Many V8 engines have a coolant crossover in the intake manifold, that's where coolant flows to get from one side of the engine to the other.

The M-block engines (351C, 351M, 400, 302C in Australia) had a "dry manifold" in that no coolant crossed in the manifold BUT there was an exhaust crossover.

This was to heat up the carb area for quicker warm-ups in the wintertime.

The crossover was throttled (at least on some applications) so as to keep from overheating the manifold & carb. but I understand many people disconnect that apparatus when they replace their exhaust systems and that can cause problems with gas boiling in the carb bowls.

I have an Edelbrock Performer 400 on my 400 (M-block) in my 1981 F350.

To which engine does this "Street Warrior" thing apply?