Huffer

Alright you lot, get your thinking caps on.

I've got an MY98 Impreza - 2L non-turbo.

I'm wanting to make some modifications to increase the power without sacrificing fuel-economy.

Give me your top five modifications (in order of cost-effectiveness). And please no suggestions of adding a turbo - it's not going to happen!

Huffer

come on you lot! I know there's some bright sparks out there who can give me advice on upping my power!

Absolute Shower

As with all 4 stroke motors, I'd suggest a performance filter, change of backbox (or system) and a chip (for fuel and ignition advance). Do all of them, since it will help the engine to injest more air/fuel and increase gas exit = more power.

No idea re cost or power for the non-turbo though. Best to look on the net.