Hi all!
In the process of converting car to RWD and lowering to GT-2 specs with PSS10 coilovers.
My rear PS2 (stock sizes) need replacing before TX Mile. Car is also a DD but Iam very liberal on putting up with loss of creature comfort to be fast. I do care about car being safe on the street however.

Should I replace with:
1. PS2 315/30+235/40
2. PS cups (only avail in OEM sizes)
3. Toyo R888 315/30+235/40
4. Other - please explain

I'd like to know this too, however, I'm pretty sure that you DON'T want any kind of sticky race or drag tire as they are not designed for extended periods of acceleration and can come apart. When I ran my bike I was told to use a very hard compound tire. I was shown pictures of drag radials that had shredded their skin...

I'm thinking a regular street tire is sufficient, as you don't need the traction to launch and won't likely spin over 150mph, except for the VERY high HP guys...

Agreed.
I'd say the ps2's would work or any tire rating of (y) 186mph specification.
ps cups also have the same (y) rating, so a bit stickier, too.