Sorry for long delay. Only 1/4 mile hit: drove through convertor at 200' and basically was cruising the rest of way on rev limiter. Spark plug hole repair blew, so we lost a plug at 1000'. Now getting ready for Indy points meet.
That is bad ***! A guy at my local track has a street driven 67 Chevy II wagon with a twin turbo injected big block that runs 7.50's in the quarter. I want to do a turbo build.