I was reading on TireRack today (seems like I'm always on that site) comparing the lap times of the different tires. From the tests run on the BMW 330CI, on Max Performance and Ultra High performance tires, the lap times are nearly identical. Both the Max and Ultra tires are capable of hitting 29-30 seconds on the lap times. Only a fraction of a second separates the two. So what is the advantage of getting the Max summer tires when the Ultra tires (read: cheaper) seemingly circle the track in the same amount of time?

Currently I'm using the Avon Tech M500's on my S, and am wondering if I will really notice a difference in handling and cornering speed, if I upgrade to the Bridgestone Potenza S03's.

For example

Avon M500 produced these numbers on the TireRack course in the 300CI
Slalom time dry: 4.20s
Slalom time wet: 4.59s

Lap time dry: 29.90s
Lap time wet: 32.28s

Dry skidpad: .95g

Bridgestone Potenza RE750
Slalom time dry: 4.20s
Slalom time wet: 4.62s

Lap time dry: 30.00s
Lap time wet: 32.62s

Dry skidpad: .94g

Bridgestone Potenza S-03 PP
Slalom time dry: 4.18s
Slalom time wet: 4.61s

Lap time dry: 29.79s
Lap time wet: 32.05s

Dry skidpad: .97g


Compare the times... the S-03 is only marginally better. So what gives? I would like to upgrade to Max performance tires but after reading this info, it doesn't seem like I can justify it.

Can Jim or anyone shed some light into this?

 

Those performance differences seem like a lot to me.

.03 g more on the skip pad and .2-.5 sec faster lap times with just tires.

I wouldn't dump perfectly good tires to upgrade but if yours are worn and you want to maybe do a track day or maybe try out autox its worth it.

 

Also, keep in mind that those times are for a very short 30 second course. Take those differences and expand them to a 1 or 2 minute lap and it adds up. Whether it's worth it or not is entirely a subjective decision.

 

True. Didn't take into consideration that the course is a fairly short one. So I guess .2-.5 seconds on a course that is 30 seconds is more dramatic than on one that is 2 minutes.