Hope im in the righ place here. To start with my setup..it's a 406ci sb with Eagle internal's,10:1 compression, Pro-Topline heads 200cc runner 2.02/1.60 ported and bowl blended, 1.5 Harland Sharp roller rockers,Comp Cams solid roller 280/286 .570/.576,Fluid balancer,Team G intake and 670 Holley carb.
Motor seems very strong (still breaking it in) but i was thinking of changing pulleys. How much if any REAL power increase could i see from going to a set of aluminum pulley's? I know these old pulley's are very heavy and since i have no air or power steering i could go with single groove pulley's. Any replies appreciated.

 

Consider a March serpantine ( muli groove) conversion. You'll never throw a belt and the multi groove belts run more efficiently. It looks cool and the kit can be had underdriven or with an overdriven waterpump.