ChevyRyda99LS1

if I add rocker arms underdrive pully and elec waterpump how much do you guys think I will gain from that.

jetlag

iTrader: (32)

I wouldn't change rocker arms. Not sure on the water pump. and my car gained 6rwhp 10trq from an underdrive pulley.

Blk_Ws6

iTrader: (4)

8rwhp from the electric water pump .

180ls1

iTrader: (4)

those three things are really not worth it since you will have do do valvesprings as well. I would bet you would gain 20 at the most. I would throw a small cam in berfor you did those mods, a cam will cost a lot less also and give you better gains.

cdubbzz

iTrader: (11)

I would change out that Slowmaster cat-back first for
something more free flowing like Magnaflow etc.