setting up an electronic boost controller..(aem tru boost)

[BOOSTEDSUPRA]

sup all, and merry xmas, ever since i put this pos in my car ive been having difficulties setting it up. im talkin bout my aem truboost controller. i used to have a manual one and i made a good amount of power on my stock ct-26. now i have a 60-1 comp ball bearing in it, and i hooked up this thing, and cant get more than 10psi outta it.

i was told to put some air to the controller to see if the actuator is functioning, it is, i have bounced around the contollers duty cycle and cant seem to find a sweet spot. and i even did the lame ass "newb" thing and had no vacuume going to the wastegate at all and carefully spooled it up and back down, and it boosted just fine.

i guess im asking... HELP!! lmao. does anyone have a sugestion as to what i should set the duty cycle at? or close to it. im not mechanicly lame, im no spelling bee champ, but i can machine and build parts, lol. heres what i "think i know" about boost controllers....

running on a "duty cycle" method, setting it at a 50% dc will result in the actuator being open half the time and closed the other half...??? setting it to it max.. 90%..will result in it being closed 90% of the time (which im guessing means less pressure to the wg) and open 10%...???? so wouldnt that mean if i set it at a 90% duty cycle i should boost till armageddon?!?!?

and yes i watched the lame video at the aem website, many...MANY times, lol. can someone PLEASE help with this, :biglaugh:

 

[black89t]

what is it set at right now?

 

[SideWinderGX]

I only touched two things: WG spring pressure (titled SPR I believe in the list of variables you can change) and the duty cycle for A/B.

Spring pressure is tricky: the higher you set it, the quicker it spools (wastegate won't crack until this pressure) but the better the chance of spiking (or for me running into fuel cut). Too low and it spools slower.

As for duty cycle, let's assume you're at x% duty cycle and are getting 10 psi. Increase the duty cycle by 5% and see where you're at then...keep increasing it by small increments like that until you see a good psi.

Note that variations in ambient temperature will alter the psi you're seeing even though the duty cycle stays the same...higher psi on colder days, vice versa.

 

[BOOSTEDSUPRA]

right now i think it is set at 45 or 50%, and i started at 25% going up 5% each time. and i noticed that on my spr setting, higher number, quicker spool, noticable quicker, i think i finally got frustrated at like 10 pounds on spr and said f it. with a manual i hit 17.5 psi and it made great power on old turbo, and was just barely above the lean (holy shit... oops) on my af guage. i will try putting the spring pressure at where i want my psi to be.... although when i had it at 15....it didnt make 15 pounds of boost at a 90% duty cycle...grrr, idk,

 

[black89t]

try like 4-5 on spr. and 50-60 duty cycle.


its hard to say though what will work for you setup. each car is different. i remember slowsc or something along those lines has the truboost on a single 1.5jz. i asked him and he said he got the best spool/steady boost with spr at 2-3 running like 20ish psi. i think he was running a tighter wg spring on his ext gate then fine tunning with the truboost.


all in all mine works great, but it did take a while to get the truboost to spool and hold boost right. then again i think all ebc's are like that.

 

[SideWinderGX]

My 'A' setting is between 60-65 and it boosts around 12 psi. Keep going up and you'll eventually hit it haha, you were almost there.

The 'A' and 'B' settings are in duty cycle...the SPR is in PSI. Crank the duty cycle up a bit and fine tune the duty cycle/SPR until you find a response time/boost pressure you like.

 

[sethron71]

Not gonna lie I have tried a whole lot of things with the Tru-boost and it is pretty damn primitive and simplistic. It really doesn't have the precision it needs. If you set the SPR to like 5 as they recommend spool is super slow and I still say some creep and spike so if I set it to 2 it is steady but so slow to spool! So I tried all the way up to 15, what a difference it the car. When I just turn the controller off to WG pressure it feels fast at 10psi then it does at 15lbs on the controller because of the spool issue.

But my SPR is now at 5psi
Duty Cycles are 42(16psi) and 50(18psi)

But I will be switching to the AEM EMS boost control soon and I will have a direct comparison as there are tons of options to help with all the issues of the tru-boost. But if you search the web it is a very common problem.

Seth

 

[BOOSTEDSUPRA]

wow, u guys are getting results like i want, lol. i spent the weekend rewiring everything and routing it how i like, (ocd kicked in) lol, now i have my matching aem af guage, and i gotta learn what thats telling me now, weird, i am set at right now spr 15 and dc at 64%ish i think. all i get is a spike to 11psi.

i set the boost guage at spr setting 15, and got 11psi for a second and it dropped off to about 9.9... that is at 63% duty cycle, im gonna start all over, spr at 5ish, dc at like 20, and go up 2% each time. till ither i get it right...or get pissed and rip it out!!! :biglaugh:

if i can figure out how to get vid on here, i will post some stuff while its not raining.

