Profec-B II Boost // problems

[TurK]

i have a profec b II boost controler and im boosting 14 psi.....i have set at 40% gain at 10 and set gain at 90........well anyway i have my warning set at 14.5...and got the reducer at 5%.......what i dont understand is whenever i get on the gas and start boosting around 11lbs the warning comes on, when i have the warning set at 14.5? can anybody explain this.? i thought my set gain was too high but i lowered it way down and still the same result....

[slider2828]

Why do you have set gain so high. Set gain is like set boost on the profec E01. I assume you have 40% for manual boost, 10 gain and set gain at 90%. 40% should land you about 14 PSI, I am guessing, 10% gain is a little low. Your set gain is SKY HIGH!! Way up there..... Read the manual next time but I know it is confusing. Here is a interpretation of the manual.

Actuator percentage = How much boost you will get
Gain is how fast it will spool up.
Set Boost = is when it will hold the pressure till the actuator will open.

Based on me reading the manual, there is no set gain just set boost, but maybe in your profec spec there is set gain. Please confirm

Try these settings, keep the set boost at 40% solenoid, then set gain around 26 and your start boost at 12. See if this works for you.

Your set boost is to reach the target boost mark (14PSI in your case), gain is say how fast your solenoid opens up. Open too fast and it will overboost (or called boost spike). Your start boost should be no higher than 2 psi less than your set boost. So if your set boost is 14PSI, your start boost must be around 12PSI or less. Please make sure your start boost is reading pressure, check your manual. Based of Greddy's website for profec b II spec 2, my settings should work for your car. I believe there is no gain and set gain settings as you described in your paragraph. Better list the settings as they appear in the boost controller and I can better help you because it seems like you are a little confused about the settings. O btw, please make sure this is for an sr20det t28 or t25, as the settings I am talking about are for those two turbos. I assume they are t28 or t25 because based what I can tell, your boost numbers match that of a t25. Good Luck... I will check back later....

[TurK]

hey thanks for your time, i tried this on the way back from work....i left the set at 40% i raised the gain to 20%....and lowerd the set boost to 50.....and man it made some difference....the boost woud hold really good at 13psi and you coud tell by the pull of the car that it helpd....and for some reason my turbo timer(greddy) woud always set to like 7 minutes after i get back from work....and i realized today after playing with the boost controller that the turbo timer woud be between 30-37 seconds and it woud drop instantly when i woudnt get on...whic this is great.....tnx for your help....i hope the car stays this way... because i just got tired of having boost spike one day and not the other...

[TurK]

Originally Posted by slider2828

Actuator percentage = How much boost you will get
Gain is how fast it will spool up.
Set Boost = is when it will hold the pressure till the actuator will open.

Based on me reading the manual, there is no set gain just set boost, but maybe in your profec spec there is set gain. Please confirm

Ok sorry for the confusion it is called Start boost as i checked the profec B specII booklet.... and yes its a t28 stock s14sr turbo

on the booklet it confirms that.

SET: This mode is used to set the desired boost pressure.
This feature controles the duty rate of the Valve Unit which controls the boost.

GAIN: This mode is used to adjust the boost consistency.
Even if the SET boost is not changed, by incresasing the GAIN value, it will increase the boost.

START BOOST: This mode is used to adjust the boost response.
This feature basically adjusts when to start opening the wastegate.
.If the START Boost value is closer to the SET boost value, the spool up will be faster.

[slider2828]

Glad to help... I know its a little confusing, but you know hopefully these settings would help people in the future because greddy uses all the same settings with all their profec's in manual mode because the Profec E-01 has automatic mode (Which is junk on high boost application).

Ok... One thing though bro, 50 is WAY TOO high still for the Start Boost. Remember what I said, Start boost MUST be 2 PSI or more lower than your boost pressure. So you are boosting perfect at 13 psi, your start boost should be at 11 bro....

Next lesson advanced turbo tuning. On your profec I know you don't have a boost log, most people don't BUT, you are probably not making efficient boost right now. So here is the next setting, you want about 14 psi on boost so you wanna turn up the SET to about 42 % and keep your Gain to about 22 - 26 less than 30 for sure. Your start boost should then be raised to about 12-13psi..

So your numbers should read
Set - 44
Gain - 24
Start - 12

Basically boost spike is controlled by Gain, start boost controls pressure drop. So keep an eye on the boost levels, so 44 should bring you peak boost about 14 psi's - if not 14, raise it a little or if too much boost then lower it to 42(2 notches at a time to be safe). Then the gain try 24 then 26 (again 2 notches at a time) If you have boost spike and you know your limiter kicks in, then you turn down your SET boost less than watch you tried. Finally Start boost, keep at 2 PSI lower than your peak boost. So once again if you hit 14psi, then start boost should be at 12. Got It? This should give awesome torque and kick and you WILL notice right off the bat......

