I will throw up some Roebling times since it came up for comparison.
1:06s Roebling Road. Slow LMP. (and being begged by the team to not risk it before the 24 hours.. I still wish i had just put a hot one down.. dang rookie driver)
1:12s in a Formula Continental. (track record in the 1:07s)
1:15s Formula ford. (track record is 1:12s)
1:19.5 E-Production Honda CRX. (slicks/175HP naturally aspirated, Track record a high 1:18)
1:23s ITA Honda CRX ( I think the track record is a 21)
1:25.0 Dodge Viper GTS. (should be faster, scared driver
1:25.1 Modded but poorly prepped Evo
1:26.5 Stock Lancer Evo (though, if someone will go find me a stock one to play with, I will beat this now.)
1:28 student's Ferrari 355
1:30.2 DSP Impreza RS
1:30 Neon ACR
1:48 Jeep Grand Cherokee, full of students.
Formula Cars, Sports Racers, and GT/EP/ITS/T1 sub 20s.
ITA/GP/HP/SRF/T2 in the low 20s.
ITB/SSB/SSC/SM/IT7 in the mid 20s.
ITC and the rest high 20s.
I can't think of a auto racing class where the record is over 1:30.
Recently I saw Leh Keen run a 1:20.18 in a bone stock Z06.. he ran a 1:22.6 in an STi with only coilovers/intake/exhaust and OEM tires.
I will venture to say that It wouldn't take R compounds to make an Evo or STi go sub 20s.