 

[MKIIISupraGuy]

I run the Truboost too, and yes it is a bitch to get it tweaked in, so I definitely share your irritation. Anyway, I am on a stock CT-26, my setting are:

Spr : 7.8
A: 55
B: 45

- I boost at 11.5 under full throttle everytime, and about 8.5 to almost 10 at 3/4 throttle which is where I usually am at. Your running a 60-1, so I would say try Spr at 10, A: at 65, and B: at 55. If you end up a few psi shy of your max psi goal, turn up "B' only until you get what you want. Those settings should net you about 15 psi., so if you need to bump it up, it won't take much. Are you still on stock WG ? If so you might want to try the Spr at 8.5, if it spikes too quick.

 

[SideWinderGX]

The SPR setting is in PSI. If you want to boost to 15 psi (for example) and the SPR is higher than that...the wastegate won't open and it'll spike all right haha.

Seth, supraguy, good info!

 

[BOOSTEDSUPRA]

..ok, now im a little confused, lol.

setting "a" and setting "b"... isnt that just so you can have 2 different settings? i.e. track setting and a cruise setting? or do they work together somehow? and idk what wastegate i have, it is the one that came with the comp turbo. it'll do about 8psi hooked up stock. im about to rip the damn thing out and stab it through its heart!!!! i will check this again for any feedback tonight and go play with it a lil after work.

 

[Zumtizzle]

Note to self.

Don't buy AEM Tru-boost...lol

 

[sethron71]

The SPR setting is in PSI. If you want to boost to 15 psi (for example) and the SPR is higher than that...the wastegate won't open and it'll spike all right haha.

Seth, supraguy, good info!

This is not true, if you read the manual and look on the forums the SPR is totally setup depend and has nothing to do with your boost target. It is simply trying to give the controller a reference for how strong your stock WG spring is. This is why they tell you to try a wide range that works best for you.

Really the only to set it up properly is to start low, say 5 and if you don't see a boost spike or creep then step it up to 6, then 7, then 8 and so forth till you see a spike or creep and then set it down by .1 till you don't see it anymore and leave it. And vice versa, if you see a spike or creep at 5 go down to 4, 3, 2 till you don't see it any more and then dial it back up a touch till you just see it again and go down .1. I personally think the gauges filter number is too low and it reads to fast because when I boost hard the gauge will show a max psi that I never saw because it happened so fast so you have to be careful with that. Also it is such as fast spike that my AEM doesn't even see it in the log, but it has a higher filter factor to smooth out the map signal.

HTH,
Seth

 

[SideWinderGX]

What I said is absolutely true.

-The SPR is certainly measured in PSI
-If you set the SPR higher than the boost pressure you would like to achieve (for example, 16 psi spr and 15 psi boost) it will absolutely spike

SPR == pressure at which the wastegate cracks open. If all of the exhaust gasses continue to flow through the turbo all the way up to your maximum psi you'd like to see, and THEN the spring cracks...well, it'll spike above your intended target all right.

You are absolutely correct in saying that the intended target boost has no effect on where you start the spr pressure... but you'll also notice I said nothing relating to this anyways

 

[BOOSTEDSUPRA]

i understand what you both meant, and both of you are right. i understand how the spr settings work, and yes, if i do set it to a higher psi, it will spick to almost the setting of the spr, but drops off when the controller kicks in due to the lack of me setting it properly, lol. i tried a couple different settings, got nothing, i am going to try the "spr at 5, dc at 42 netting 15psi, and dc at 50 netting 18psi" and see if that helps.

if i cant figure it out by this weekend, there will be a boost controller for sale!

 

[SideWinderGX]

And to answer your question, yes, 'a' and 'b' are two different settings...like you said, one can be used for daily driving and the other for the track.

Don't get frustrated if the duty cycle you think will make x psi doesn't...keep trying! Just a bit more time is all you need haha.

 

[BOOSTEDSUPRA]

just a quick update, i have not been able to play with it due to my clutch master cyl crapping out on me. dealer should be delivering it to my shop today, will be in by tomorrow.

 

[BOOSTEDSUPRA]

ok, ive been through almost the whole damn dc settings on this pile of dung, is there any way of really testing this thing? ive put pressure to the controller and heard the solenoid working, but what if i mess with the dc settings, should the solenoid change pich? cause its esentually operating slower or faster? I.E letting more or less air through?

 

[SideWinderGX]

...you test it by driving your car and seeing where the pressure is at No idea about the pitch thing.