Yessir, you certainly did. :thumbsup: We agree on that!

The reason I started this post is I was talking with a Race Car Chassis builder. Most of the cars he build are for long tracks not short tracks like autocross at Good Guys Events.

Long story short he is building of all things an s10 pick for a gentleman that has a 250,000 porsche race car. The tire size he is putting on the truck is 275 front and 295 rear. Engine is a 383, forgot to look at the trans. He is confident that with the suspension set up and scratch built chassis it will handle every bit as good as the owners Porsche race car if not better.

They are building it for fun to beat other high end cars. Nothing like getting spanked by a little S10 pick up. When I asked him why not go bigger he kinda laughed and said ,"Son bigger isn't alway better"

By the time he was done explaining everything to me it made more sense. I figure since all this guy does is actually build track cars he must know what he's talking about. I remember a VW van that was built with the same philosphy and it surely didn't have big tires

https://www.youtube.com/watch?v=0MLCuaPdPew

of course, purpose build and factored into design a smaller tire is fine. 275/295 isn't really considered small either. its all about balance.

Hi Vince,

I agree but there are some purpose built cars on this site and the others that I lurk on and they are all going bigger is better.

btw - Don't tell Kenny I am thinking about building a road race s10. He might kill me.

Is the question diameter or width?
 

I am also pondering a similar question. Or I think it is similar. I am questioning the gain or lack of by increasing width.

Tire size dictates a lot on a build so I am agonizing over the rear tire size. Diameter is locked in to 27 to 28" for me. I want to keep the proportions right for a car with a big back end (1969 Torino fastback). I can fit a 285 40 19 out back and don't even think I need to touch the tubs (I run a shorter 285 40 17 now). If I do a 4 link (copy Jasons DSE install) and tub it then I could go all the way to 345.

I plan on taking the car to track day events and maybe some open road events.

I would think proper ear suspension set up makes the most difference along with track width. With DOT rubber how much lateral grip am I giving up (any really) with a smaller diameter tire 285 vs 345?

In an overly simplified scenario with all things being equal. When you increase tire size but maintain overall track width does it really make that much of a difference?