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B210sleeper, your'e a legend. In the real world, where we encounter rain, dusty roads, mud, hot pavement or concrete, the issue is not quite so clear as it might be for a single purpose race vehicle. Generally speaking, a sizeable improvement will be gained with a relatively modest change in tyre size. 235's on the front & 275's on the rear might look hot, but they would be more grief than they're worth under a small light car.

I ran 185x13x60's on the front of my 1000 sedan & they never ever let me down. They never touched any part of the body either.
The rears, however had a diferent spec to fullfill. I needed a bit more gearing, so the outside diameter was increased to the largest that would successfully fit & work under the rear guards. The rear also has a greater lateral [sideways] load when cornering, so i went for a wider section there too. I tried 195's & eventually settled on 205x60x13's for the rear. This also gave it a nice little rubber rake & the Big 'n' Little look apealed to me as well.
Now these are not the sort of sizes that inpress the racers, or the wannabees, but the air volume in the 60 series tyres allowed a quite acceptable ride quality & these tyres never let me down in the twisties with the power that was available to me with my GX & 5 speed. The beauty of these sizes is that they are readily available in a few diferent brands at VERY reasonable prices.
I absolutely loved that car, so much so that the memory of it is what is driving my KB10 project. I was on a good thing & i'm going to stick with tyre sizes that i know worked well for me, rain, hail or shine.

What is it that old farts say,... everything in moderation? Well, combine that with "Horses for courses" That means, use as much tyre as you need, which may be a lot less that what you would like.