Ull get good drop but ull be OK. That 180 is prob at 5krpms and is cold rated. Seeing as most ur driving will be below 3000rpm and once heated up you realistically have if lucky a 100a alt. Also, if ur amp is rated at 1700@ whatever load an is fused for 150-170a you will never actually draw that amount of amps as music is dynamic.
That would soley depend upon the brand of the so called 180 amp alt. If it's a cheapo one, don't bother with it. Have read stories and people have bought HO alts before and they fail in matter of no time.