Loose, dry and dusty I think. Probably will not be maintained too well. I'll check out the Blockade..
Dan this is one of those questions were the more information the better.
Hard pack or loss, does it brake up or brake down. Dusty or not. Wet/dry, does it hold moisture. Even track temp. But we won't go that far.
If it's a hard pack don't brake up. Id go Calipers, blackage, cityblock maybe even a tire like electron or a prositron. Depending on what the track feels like and what in mixed in with the track.
If the track starts to brake up, is wet or holes moisture I'll drop calipers fast they don't like heavy build up and clog up. A tire like a prositron or an electron won't see that unless there's a lot of clay and it's very wet.
If it's brake up fast, Dusty and any thing but packed. Water adds traction but now everything clogs. Id be looking for a wide space between lugs not so much deep lugs. Cityblock would you the closet spaceed I'd use. I would however probably start with gladators and see how they clean, might go to Schumacher spiral pins if I'm having issues, As they clean out superb. My perfered tire at globes, as it's a sand trap clogs everything.
Then if it's high traction wet clay not puddle wet. I'd look for a smooth tire like primes. If it dust up and dry up may some like a inversion.
Well to cut this short. What I'm trying to get at. Is with out seeing the track in person and seeing it in race condition we could be shooting you the wrong tire and depending on how the track changes throw out the day the tire to start with maybe a junk tire by mains.
Now if you tell use the track name I'm Shure one of us would have ran there. And can shot you better. Also often the track owner know what tires are race day perfered. Or Even ask the other racers.
Sorry for the long post, and I'm half asleep if it not understand able.