Best wheel alignment?

[BlueBull]

I made recently a wheel alignment to GM factory settings. The car (a camaro 1967) is not modified in any way.

Now my problem. The car is still sensitive to wind and especially the quality on the pavement. Suddenly the car can go left or right depending on this things. When the conditions are the best, the car is great to drive but this worries me.

I have 18" rims with 235/40 tires with low and close to square profile why I suspect they may be a major part in this problem.

I have at theory that a change in the wheel geometry by increase or decrease the toe-in may help. Now, in which way will I reach the best results? Previous experience I have from this is that more toe-in made the car more stable, but that was a complete different car.

Any advice is very much appriciated.

[BlueBull]

I'm convinced I diden't describe my problem clear enough. Anyhow, I tried to make small changes on the toe-in setting and evaluated the results.

First I tried to go for a toe-out close to zero with the result the car became more unstable. Then I set the toe-in to approx. 3/8" (from 1/4") and a recognized a big difference.

Hope this can be of some help in the future.