No. 6 volt systems will spin over an engine just as fast as any 12v system.

Your problem is most likely found in your wiring and wiring connections.

Your battery cables MUST be 00 gauge - basically welding cable. Your grounds MUST be perfect. Disconnect the ground wire from the the starter to the frame and wire brush the connections. Swap the woven belt for a 00 gauge cable. Make sure the battery is fully charged to ~6.3-6.5 volts


1950 Chevrolet 3100 (Ol' Roy)

1939 Packard Standard Eight Coupe (The Phantom) | 1956 Cadillac Coupe de Ville (The Bismarck) | 1964 Ford Galaxie 500 coupe |1966 Ford Mustang (Little Red) | 1969 Pontiac GTO (The Dishpit) I 1979 Ford F-100 | 1976 Ford F-150 (Big Red) | 1995 Ford F-150 (Newt)