Isn't that a Pro Mazda ? just open the rules to do as you please with in the FA book
that has already started in Texas and other places and THOSE cars a Very inexpensive to buy and run
Most FA cars were designed around the dainty Toyota 1600 engine although the Honda K20 has been put on a swift its a way bigger engine and a lot heavier, BUT more reliable
the 13b's are about 50lbs lighter and also shorter
the Mazda MZR all aluminum engine could be used too