for any of you running the aem truboost, what is a good set up for the mods that i have in my sig, i really have no idea how i should set it up until i get a reflash in a couple of weeks. if some one can give me some kind of a base guideline as to what duty cycle, spring pressure, etc. to run for now so i wont do any damage to my car. my wide band was reading 10-11 ish under full boost at around 22psi and 14-15 reg driving. keep in mind i still have the stock turbo, and my car has never been flashed.

thanks for the help.

 

anyone?

 

The AEM has 2 basic controls, boost solenoid duty cycle, and wastegate crack pressure or spring pressure. It can store 2 boost profiles, A and B (pump gas 21psi / race gas 25 psi for example).


Duty cycle % - increase this until you hit desired boost. mid 50's will be around 21psi depending on car. Adjust it until you get desired boost. Untuned I wouldnt go beyond stock boost levels. To set this get in 3rd gear and increase until your boost spike is around 21 psi, you can hold down the right button for a few seconds to see the peak boost and hold it for 10seconds to clear peak boost - This is useful for setting your boost levels as you'll see it go to 21 psi but if you check the peak it might be at 23 or 24 psi. be careful!

There is also a wastegate spring pressure or crack pressure setting. The proper way to set this is to get your boost where you want it and increase your crack pressure until your boost starts increasing and then back it off to before it started climbing. I didnt have much luck getting the spike / taper completely eliminated with the stock turbo. This value is the psi that your wastegate spring starts to open, not when it fully opens. lower numbers less spike, higher numbers more spike. I can't remember the value I had here, probably somewhere between 7.0 and 11.0. It ships super low, like 1 or 2.


To use the scramble boost you need to install a momentary switch to activate, I never used this option.

I ended up putting an inline resistor and running the solenoid off of the ECU using mrfred's direct boost control. I still use the gauge and the peak hold is a nice feature as ti tells you after the fact what the highest boost that the map sensor saw. I also utilize a JDM map sensor for the direct boost control.

 

thank you for your help, is it harmful to set the crack pressure more than 11? and what is a safe level to set my boost at after my tune or when it is getting tuned with my mods and 91 octane is the most i can get.

 

It seems to me that the higher you set the spring pressure, the quicker the turbo spools, but it also tapers off more and the lower the spring pressure, the slower the spool, but less taper, which makes sense. I believe the instructions say set the spring pressure to about half of actual wg spring pressure, or the pressure that the wg starts to open (crack pressure). I have nothing to back this up other than that's what I SEEM to feel when playing with the settings. I wish that thing had a loggable output like the rest of there gauges.

 

It wont hurt for you to try different things as long as your not overboosting the car. Like I mentioned earlier your car is not tuned to run the increased boost so I dont recommend going over stock boost.. about 21psi on the spike is near stock. As far as setting crack pressure, I gave instructions on how to set it, the instructions are from a tech on the AEM forums.

First set boost profile A to make 21 psi of boost on a 3rd gear pull. Make sure your running on boost profile A, choices are A, B, OFF depress left button to toggle through your choices. Now increase your spring or crack pressure until your boost goes to 21.5 psi. This is tedius as you have to exit the menu system to see boost again after changing crack pressure, they should have made it like duty where you can see current boost and duty settings for A and B. Now back it down to below where it began increasing. This is a good starting point, then if you feel it's spiking too much lower it, or if it feels like boost is delayed increase it. And yes biggie5252 if it spikes high at the onset of boost it will taper more at the end of the run. They are related to each other.

I suggest not worrying about trying to get a completly flat boost curve. The system is going to spike a little and thats ok, you dont want super excessive spikes or taper. Use your peak (hold right button for 2 seconds) to find out how much you are spiking. When I had my car tuned with that system I ran 23.5 psi peak boost tapering to about 19.5-20psi at 7600rpm.

 

soild info on this as I'm having issues trying to dial in @ 25 psi. i was tuned previously for 23 lbs and was set around 67% duty cycle. Now when I raised it to 73% I spike at 27-28 lbs tapering down to 25. I don't like that spike at all and was told that I should lower my WG crack pressure a bit, is that true?

 

^^^
where do you have your wg crack pressure set at now?

 

could the scramble boost be set to stay activated until u deactvate it, i know u can set a amount of time to stay active,?
could u use it for example to set a failsafe for meth injection kit, if failsafe triggers, it activates the scramble boost, set at a lesser boost duty or psi?

 

Where did you guys connect the manifold pressure line that comes off the back of the gauge? Any pictures? Thanks

 

it was set @ 12. I set it to 14 now and 70% duty. Spikes to about 26 and holds 25 till about 6k rpm

 

I connected it to the line that went to the stock boost gauge. If you don't have it you should be able to T off the line that goes from the IM to the fuel pressure regulator (where the stock boost gauge tees in) or you can tee into the line from the IM to the blow off valve.

 

This is where the after market boost gauge went that I'm replacing. Will this work?

 

yeah, it should. That's how the stock boost gauge is setup, and that's where my tru-boost is connected.

 

Are you using stock turbo/wga? If so where is your boost reference (gauge) and solenoid tapped from? I wish I could hold boost like that, although not so much of it. Thanks.