Could use help with a rather odd issue

hermit

You know, I think I came across a discussion about this on some thread a long time ago. Some people were saying that more width = more tread on ground = more traction. While others were opposing that idea. I know a very small portion of the tire actually touches the ground. And I thought the only way to increase that amount was through width. Though it may be just a small addition.

I didn't know that wider tires dissipate heat better. If nothing else, that alone is worth going wider. Aside from a better more aggressive look, in my opinion.

But taking it to a simple extreme, just a thought. So, say I take tires the width most Prius's use but a high performance tire like the RE-11. Then I take the Nismo's stock tire size in the RE-11. Let's just say both 19" and compare on same exact 370Z. I would think all I would do with the prius size is spin all day. It's a confusing concept to think other-wise. However, I am an opened mind and like to learn.

MacCool

Physics is physics. These friction concepts have been known since the time of Coulomb (18th century). You can prove the concept mathematically yourself using the formula I included above. Ffind the variable that represents contact area. (you can't....it doesn't exist)

Contact area has nothing to do with friction, and increasing contact area won't increase your traction. Now, if you're going to track the car, then you'll want wider tires for the same reason race cars use wider tires...to keep them from getting greasy when you really push them on the track. I'd be pretty surprised if more than a few people here on this forum had the skill to push their Z, even an FI Z, that hard on the track where the difference between 325's and 275's would affect your ability to run the car.

hermit

I get it, it was just a talking point. Either-way, this helps in my decision. Currently I have 245/35 and 275/35, and I don't care to much for that "stretched" look as it has been stated by others. On the other hand I don't want to make the steering overly heavy. Which is my chief concern with going very wide. The extra heat dissipation will be a nice addition. But, more DD with occasional tracks for the moment. A bit more aggressive look is a plus, but not my intention (opinion). My biggest concern being the protection of the wheels really.

At first I was all in on the RE-11's. But, as this thread went on I've heard more about the S-04. As well I have come by more threads on it. I'm still indecisive between those two. But tire rack has a decent deal going on the S-04, which is swaying me that direction. Plus, it's Wisconsin I live in, our weather is just stupid sometimes. I always have my Xterra around for that though.

As far as size, based on everyone's help and suggestions. I think choosing a somewhat of a middle ground is best. I see what I have currently for size and I hate it to no end, I can post pics if anyone wants them. Grant it these tires are just crap. But, I do want wider, I just don't want to end up wider than what I am looking for. So, call it a stepping stone. I'll move up and when it comes time for new tires, if I want wider I'll go more wide at that time.

I'm thinking 265/35 front and either 285/35 or 305/30 rear.

Red__Zed

Coulomb's model hasn't been considered an accurate representation for pneumatic tires since...well...ever. His model works well for "hard" solids, not so much for sticky, deformative surfaces.

Contact area definitely does matter for systems like a tire on pavement. We've already establish that pretty clearly in the other threads where this has come up - both adhesive and deflective components rely on surface area.

https://en.wikipedia.org/wiki/Fricti..._Coulomb_model