The days of being competitive at B'ville with a hot rod are almost gone----you are going to have to have a serious "RACE CAR", my lakester RATICAL was a homemade hot rod BEAST---if I ever want to beat The Hammond's beauty---I am going to have to have an all out race car, with a race motor. I dont mean that I have to have it all built by porfessionals---I am just going to have to have a more professional approach.
This is especially true if you want to run speeds where AERO is almost everything.
San Diego to Maine is a lot less hassle than trying to Build ANYTHING that maybe competitive--- maybe even a 500 CC turbo bike. If you want to run a BBC and you can buy a Complete car that has had a BBC, goes straight and has competitive aero, you can tweak and change and make it yours.
my opinion
YMMV