HKS GT2535 (350HP) GT2540 (400HP)
HKS GT-RS (400HP)
HKS GT2835 PRO S (450HP)
All the above will bolt onto stock manifold, and use stock dump pipe (apart from the 2835 but if you buy the kit it will come with the dump pipe).
Will make good power with a aftermarket fuel pump, injectors, afm and ecu