Remember SET controls peak PSI, Gain Controls Boost Spike and Response (ie. Response would be can't reach desired peak boost) and Start Boost is always 2 PSI lower than your peak boost(This settings is recommended by Greddy, also in the manual).

[TurK]

see what threw me off is that on the booklet it says the setboost is what controles your wastegate opening...for quicker spool...... the gain it says for consistency....

so i figured turning the set boost will give me quicker spool not gain....but i dont know with this new setup seems to be working betteR? and how do i know howmuch psi im at on setboost cuz it only gives number nothing beside of it like a % sign or anything i woudnt know howmuch psi im off the set

[TurK]

wow i just got back....and damn.....im scared to get on it now....cant stop from going sideways on straight road....anyway i was out trying to tune it at 40 20 12 and it just woudnt stop spiking....well i turned up the set to 42...and gain at 22 left set boost at 12...BAM magic... awesome man no spike...pulling very hard....the asphalt cried.

[slider2828]

Awesome, I am happy you are getting it... Yah you can offset the boost spike by raising the SET value. So it holds at the correct PSI without spiking. Yah those T25 or T28 mofo's with correct turbo boost settings actually can really freaking pull. I have a T25 stock from my JDM clip and I keep up with an STI on a 2nd gear pull.... Damn 4 wheelers pull like mofo in first.... *shakes fist at 4 wheelers*.... grrrr.....

As per how much you boost, you should have a boost gauge in your car, cause greddy profec B II dun really have a real time boost gauge in it. (Kinda sucks that is why I have a profec E-01). But anyways, with what you have you only have Peak and Last boost. Peak is the most boost you have had in your car EVER and there is memory on this one (you can only manually reset it). Last boost is the last boost recording and resets every time you boost. (Could be useful). But hahaha you know what if you ever watched the drift bible or like any S13 car, hahah they have a standard analog boost guage.

O and those stupid manuals are written by tech writers, not by people who tune.... So sometimes you just have to make sense of it. But based on your experiment you can see that the gain really gets the boost up there and maybe spike it, while the start boost just gives it good consistency. I think the profec-e01 manual explains it a little better, but not much.

O BTW bro... hopefully you are doing your other homework, like having a front mount or at least an aluminum hotpipe, any type of FPR and bigger injectors and some ecu tuning bro..... Cause you at 14 PSI, you are definitely maxing out injectors and you are definitely saturating the crappy side mount intercooler, so you are boosting hot air into the engine. Note 14 - 15 psi is pretty max on a T28.

Happy Boosting.... I only write this because a lot of people bang on the Profec's saying they suck compared to the cooler Blitz controllers. But I am just trying to get rid of that idea.... If you understand it, you will just make your turbo scream for more.

[Ess14]

Slider I don't know if I read you right but the Profec B II does have a real-time boost reading.
It also blinks for a second your last boost and keeps your max boost as you stated.
By the way thats a great write up...

[slider2828]

Well I was just reading the settings in the manual, cause it just says peak and last boost..... Does it really go like from -10psi and all the way up to 14 psi? Thanks for the comments.... I have no idea, I own a profec e01

[Ess14]

yeah it reads from negative something all the way to far past 14 psi if you let it. I use kpa not PSI, not exactly sure how far negative it goes. It reads X.XX

[DoriftoSlut]

Originally Posted by slider2828

Happy Boosting.... I only write this because a lot of people bang on the Profec's saying they suck compared to the cooler Blitz controllers. But I am just trying to get rid of that idea.... If you understand it, you will just make your turbo scream for more.

Awesome write up and knowledge. I, for one, hate Profec B Spec II and e-01 for this reason. Its super confusing. I have Profec B spec I. I also have Defi link boost gauge. I have my gain set at about 40-50% (its just a turn dial w/ markings on the old spec I) and low boost dial at about 33%. External Turbonetics Evolution gate w/ .7bar spring. Turbo is a t3/t04e. It spools like a psycho and it never peaks. I have the boost at 1.1bar, every single time... consistently holds 1.1 bar with no spikes ever. That's why i like the Spec I more than spec II. We should have this thread archived for the next time someone with the demon boost controllers is having problems...

