Aussie346

Hey, I've just joined this forum and have wanted some advice on some more upgrades to my LS1. My car is a 2001 Holden VX SS 6speed, so far it has a twin 2.5 catback exhaust system, pacemaker try-y headers, K&N filter, 232/239 cam at 623 lift and 112LSA, and a tune. I'm on a limited budget but I'm after some ideas on how to get a little more power out of it. Bearing in mind it is my daily driver too. I want bang for buck so as much power as I can for the least amount of money. Advice on horsepower gains from manifold swaps, intakes, etc would be fantastic!!
Thanks!