Changing from 17s to 18s

[96dreamer]

Anyone with decent power swapped from 17s to 18s. Highly considering picking up a set of the new LMR machined face 03 reps in 18s to replace my 17 machined setup. I am concerned about having to go from a 315 35 17 to a 305 35 18 and how that will adversely affect traction. If its going to be that big of a hit to performance ill just forgo the idea.

 

[LS WUT]

It will be just fine. It’s mostly about sidewall honestly. My 305/35/18 mickeys did amazing. I used to have 315/35/17 on my cobra R reps. I hook more with the 305.

 

[Bullitt1448]

There is less than 1/2 an inch difference, I hope your not counting on that 1/2 inch to give you the traction you need. I doubt you would notice the difference

 

[DSG2003Mach1]

There is less than 1/2 an inch difference, I hope your not counting on that 1/2 inch to give you the traction you need. I doubt you would notice the difference

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I dunno if they have the size you need or not but wouldn't be the end of the world to up the rolling diameter a hair, just dont get too far away from the front so it doesn't screw with the abs

 

[Ians_cobra]

I think the difference wouldn't be really noticeable. According to the visual tire comparison 315/35/17 are just 10mm wider than new 18s, so the traction wouldn't be compromised (o you can get a set some tires with stickier tread).

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The overal wheel diameter of the 305/35/18 is 3/4" bigger than 315/35/17.
Theoretically a bigger wheel reduces the acceleration and mileage, but may increase the top speed. The speedo will be slightly off...but again I believe it would hardly be noticeable, so I'd hit that...for now I run 17s too.

 

[Tabres]

My experience, you'll notice the size/weight difference under braking more than anything else.

Same tires, comparably sized, I've never noticed any traction differences between 17s and 18s. The boost ramp isn't super aggressive on the tune I typically run around on, though.