I have a 1992 180sx SR20 red top and I want to get it to around 400HP. What parts would I need?

Welcome to the forum.
Congrats on getting your car, please post some pics.

So I'm going to give you a little bit of unsolicited advice because you need it.
This is the same advice I would give any young guy regardless of who it is.
That car weighs around 2800lbs and has like 200hp, maybe a little more or less.
It's plenty to get you in trouble.


What I recommend is doing some track days with it.
Put new tires on it, put new brake pads and flush your brake fluid.
Make sure your engine oil, coolant, transmission oil, rear differential oil, and powersteering fluid are all replaced and at the proper levels.

Go to a track night in america event.
Spend some time in your car and learn it's limits.
You will find out soon enough where you want to modify it.
You'll want better wheels/tires, brakes, suspension and some gauges/electronics.

There's a phrase out there that goes like "Make your car stop, turn and go"
The tires/brakes make it stop better.
The suspension will make it turn better. (There's a lot of parts that I am just lumping together by saying "suspension")
Then FINALLY, you want more power. Power is useless if you can't control it.
Building a car is all about the whole package. It's about doing things in an order that makes sense logically.
If I snapped my fingers and your sr20 magically is at 400 hp, I guarantee you that it will result in a crash.
The stock180sx isn't designed for 400hp. It's designed for 200hp at the crank which is like 160 at the wheel.


Please don't make the same mistakes I did.
Don't do dumb stuff on the street.
Don't hurt yourself/others or potentially worse.
Don't spend a lot of your youth trying to fix things that shouldn't have broken in the first place.
For the love of God don't overbuild your car either.
The point is that you want to drive it.

I've known plenty skilled drivers who've wrecked cars on the street. You think it won't happen to you, until it does and your dream car is wrapped around a phone pole.

If you have already have an SR in the car, you have nearly the power to weight ratio of an American V8 car.

The absolute most beneficial upgrades to your driving enjoyment will be a limited slip differential. I recommend a "1.5" mechanical type. "2 way" is very exciting in normal street use, too exciting (it locks up when you accelerate or lift off the throttle and any curve where you need to slow down, like off ramps, is a fight to not spin). I prefer Cusco. And have had no trouble from Kaaz either.

Budget options include viscous lsd, if those are even still available from J30s, at junk yards.

A set of adjustable coilovers that can lower the ride height while allowing you to adjust preload so you don't do that "my car is TOO low vertical wobble" is also a game changer. I'm using a set from Ksport that initially I was wary of for street use because the spring rates seem high, but it's been surprisingly livable except on the worst roads.

Add in a rear sway bar and rear strut tower bar, strut bar is a pain and not necessary, to cut out the S13s tendency towards understeer or a heavy nose.

And, as the other guy said, upgraded brakes are a smart idea. You're already putting down more power than the stock brakes were designed for. Brake kits aren't cheap, but better brakes make a noticeable difference. You'll need to be careful of wheel fitment, but 300zx or R32, 33 Skyline brakes are budget options.

400 whp out of the SR is going to be very expensive if you want it reliable. You need a full rebuild with forged parts, custom fuel tuning by someone who knows what they're doing. The crank, cams, pistons, and rods will probably cost as much as everything else I've talked about, if not actually more.
I think Tomei had a 400 hp crate engine years ago that was around $10k.

400 is also a silly power goal for how light the car is. Start with a differential, and coilovers.

I have an RB making right at 400whp. All the other stuff I mentioned made the car more fun to drive and more drift worthy for way less money.