GT500FTW

Hey guys.
I'm getting my car remapped soon. I'm using AEM electronic boost controller. (Tru Boost)
My tuner says I need to set my wastegate to 1psi. He said that I need to do this so it gives me more adjustability and the Tru Boost works better this way.
I have an apexi turbo kit with an internal wastegate.
How do I adjust it to 1psi?

turbomaniac

if you dont have adjustable waste gate you have to buy one or you have to modify yours to a turbo mechanic..

some people use extenal spring to do it also but it is difficult to adjust the right spring

also i dont believe that it must be adjusted to 1 psi. did he tell you 10psi and not 1 psi?

GT500FTW

He definitely told me it was 1psi.
If i set it to 10psi, then the lowest possible pressure would be 10psi.
If i set to 1psi, then the boost controller will be able to control between 1psi and upward.

2000CTRSi

Seems like a lot of room for fluctuation and high duty cycles for the solenoid but ok.

TheShodan

iTrader: (14)

I agree. If you have an internal Garrett or Turbosmart gate, you can't go to 1 psi. We've tuned plenty of cars on wastegate settings of anywhere from 7psi start to higher. But in your case you can't go down to 1psi.

The true-boost is really an in-cabin manual controller that goes by duty cycle only. no "gain" feature or anything of that sort, so yes, it works well, but it won't work "better" starting off at 1psi either way.

wantboost

iTrader: (2)

You can simply take your actuator, cut it in the middle and thread both halves (one right hand thread, one left hand) and use a piece of internally threaded hexagonal or round stock to adjust pressure.

what turbo are you using? I might have an adjustable actuator

TheShodan

iTrader: (14)

That's very risky, because even with that rod actuation, it can't go THAT low. Most actuators are adjustable, its just a matter of the range.

wantboost

iTrader: (2)

True, he can't go below whatever the spring is but it's nice to have to adjust preload.

with my Sr20 I threaded the rod on the actuator to go from 7 to 14psi since I didn't feel like I needed a boost controller with the stock turbo. I also used a t3 based actuator with a slightly larger diaphragm for better control.

GT500FTW

I was doing a bit more searching. A couple of guys said to install a second spring. With a washer on the outside of the actuator. This would effectively work as an equilizer spring that will reduce the effect of the spring in the actuator.
The second spring goes over the rod... And of you thread the rod, you can basically adjust the boost.
What do you think?

TheShodan

iTrader: (14)

I say your tuner needs to learn to partial throttle tune to positive pressure like the rest of the world. No one else uses 1 psi springs

turbomaniac

i allready told you my opinion for external spring.

it would be stupid to use external spring if your actuator is adjustable

xile6

Your tuner is very stupid and i wouldnt let him touch my car.

YOu cant turn your psi down that low. Plus there is no need to.
All you need to do is change your inside spring to the lowest boost pressure you want to run.

then the boost controller will p the pressure from there. It will either bleed it off, pulse the line or hold pressures on top.
doing so you will be able to run a higher psi.
Once your work with the boost controller and get a feel for it. You can map the setting into a chart.

x amount of gain = x amount of psi.