GReddy Profec boost controller help

Hello guys, it's been awhile since i introduce myself. So i'm here again to seek some help in general regarding boost controller.

I just purchase and installed brand new latest GReddy profec boost controller ( installed and setting/tune done by professional tuner all the way from japan ) today.

I haven't had any experience with a boost controller before but i know that if you set it to the desire boost level it should stay/hold right?

Well after all tuning was done, i decided to test the boost controller. Lo boost setting is 1.0 bar or 14.5 psi hi boost setting is set to 1.3 bar or 18.8 psi. Looking at the boost controller graph setting my boost look kinda funny. Please look at the picture:



The first picture shows the lo boost setting and the graph have a spike and the drop down and slowly building up boost. I manage to get 1.13 bar or 16.4 psi. This is tested on road starting from 4 gear 2.5k rpm all the way to 7k rpm. ( my rpm limit is 7.5k)



Second picture is hi boost setting i manage to get 1.4 bar or 20.3 psi same gear as the above 4 gear from 2.5k wot till 7k. The graph also shows a spike then drop then slowly building boost.

Shouldn't the graph suppose to be rising and then have a constant/flat curve once it reach the desire/set boost?

What makes me tick off is that this was done by professional, heck done by some imported renowned tuner from japan and yet they fail to let me know during the dyno run.

Hope you guys can help me with this problem. Somebody gonna get a hurt real bad ( russel peter's dad voice ) tomorrow morning.

Here's a picture of my dyno result after they "tune/setting" my boost controller.



The before result was 240 ish whp then after they tune/set i manage to get 295 ish awhp. Every this is stock except for dp and tbe.

Cheers and have a nice day.

Except for the spike I see nothing out of the ordinary on the surface. Remember that a stock turbo, no matter what kind of boost control you have, is going to tapper off in the high RPM because it simply does not have enough steam to keep the boost level. If you want consistent boost through red line then a bigger turbo is in order. 295whp is pretty damn good on that dyno for stage 2.

At what RPM does the turbo reach peak boost? At the very least I would have your tuner look into that spike.

If I was tuning your car all I would have suggested was either a 3 port EBCS or nothing, and then tuned the crap out of the factory boost control. It beats any after market solution on the planet if you know what you are doing with it.

Is it possible for my actuator not holding boost even lo boost? Is there any way to know if my actuator is faulty/ not holding boost.

I went there again the next morning and complain to them regarding this graph and they reset it and i get this result:



That is the low boost. Still creeping i guess.



The second picture is hi boost setting. No spike but i'm sure the boost is too high should be 1.3 bar max but i get 1.5 bar

Then i try to lower the boost start setting of the hi boost to 1.3 bar and the set to 55. This is the result:



There is spike so i lower the start boost to 1 bar this is the result:

.

A small spike in the graph. I haven't touch and of the other setting such as limiter and gain. Will try and go test it on the road later tonight.

Damn blasting on the road at 12 noon is such a bad idea hahaha way too hot.

Anyhow does the graph have any improvement from yesterday?

Shouldn't the graph look more like this:



The image is taken from the manual book. From what my friend said the graph suppose to reach peak boost first then the controller will limit the graph to constant flat lastly taper off?

I'm not sure which rpm i have the maximum boost since i'm only focusing at the rev. All i can say is that when the graph spike the range is around 3.5k and i felt like the car drop power then gaining back startinh from 4k till 7k.

The picture below is taken yesterday after they reset it and dyno it again. I ask them to tune low boost to 1bar and hi boost 1.3 bar.



The creep is obvious since the graph is climbing and the controller doesn't limit it. This is 1st run for low boost



This is hi boost setting. 2nd run.



That's them "tuning" my car.

Cheers and thanks in advance for the help.

Looks like they are ironing out the spike issue. Using the profec is not common in the subaru community so it will be hard to get alot of input on it. IMO its alot of money to spend unnecessarily. like holy said there already is an EBC on the STI that can be used quite well and easily. I would go that route. the only additional thing i would rec. is an MBC. They are a little cheaper and deliver rock solid and consistent boost especially with elevation and temp changes.

Shouldn't the graph look like this:



The graph that i'm getting is slowly increasing or creeping where there is no action of the controller to control the boost. This is during lo boost and hi boost setting.

My friend explain to me the graph should reach peak boost/ desire boost level first then hold the boost till it taper down at 6-7k rev.

This made me very worried that it will damage my engine. Some suggest me to get uprated actuator and port my waste gate or go external waste gate.

And other possibility such as boost leak, wrong installation of the boost controller or is the setting of the controller is the problem?

FYI i'm using cusco downpipe (catless) and HKS Hi power Silent TBE currently and my turbo is vf35.

Other mods are:
Dw300 fuel pump
Zero/sport induction pipe
Blitz dual sound bov.

Any help guys?

Im definitely a noob to tuning. But whatever boost controller you're using should be able to get you good boost performance. There's no reason to get any more physical mods like EWG to get the performance you're looking for. As was said before, I havent seen this boost controller used much in the STI world, at least domestically. The shop really should be able to dial in whatever you want, but it might take them more time (costing you more money) since it's probably a new system to them.

But the LAST thing you should do is go buying more bits to fix the problem. If the shop cant get it working right, I would consider switching to a standard 3-port EBCS or an MBC and let the shop tune those. You can probably sell the GReddy for almost what you bought it for, and that's certainly cheaper than buying EWG setups or modding your turbo.

Thanks grinder for your reply. Last night i've tried a MBC. The result is the same. My boost keep rising past my set point 1 bar.

We have narrow the problem down to either my actuator and not the boost controller setting.

This is the graph that i suppose to get if the controller is working properly:



That graph is from a friend of mine it reach peak boost and then hold the boost and taper off at 5.5k to 7k rev.
He have installed uprated actuator (14.5 psi spring). Before installing the actuator his boost is also inconsistance.

The "shop" that i sent my car for tuning certainly doesn't know shit. Even the tuner said to me that it is his first time tuning the GReddy profec. This is the only pro shop that have a dyno for 4wd so i had no other option buy seek them for tuning.

Now that the tuner have return back to japan the shop have nobody to trobleshoot my car. The tuner will be back 3-4 month time.

Will update once i have installed uprated actuator.

Cheers and have a nice day.

Time to get a tactrix cable and have some etuning done.

Sorry to hear about your issues that you have had.

We are using the tactrix cable. The "tuner" recommend me to reflash/remap using ecutech but i decline the offer since my ecu will be lock and since there isn't any other tuner that are able to use it later if i need to remap it.

Will update once i have install the uprated actuator. Hopefully it will stop my overboosting/creeping and boost spike.

Cheers.

Hi [MENTION=3126]ezie[/MENTION], any updates on ur problem? Solved it already?

Hi [MENTION=4964]Remedy247[/MENTION] sorry for the late reply. I manage to solve the boost creep using a new actuator (15psi). Just using the default greddy profec setting i am able to get the desire boost set.

I have also done some fine tuning to the profec boost setting and able to hold 22psi with hi boost setting and 19 psi with lo boost setting.

Hope this helps and happy new year guys.