What does HO stand for?

[Mavrick]

also the regular 302 has a 2 bolt main the ho has a 4 or maybe thats the differnce between the ho and cobra

Bad info buddy... boss 302's have 4 bolt mains... maybe SVO blocks do as well but im not sure on that.

HO is just "high output" and it means that its the performance 302 rather than the regular 302 (like in crown vics etc).