I go back and forth on this issue.
As much as I would love to have 22 cars fight without remorse for other teammates I don\'t think it will ever happen.
These teams spend millions of dollars in R&D Engineering, They put the most advanced car on the track every year. Thats why they unveil them every spring with the new advancements in engines and aerodynamics. Exhaust the air jacks everything changes every year for the "good" Well funded teams.
The teams risk to much money having their own teammates battling it out week in and week out to be worth the teams money. Besides if they touch they both lose.
Nascar, Cart and IRL mandate sameness, thus the very close racing. Formula One needs some improvements to appeal to the USA, but it a Euro sport that loves the compentition between automakers as well as drivers. Nascar track this, but as soon as a car gets drastically better then the others they add wind resistence or raise the cars height to level the playing field.
Thats the thing teams like Arrow and Minardi and great cars but the technology is 1-2 years old, there are the baby in the family and get the hand me downs. Thus the Cosworth engine. Asiatech for Minardi is well funded, but only to buy last years engines and mod them to get more power out of the years new advances. They are always better by the end of the year.