[slider2828]

See I dunno much about the profec 1 at all because it ain't even on the market any more. Although with the newer boost controllers it might be even better lol if you know how to set it up. But the profec e01 is a different animal with settings up the arse that really if dialed in is awesome. Like it has something called scramble boost (blitz) or take over boost. Basically on the fly you can change from a 12psi boost curve (boost curve includes all gain and start boost settings) to a 14 psi boost curve at a touch of a button. Another little item I LOVE is called the RPM offset. You know when people say o I boost to twelve but it slowly loses boost as the RPM gets higher. People say that is normal which it is because it runs close to the limite of the turbo, well the rpm offset keeps on opening up the solenoid (or keeps increasing the SET value a little bit by percentage based on what RPM you have). So I boost at 13.5 daily on a T25, but most people can get to 13.5 around 4-5 grand rpm, but starts losing boost. But with my RPM offset settings, it stays up at 13.5 or around 12.5 -13.5 at even 6500 RPM.

Its these little things hahahaha.... but it helps the need for Juice... Good luck guys...

[DoriftoSlut]

That's cool. I guess in my case (size of the turbo) sicne I don't encounter those issues ignorance is bliss. My roomate has an e01 and i just hate setting his car up, it always loses its stored settings somehow. I think maybe cause he's on a big turbo but like... 7-10 psi all those cool functions of the e01 get kinda fussy. I'll show him this thread and maybe we'll get his car dialed in a bit better...

[slider2828]

Yah the E01... forgot the automatic tune... Risk of tickets and revs the car like forever and takes too much time. Just do the manual mode... I run 10PSI for the low boost on a T25 so my settings are
Set 35
Gain 23
Start Boost at 8.3

Try it, lemme know....

[sr20tom]

Going with turks question. The start boost is not in psi. In order to get my boost to 18psi i need 55% set. I tried turning the gain up and down and it either spikes and falls of hard or it falls off slow to 12psi. And the Start boost is not in PSI. So should i set it to 16 or 53??? So Anoying going down the track thinking you are at 18 psi but its really 12.5 . I need Help

[slider2828]

Damn I was afraid this will come up soon. But you never really read the write up it looks like. Hmmm SET is a % of the Solenoid, Gain is a % and start boost should be in PSI. what is yours in kpa or psi? Read your boost controller to see what are the units, because it says it....

18 PSI is probably a SET value of around 55% which is correct, your gain should be around 28-35 (Test this slowly because this is a major component. If too high you WILL boost spike). Same with the start boost which if you are boosting 18 psi it should be at 16psi. If your boost controller is NOT in psi units, read f....ing page 14 in your manual to change it. Trust me it works, just read your manual more...... Good Luck

These settings are assuming you have a T28 Turbo. To me it seems like you are turning knobs and not understanding what you are doing... good way to blow your turbo bro..... Do everything slowly.... and don't jump the gun

[sr20tom]

ok i did what you told me but for 15 psi cause i dont have 100 octane. I put 45%, 26, 14 and the boost still fell off to 10psi now. So i lowered the gain to 20 and the boost fell to 13. I was going to school so there was not a lot of room to boost. So should i raise or lower the gain.

Thanx

[slider2828]

Try 46 25 12. Make sure the 12 is in PSI and not KPA.... You have a T28 turbo right?

[sr20tom]

im maxing out my T25

[slider2828]

Try 46 25 11.... that is for 13.5 psi....

[slider2828]

well dude.... 14psi maxing out the turbo that is if you don't blow your motor without the right upgrades.

[sr20tom]

i got the right upgrades i need 18psi on 100 octane

Maby its the gear that i am in. I kept doing second gear pulls and it kept falling off, Now its at 44, 32, 13 and in second it still falls off, but i did a third gear pull and it dropped from 15.5 to 14.6 and i can live with that. Is second not spooling it or something?

[Tex Willer]

The T25 with std actuator will not manage a flat boost curve at this level.
The exhaust backpressure is rising at higher revs, causing the boost pressure to drop.

[slider2828]

Yah you gonna get a little drop off... That is just how it is.... Nature of the turbo.... If you had a Profec E-01 you would have something called RPM offset which tunes your turbo a little more... Please read my above post.

[TurK]

wow thats weird because im hitting 14psi on 42% 24 12.....and knock on wood... its pulling hard and i dont think its falling off at anywhere nor spiking.

[slider2828]

You have a t28, much different from the guys t25 cause your housing is different. remembe 42% of the solenoid/actuator... everyone's setup is different, so it is hard to say what everyone really gets you know. It is up to the condition of the turbo and other stuff... Thats just life....

[TurK]

true...i forgot about that.....neet more Set to have the same lbs of boost...

[cc4usmc]

ok...well i have a stock s13 blacktop w/ 3inch downpipe and exhuast. i just installed my Profec-B II. i want to boost around 10psi. what sould i set my controller at?

[slider2828]

I would probably just suggest reading the above post and not get settings as everyone's settings are different with a different setup. The above post should give you ideas on how to tune your turbo.

Just run
34 - Set
23 - Gain
8.3 - Start Boost....

But in order to get perfect efficiency, read the above posts and tweak it a little.