Bob,
Doing a little math and assuming that the salt coefficient of friction the maximum amount of power that you could put down at 190 mph and 2000 lbs on the drive wheels is about 400 HP, the salt was pretty good so if you assume that the coefficient of friction was .5 it would be 500 HP. So with 900 HP available it is probably right that you were spinning the tires. If you only added weight to increase traction then you would need to have a calculated rear wheel weight of 3500-4000 lbs. This would be at 190 mph and in reality you want to go 237. So doing a little more basic calculations and making the assumption that to go 190 mph your car needs 400 applied HPs and that aero drag represents 85% of the total drag (the rest being rolling resistance) at 237 mph you will need 660 HP to over come aero drag and 100 HP to overcome rolling resistance it certainly looks like you could be a record challenger. You really need to do something to increase rear axle weight to provide more forward force. A glance at the Gas Coupe rules looks like any type of aero down force, i.e. rear wing or spolier, that is not stock is not permitted so ballast looks like your only choice.
You hear Bonneville called the " long white dyno" and this a great example, at 190 mph Bob's car starts to spin the tires (we assume) using that speed and the estimate of the salt coefficient of friction we can calculate the horsepower to attain that speed, 400 in Bob's case, and if we had the frontal area we could calculate a pretty good estimate of the coefficient of drag. Obviously all of these numbers rely on "best guesses" like what the salt's coefficient of friction but it does give us at least some idea of what the potential of Bob's car could be if he can get traction. I have not taken into account such things as drive line efficiency or reduced air density because of the altitude, temperature etc.
Rex