Thanks everyone for the input. It looks like it's I am going with the Firestones. Why? 1. price, m&b on the car $80.00 ea. 2. I had a set of Firehawk SZ50s on a 91' a few years ago and I really liked them, very little noise and great in the rain. Yes I drive my vettes in the rain, I've 5 of them and they have all been in the rain and snow.

 

I have run the BFG radial T/A for years and generally been very happy...However my 255/60/15's rub at full lock and deep turns with a dip. My rears are about shot (interesting how they never seem to last as long) I'm going to rotate fronts to rear and put 235/60/15 on the front. Theses are all on the 15x8in rally wheels.

 

I swapped from 225/70-15 to 255-60 BFG's on my '81. On badly grooved roads the car tends to follow the grooves, but the road surface has to be particularly bad for it to need any real effort to correct it. It also did this with the 225/70's but the wider tires have made it worse. I haven't noticed any problems with the rear, it mainly seems to be the front tires that track the grooves? This is a problem on very bad surfaces, "normal" bad surfaces(!) aren't a problem. This isn't very clear! OK, the one stretch of road that causes the Vette problems that need a conscious effort to correct causes my m/cycle to completely ignore my steering inputs! At 80mph the bike gets stuck in the ruts & randomly follows them (this is not fun) needing a lot of effort to keep it in a straight line. The Vette at 80mph feels twitchy & darts slightly side to side but is a lot easier to correct than the bike. Driving the Vette on that stretch of road is at worst annoying, on the bike it can be terrifying (esp. if a 44' articulated lorry is alongside weaving from side to side due to the surface, an outside lane hogger is on my other side & the obligatory BMW 3 series is 5' off my rear light ). Hopefully that gives an indication of just how bad the road is before the Vette starts needing a conscious effort to correct it. I get far more unwanted directional change from bump steer than from the wide tires tracking rough surfaces. On normal & good surfaces I think the BFG's 255/60s are far, far better than the 225/70's that were on there, so on balance I prefer them. They also look good! After trying different pressures I've found that 35psi gives pretty good control on bad roads. Lower pressures seemed to exagerate the problem.
The stretch of road I'm talking about is infamous in this area & a lot of people complain of vague handling in various cars on it, from grocery getters to Chimeras, so it's not just my Vette that suffers. One C3 owner I've spoken to had fitted 225/60's on the back but had kept 225/70's on the front (due to clearance issues) & said that it felt pretty good on bad surfaces as the thinner front tires were less prone to track the ruts.

Ignore all the above! The 255/60's do cause a more pronounced vagueness on rutted roads than you're already getting with the 225's, but, unless you drive on abysmal roads, it won't be a problem.