M/T is likely going to recommend bias for a DOT clutch car, here's the description from their website...

ET STREET® R BIAS
BIAS PLY STREET LEGAL DRAG TIRE
ET Street R bias ply from Mickey Thompson is a D.O.T street legal drag tire with proven race compounds and incredible traction.
D.O.T. approved for street use
Latest ET Drag technology to provide the ultimate traction for clutch applications
Minimal tread void for dry traction

Here's the radial description...

ET STREET® S/S
STREET TIRE FOR THE DRAG STRIP
A street tire that can be driven on the track, the ET Street S/S from Mickey Thompson is a high performance street to strip tire with radial construction.
D.O.T. approved for street use
Equivalent tread void as the ET Street Radial II, redistributed for improved hydroplane resistance while providing plenty of tread contact for excellent dry traction
Proven R2 compound, the same proven compound used on the quickest “drag radials” on the planet provides superior traction at the strip with little or no burnout required
Tubeless construction provides leak-free seal without the expense and hassle of tubes

There's also a cost consideration for bias vs radial...
...ET Street Bias in a 28" size are around $244 - $266 each and require a $75 tube. Add the cost of an extra set of rims if you want radials on the street and bias for the track.
...ET Street Radial in a 28" size are around $229 each, no tubes required.

For the basic $200 difference between the two, you can buy a clutch hit controller for the radials and enjoy superior fuel economy/stability on the street, also better mph/stability/consistency on the track.

Grant