School me on supercharging a 360

rumblefish360 said

For what I understand, you would use a low comp. ratio because your forcing more air in. Upping the cylinder pressure like it has more compresion. So you don't start with a high compresion and add more.

A low ratio for these engines I have seen recomended starting at 8.5-1 and lower. I don't know how high of a static ratio you can start with and then add pressure and/or how much pressure.

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Like most people i didn't filter through the BS in the beginning but I hope this helps.

For comparisons sake, the '94 5.2l magnum in my duster is running the stock rotating assemble about about 10psi with out any problems. The are hyper pistons not forged and about 9.4:1. I know of stock 5.9l magnum rotating assemblies that have been consistently street/track driven at 15psi. Granted these are turbod not S/C'd but the premise is the same.
How much static compression you run will have an opposite effect of how much boost you produce. More compression=less boost and less compression=more boost. There are pros and cons to each.
At a higher compression ration each lb of boost will produce more power than a lb of boost for a lower compression engine. But you're limited to small pressure levels because of risk of detonation
At lower CR though each lb doesn't count for as much you can run much several times more boost than a high CR engine. Obviously the more you compress the air the hotter it will become so cooling the charge will become a large issue as large PSI is reached. Also percentage of power gained per lb will decrease at very high pressures due to flow characteristics and burn efficiencies.