So i bought a nissan ps13 with an 1uzfe engine. Due to my budget at this point and the need of driving i'm asking here what i can do to this engine without adding a turbo or etc to get the most horsepowers out of it. And by that, how many HP can i get out of it without adding such things? New intake manifold? New exhaust manifold + system? anything else?
Replace all the plugs, leads, caps and arms, flowmeter with brand new items and clean the injectors and you may return to near stock power. Other than, without headers, airbox etc you'll gain absolutely fuck all. NA tuning is very expensive
If you haven't already, remove the AC compressor and why not lose the PS while you're there. Otherwise, good luck getting power out of it without throwing money at it. I do need to ask though, why do you need more power? It's an S13 FGS. It doesn't weigh a tonne and would have ~250bhp and lb/ft of torque...that will be adequate but I'm guessing that isn't the issue. The most cost effective thing you could do would be to make a cheap pair of log manifolds (or buy them) mount a cheap HX40 or even a HX/Y35 with a larger exhaust housing on it, get bigger injectors and a rising rate fuel regulator and it will run 7psi boost on the standard ECU.
This. and further more if you go and stick a full exhaust system on it you'll only end up ripping most of it off later to shove a turbo on.
You could spend a fortune getting head work done, new cams etc etc for mild gains, then whatever ecu tuning is required to optimise it. Depends what your budget is and how adamant you are about staying n/a. But as others say, n/a tuning is very expensive for poor gains.
