Smyka, you have PM.
liljohn, most of the issue is due to the plastic tub of the JS. Both my RS and FS are pretty 'free' with no extensive work. Could they be more efficient, sure. The side belt pulleys are too small and the centers are too. As is my cars and Dave Ehrlich's are pretty good for efficiency.
Will you be attending the Trans Am Nats next month? I will be there with my E4RS. Stop by and I'll show you everything I've done with my car.
Congrats to Dave on his A main finish at the Carpet Nats. Wish I could have been there to make it two E4s in the main.
Socko