1M]

Re: Tyre Profile: 235/35/R19 + 265/30/R19 or 235/40/R19 + 265/35/R19

Running 19" staggered, 8.5" width front and 9.5" rear.
Prefer 235+265 over stock 225+255.

35+30 runs 1-2cm smaller diameter than stock. wheel gap looks bigger!
40+35 runs 1-2cm bigger diameter. but not many seem to stock this size - PSS/GY Asy2.

Which tyre size would you use of the 2?

Is your stock 225/40/R19 + 255/35/R19?

If yes, 235/35/R19 + 265/30/R19 should be the correct upsize (not 35/40/R19 + 265/35/R19) because the 35-30 is a percentage of your tyre's width i.e. 35% of 235 and 30% of 255, also the overall circumference difference from original is less thus speedo reading 'errors' from original is minimal.

 

[pwnber]

Re: Tyre Profile: 235/35/R19 + 265/30/R19 or 235/40/R19 + 265/35/R19

Both sizes seem ok after calculations.
235/35/R19 + 265/30/R19 runs closer to 17" stock size. 235/40/R19 + 265/35/R19 closer to 18" stock.


For the F30 stock rims:
1. 17" (F/R): 225/50/R17. Tyre height (22.5*50%*2+17*2.54) = 65.7cm
2. 18" (F): 225/45/R18. Tyre height 66.0
3. 18" (R): 255/40/R18. Tyre height 66.1

R19:
1. 235/40/R19: 67.1cm
2. 265/35/R19: 66.8

3. 235/35/R19: 64.7
4. 265/30/R19: 64.2

If you consider M sports stock tyres the ideal size, you should run 235/40/R19 + 265/35/R19. Most cars (including myself) run 35 and 30.

I will go for the bigger size the next time for aesthetics and comfort reasons. Reduced wheel gap by 12mm, slightly higher comfort with more side wall.

 

[Baby1M]

Re: Tyre Profile: 235/35/R19 + 265/30/R19 or 235/40/R19 + 265/35/R19

Hmmmm, if stock is 225/50/R17 (F/R) then for 19", all the more reason to use stagger at 235/35/R19 + 265/30/R19.

Sorry that i misrepresent the wheel circumference thingy, i was refering to the overall wheel's rotation which ultimately affect the speed reading from stock i.e. less error.

- accuracy of the speedometer, stock size at 100km/h, u get 101-102km/h compared to 105-106km/h (235/35+265/30 and 235/40+265/35 respectively)
- aesthetically nicer while the tyre-to-chassis gap can be adjusted. Big/high/fat tyre height/wall is not aesthetically nicer while comfort level difference is minimal.

U may wish to use the below link for speedometer calibration check as not to mess up your speed reading too much.
Speedometer Calibration / Tire Size Change Calculator

Anyway it is IMHO. Overall owner happy can liao.

 

[primus2211]

Re: Tyre Profile: 235/35/R19 + 265/30/R19 or 235/40/R19 + 265/35/R19

Throwing all calculations aside and looking at pure aesthetics, I'm actually running 245/35/19 and 285/30/19. Been on that for about 3 months with no major issues and in fact correlating against an external GPS unit, the speedo is even more accurate now compared to stock which used to show faster speed than actual.

 

[Static369]

Re: Tyre Profile: 235/35/R19 + 265/30/R19 or 235/40/R19 + 265/35/R19

Sorry to dig up an old thread. I'm driving an E90 320i. The car came with 19inch breyton rims. F235/35 R265/30.

It's not very comfortable when driving on bumpy roads and they're not run flats. I'm looking for comfort. Any suggestions by the more experienced drivers here? Thank you in advanced.

 

[totoseow]

Re: Tyre Profile: 235/35/R19 + 265/30/R19 or 235/40/R19 + 265/35/R19

buy 16 inch rims lor..increase profile to 50

 

[Baby1M]

Re: Tyre Profile: 235/35/R19 + 265/30/R19 or 235/40/R19 + 265/35/R19

If 19" with 35s and 30s profile non-rft but not comfortable enough to thy standard on bumpy roads... seriously need to consider the below suggestion which is along the lines of tyre size & profile as used by taxi.

Seriously if humps and bumps are not meant to be uncomfortable... then i dont know why they are called bumps or bumpy :thinking: