Hey,

With 215/55R17 you have tons of choice. From my price table I got the following options.

Kumho Ecsta PS31 215/55R17 313
Toyo Nano Energy NE03 215/55R17 352
Goodyear EfficientGrip 215/55R17 370
Continental UC6 215/55R17 400
Continental Max Contact 6 215/55R17 430
Yokohama Advan Fleva V701 215/55R17 440
Goodyear Eagle F1 Sport 215/55R17 441
Michelin Primacy 4st 215/55R17 528
Michelin Pilot Sport 4 215/55R17 565

From what you said, I deduce that your main requirements are mileage and handling?

I would recommend Primacy 4st due to its higher UTQG treadwear rating (340 vs 320-PS4) and better overall performance

You can check out the head to head comparison here

Hey there

Interesting point you have here. I will try to explain from a tire engineer point of view & what are the possible risk and so on.

Current situation: You have a damage on the sidewall, I can see from the picture that it has not penetrate the carcass if not you will see some textile material.

Do I need a new tire? : This depends on your risk appetite. Right now the sidewall rubber which is suppose to protect your sidewall is gone. So this is actually in the flexing area of the tire. What this means is that your tire is constantly being compress and elongate in this area. Around 80-90% of the stresses actually occurs in this area during any "excitation" of the tire. It seems that with your current driving style, the tire is still able to withstand the flexing and function as normal. However now as your tire is longer protected, any foreign object at high speed would be able to penetrate your sidewall easily.

Recommendations: From the test I have seen, it is advisable to change the tire. If I were you I would do it as safety is at stake here. If you have a bigger risk appetite, please check your tire for any pressure lost regularly (every 7 days). Also please take note if there is any crack propagation happening due to the flexing. Sidewall damage at high speed is not as fatal as tread separation but it could be equally as fatal.

Thanks!

Hey,

With 235/50R18 you have a decent choice. From my price table I got the following options.

Kumho Ecsta PS31 235/50R18 468
Yokohama Advan Fleva V701 235/50R18 538
Continental UC6 235/50R18 540
Continental Max Contact 6 235/50R18 550
Michelin Primacy 4st 235/50R18 730

What are your main requirements? Are you happy with MC6?

Looking at the options, if you have the budget, I would defeintely recommend Primacy 4st due to its outstanding wet performances.
I made a comparison between Primacy 4st vs MC6 quite sometime ago here