I packed an exhaust crossover / heat riser on a big block V8 with refractory cement once to stop an overheating carburetor problem. Refractory cement is good to 2000 degrees for repairing fire places, Franklin Stoves, etc.

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)