Quote Originally Posted by Stan Reid View Post
It was expensive but they were also running Offys at the time which weren't cheap either. As I understand it, they just put the left cylinder head on the right bank and vice versa so the exhaust ports were on the down side. I imagine they swapped pistons as well since I doubt that they were symmetrical. I actually saw one race in a Sprint Car on the half mile track at Knoxville, IL with Aldo Andretti (Mario's twin brother) driving. I think most of the front engine development happened after A.J. Foyt took over production of the powerplant.
Looking at references I note that USAC dropped dirt track races from their championship in 1971. There were many races still run by other sanctioning bodies, but would these tend to feature less sophisticated Ford motors, or did the Indy engines remain popular for some years?