Heads up racing is exciting for about a year as racers figure out what works. After that it is not too exciting imo. Limit to a t31 or 57 turbine and someone will get 10.50 out of it eventually. It takes ideas, r&d, and $$$ to get it done.
Interesting, what about each year there is always one class for the year, that class is one specific single turbo, run what ya brung, any 78-87 Turbo V6, and TTA's Turbo V6. That way every year it is different and exciting. 2012 can be TE44 specific, next year the 6262 etc.