2011 we ran in TTA. The next class up and logical progression would be TTS. It employs the same 8.7:1 modified power/weight ratio; but with unlimited mod options. So there are lots more options and scenarios to build up your car which really helps, but also can really increase the costs to compete.
ST2 is a racegroup, it mirrors the TTS (Time Trials) ruleset. So I could prep and do both orswitch midyear as I work into wheel to wheel racing (w2w) or whatever. Both are 8.7:1 modified ratios.
Here are some example power & weight ratios based on the option of a 245 or 275 tire:
lbs - ST2/245 - ST2/275
3301 - - 418 - - 395
3251 - - 406 - - 387
3201 - - 400 - - 381
3151 - - 391 - - 372
3101 - - 382 - - 364
- The numbers across the top (245/275) are the tire size I'd run. You get more hp for smaller tires - less hp for larger ones. The cutoffs are those numbers and smaller so you run the widest you can.
- The weights are post-race minimums. Meaning if you're going out for 30min you need to carry enough fuel (aka ballast weight) to still make your post-race minimum after the race. Same for the 15min TT session.
- The power numbers are dynojet whp. Torque is not checked.