sidewall effects on body roll?

[lbluecamaro69]

I want the stock look of the 15" rally wheels with sidewall tires on my 69 camaro, and the 15x7s will clear my disc brakes all the way around.I plan on making some suspension mods like a dse tubular sway bar, tall ball joints& tie rod ends and such. I'm just curious about the effects of having a larger sidewalled tire on body roll and handling. Will it not make a difference if I have the big sway bar and stiffer springs( and maybe some varishocks later down the road to replace the over the counter ones)? I plan on maybe autoxing at car craft next summer but other than that only street use. input would be appreciated thanks

[astroracer]

Tall sidewalls will have a huge effect on cornering. Sidewall flex will not be offset by huge swaybars and stiffer springs. All you are doing is creating a very harsh ride trying to compensate. If you want to autocross build the chassis to work with some 17's or 18's and use the 15's for street only. Going from 15's to 17's on my truck made such a huge difference in response time I couldn't believe it...
Mark

[Peter Mc Mahon]

I don't know the size of tire that they use, but Formual 1 looks like somr huge side walls. Do they have crazy high air pressure or something?

[astroracer]

Not a good apples to apples comparison to a "street" tire... The Pirelli's are race only and I have found no info on sidewall firmness or number of belts used to build the sidewalls. I doubt Pirelli wants this to be common knowledge. You also have to consider the F1 cars are a lot lighter then an everyday Camaro or Mustang so, looking at that as a "they do it why can't I" scenario isn't good either.
Mark

[lbluecamaro69]

Thanks Mark. I might have to rent/borrow some 17s or 18s for auto x then

[Paul Huryk]

The typical car with 26" (or 27") tall tires hits a sweet spot of sidewall height vs ride vs tire spring rate at the 17" to 18" wheel diameter as others have mentioned.

Formula 1 car have a huge sidewall to act as a spring and also absorb all the downforce that the cars produce. They can pull 3g+, which in effect makes them weigh as much as a modern full size sedan.

[olason]

if you are able to find the K (stiffness) of the sidewall at certain pressures you could have an idea. I suspect certain compounds would be stiffer.

For Formula SAE Hoosier gave this information out. Maybe contacting the company they could lead you to the correct compound then give you a stiffness chart for that tire.