When I rev the car it cuts at 5-5500 RPM, I had someone tell me my car I recently purchased has a 2 step. What do I do with this thing, and what does it exactly do? Car is a 5 speed 1998 GST with holset hx-35 turbo and cams, straight pipe, theres no power until 4200 rpms when the turbo kicks in.

Jeff D Desantis said:

When I rev the car it cuts at 5-5500 RPM, I had someone tell me my car I recently purchased has a 2 step. What do I do with this thing, and what does it exactly do? Car is a 5 speed 1998 GST with holset hx-35 turbo and cams, straight pipe, theres no power until 4200 rpms when the turbo kicks in.

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If you hold down the throttle, does it keep bouncing off of 5k rpm? If so, yes your car has two-step. Two-step is what people use to spool up the turbo during a launch. It's usually a set value that people test on their cars to see which two-step value will give them the most grip and ultimately the better launch.

HX-35 is a decently big turbo. Bigger turbos spool later but generate more airflow. Our cars are pretty lame before the turbo kicks in, so don't be surprised at underwhelming power at lower-rpm.

I bet it needs a tune too. It should spool before that but it depends on the hotside setup and possibly the tune. What engine management system is in the car?

Yes 5-5500 K it bounces off. Not sure what engine management system the car has, but there is a switch in the car that turns on a fan (broken) and an aem fuel meter it looks like. Yes I agree 4200 seems very late for the turbo to be kicking in. There's also a cut in power between 3-4200 rpm like theres a disconnection between the turbo and engine before the turbo really kicks in. The car wants to pull to the side as well when the turbo kicks in. Maybe its that powerful? I think theres an exhaust leak. My first upgrade is going to be full exhaust from turbo back. I think the straight pipe on the car is old/not secure anymore.

Sounds like it needs a tune. That fuel meter is likely an air/fuel ratio gauge. The pulling to the side is likely torque steer, basically your power is wanting to pull you to the side of the road. (GSTs have unequal CVs right?)

Not sure. Any tips bringing it to a specialty place for dsms? I looked at prices for a tune and its 500? That seems a little high, do they just hook the car up to the computer and measure air/fuel ratios? What exactly is the 500 getting me, seems really high for just a service and no parts included.

I forgot to mention the car came with the power steering eliminated

I'm not familiar with New York so I'll save recommending places for somebody else. Frankly if you can figure out if you have a tune-able ECU like ECMlink, you can tune it yourself. There are tons of online resources, given your inexperience, I would highly recommend to take your time, and research how to tune it properly. There are enough videos, forums, and articles to get you there, you just need the commitment. This saves you from spending $500 or whatever to get your car tuned whenever you upgrade something.

If you pay for a tune, they will take as much information about the car as they can, and put a tune in your car. Pretty simple. $500 seems on the high side but still makes sense.

PS (power steering) deletes were a popular mod in the early 2000s for DSMs. PS works off the crank, and in-turn hinders power. I'm not really sure how much power (pretty sure not much), but it's the same reason people delete their ACs.

Thanks for the info! Yeah the gain in horsepower is def not worth eliminating the power steering Especially when you are backing up in a parking lot or your driveway. Not fun

Take the ecu apart