Aspect ratio and width for street and track

[dcozzi]

I am looking at tires to fill the tubbed rear wheel well of my '70.

The front end will be tubular A-arms, splined 3 piece sway and coil overs.
The rear will be a Lateral Dynamics 3-Link with coil overs.

For straight line traction, you need width. You need sidewall strength and stiffness for handling. You need enough sidewall to take up bumps and the occasional holes in the road so you do not destroy the wheels.

I am looking at 17" - 315/35/17R, 275/40/17F
18" - 335/30/18R, 275/40/17F

The question is: How wide and with what aspect ratio is the limit for severe track use as well as street driving?

What are your ideas on sidewall practicality vs. handling vs. straight line traction vs. streetability?

[6'9"Witha69]

You want your cake and eat it too. Not gonna happen. There are sacrifices to make based on goals and priorities.

Road racing requires good straight line as well, like coming out of a corner into a front/back stretch. I think what you have selected will work. Compund will make a huge difference in traction both ways. The sacrifice will be ride comfort.

[dcozzi]

Everyone likes the look and traction of a tire that is as wide as they can fit into the wheelwell.

I always wondered what happens when you start getting into the realms of ultra low aspect, super wide tires. (ie. 355/20/19). Super expensive, limited brands and compounds. They just do not seem to be worth it.

They look real cool. The ride quality is poor and risk of damage is very high. Do they really add much if anything to handling as opposed to a 30 or 40 series tire?

6'9"Witha69 - It looks like you have been down this road before. I totally agree about wanting it all. It's a terrible sickness we all seem to have. Isn't it great! I have been looking into compounds, brands and application specific tires. Your options get more limited the bigger you go. Seems to me, the choices are pretty good for the sizes I have chosen so far.