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I just bought a gts-4 for my younger brother's first car. After driving it for a week or so I'm reluctant to hand the keys over with the car in its current state. From what I've read the stock actuator on the r32 is 10psi and the stock actuator on the r33 is 5psi with the boost solenoid taking it to 7psi. I have a turbo and actuator from an r33 and was planning on swaping the actuators to achieve 5psi until he has some more time on the roads under his belt. Is there anything I'm missing or need to know?

On a side note the cheap looking boost gauge in the car seems to read around 13psi. The car has a separated dump, 3" exhaust and an upgraded SMIC which might account for a slight increase in boost but I wouldn't have thought that much. Maybe the mods coupled with a dodgy gauge is the reason for the higher reading.

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depending on what state you are in it may not even be legal for him to drive it (if he is on his p's).

putting the lower actuator on will lower the boost, however it won't take it down to 5psi. exhaust and intake mods will bump it up a bit.

From my experience, using the stock r33 actuator alone, even with mods, the boost was around 6 psi. With the solenoid, it went up to around 8.5/9.

It is straight swap and a great way to make the car a bit safer while he's learning. It won't make it too slow either if that makes sense. It'll still be faster than most things out there.

Yeah not a bad idea there mate, should work too.

You may not get exactly the same boost level as you would in a 33, however it will give you less boost than a 32 actuator, which is basically the point of why youd be doing it anyway.

you can also take the R33 actuator and elongate the hole by filing it so there is less preload on the spring:)

or if you want to disconnect the rod from the wastegate flap leaving the waste gate open all the time.

an R32 with 5psi is still a very fast car for an inexperienced driver. I can guarantee I would have crashed one if it was my first car.

or if you want to disconnect the rod from the wastegate flap leaving the waste gate open all the time.

Hey thats a good idea. A lot less work than changing the actuators (providing the rod is easy to access) and if its tooo slow then I'll chuck the r33 actuator on. I dont necessarily want to take away all the boost but I guess I'll see how it drives.

Wind the ign timing back 10 degrees. Thatll take power out :laughing-smiley-014:

Probs the easiest and you dont need to take a hell of a lot (i was kidding with -10) to decrease the power considerably. Just watch the engine temperature. Pig to drive tho off boost.

Controlling boost is the best option tho but at least you know you can do something else.

You could make up a restrictor plate for the exhaust, maybe just punch a 2" hole in the restrictor plate and place it somewhere between two joins in the exhaust.

It will still look and sound like a tuff exhuast but the restriction will bring down power considerably + its cheap and easy to reverse.

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