My source lists all the chassis:
SR-70B:
Chassis #001 Sunbeam Imp 850cc
Chassis #003 Ford Escort 1300cc
Chassis #003 Honda 1147cc
SR-71
Suzuki water-cooled, 2-stroke motorcycle engine
EDIT:
Fred sold Quasars as complete cars, as components with plans, or as engineering drawings only
"This car was built from plans by Jim Matthews of Indiana from whom I bought it. I think he originally raced it as a CSR with a British Ford engine, then converted it to a DSR with the Ocelot-built 750cc Suzuki 2-stroke engine
The car has coil-over suspension, so I believe it is an SR-70B. I do not have a logbook for the car. I don't believe my Quasar has a S/N."
That made it a Quasar SR-70b powered by an Ocelot 750cc Suzuki engine built from plans by Jim Matthews.