I was looking around online and found that there are still questions about dialing in the Greddy Profec B spec II even with the great write up we already have on this website. So I thought I would post up my findings in how I understand things in an effort to make things a bit simpler for those that still have questions or want a quick reference guide. Keep in mind I'm assuming you know the basic functions of the dials on the unit.

Here is a basic chart type setup to aid in figuring things out
(I personally chose to use PSI instead of KPa.)

CONTROL—MEASUREMENT—“EFFECT”—(DETAILS):

Set -- % -- “Desired boost psi”
(Use to set general boost level)

Gain -- % -- “Boost consistency”
(Use to minimize boost taper—proportionately affects the overall boost level)

Set Gain -- psi -- “Boost response”
(Controls when the wastegate starts to open–use to maximize turbo spool up)

Warning -- psi -- “Maximum boost level”
(Sets the maximum boost that you do not want to exceed)

Limiter -- % -- “Maximum boost modifier”
(Sets the amount to reduce the boost psi if warning level has been reached)

Peak Boost -- psi -- "Highest boost achieved"

TUNING PROCESS:

Initial setup: (I was looking for 22 psi)

Set 30% (this should put you at roughly 12-15 psi of boost)
Gain 5 % (this is the lowest setting available)
Set Gain 18 psi (desired amount minus around 4 psi)
Warning 23 psi (I was already running 23 psi w/ ECU control)
Limiter 1% (there’s really no reason to do more than this—the car can easily handle 23 psi with a stock turbo)

1. Turn off the unit to set it to PSI, then turn the unit back on and turn PEAK BOOST to "on".
2. Set the WARNING to one above desired boost, and the LIMITER to 1% (or whatever you want).
3. Start to increase the GAIN first to minimize or remove the taper. In most cases you will not be able to completely eliminate the taper. Increase gain in small increments until boost is held pretty much to redline. If boost spike/surge occurs – go back down in value until it subsides (at this point you’re done with the GAIN).
4. Adjust for the SET value next—simply by adjusting the percentage until you reach your desired boost levels. In my case that was 22 psi.
5. Set the SET GAIN value last—the reason for this is because you want to get it as close to the SET value as possible to maximize spool up. Once you hit a boost spike or surge—lower it down till it subsides.

All done!

 

what did youre final tune end up at?

 

+1

 

I'm still fine tuning. It's hard to find a good road around here that has no cars, cops, etc. I did run into a snag with some boost spiking that I couldn't figure out, but after inspecting the valve install--it still had the plastic cap in the NC outlet. Funny because it didn't show up till later.

I'll post up again when I get the final setup.

 

Currently--it's set about here:

Set-60%
Gain-6%
Start Boost-14.5 psi
Warning-24 psi
Limiter-4%

I'm boosting at about 20-21 psi, and losing about 2 psi up top. Spool up occurs around 3k rpm under normal acceleration, and almost immediately upon aggressive acceleration.

My next step is probably to lower the SET a bit, because I'm going to increase the GAIN to try and see if I can minimize that taper just a tad bit more. Then I'll readjust the SET again to get it right at 22-23 psi. Once that's done I'll increase the START BOOST until I get some surging, and turn her back a notch or two.

 

The surging really helps in telling you if you have your settings off or not.

My car which was already modded and tuned for 22psi was set to 54% SET value.

I found that in colder weather it would overboost to ~23-24psi so I turned it down to 51% SET value which kept me between 20-21psi.

I noticed that when doing that, I get less surge on the top end. So, I'll probably play with my GAIN value and my SET_GAIN to get rid of that.

I love the Spec II: A lot of features that the Profec B doesn't have. I'd recommend this EBC to everyone.

Tony

 

Wow! I guess are cars are very different...

Here are my current settings which have triggered no creeping or surging to date:

Set 70% - (20.8 peak boost)

Gain 8% - (no noticeable taper up to 6500 rpm)

Set gain - 18 psi (spool up is quick!)

Warning - 23.1 psi (have never hit it)

Limiter - 3%

I may try and go up a bit in the set value before I start increasing the set gain. I wanted to pretty much be at 22-23 psi in the higher gears. I didn't see anyone else with such a high SET value yet---but then again--it makes sense because when the ecu controlled it Chris at AMS said he upped the boost to the stock turbo's safe limit--which was right at 23 psi. So since 100% on the boost controller is the physical limits of the turbo and wastegate, it's logical I guess. I still haven't hit any surging...I figured I would by now but not yet.

 

Just curious--how would you overboost on the top end if you have the warning and modifier set? I never understood that part of it. I know the pamplet states that the unit will not protect against overboost---if that's the case than what the hell is the limiter for? Ya know what I mean?

But so far I haven't hit it. Perhaps I'll understand better when it happens.

 

The warning and modifier is a great function and it works. If you turn your EBC to 30psi for example but forgot to change your warning and modifier, say it was still set at 23psi, then it would indeed kick in at 23psi.

My personal situation is that it would spike/surge when first getting into boost and on the top end. It levels out at 19-20psi, it's just that split second where it jumps to 24psi, which I don't like.

Boost spikes of 1 or 2 psi isn't a big deal to some...but for me, why get greedy and boost to the limits of your fuel (pump gas) and have these tiny headaches and potential contributions to engine damage?

I rather turn it down, from 54% to 51% and hold my 19-20psi with my 20.5/21psi spikes.

 

Hey yall--got a gooood setup now. I'm boosting consistently 22.7 at WOT through almost all gears with no taper and no spikies.

Set is at 73%
Gain is at 8%
Start boost is at 18.5

I'll be moving up a bit here and there on the start boost to see how high I can take it--even though the spool up is already pretty dang quick.

 

Ok i have a huge problem I guess.

This is what I have going on with my Evo IX GSR with a Profec Spec 2

Set 89%
Gain 8%
Start Boost 20.6 +-


Ok the thing is, I'll lower my set down to around the 70s area and all I will hit no matter what is like 13. Once I start getting in the high 80s area that is when my boost starts hitting 20 or so and holds decently. My problem is I can't get any higher. I want to be around 22-23psi but no matter what I do I can't achieve that. If i change the set to 90% it's crazy and any lower than 87% it sucks. I pump up start boost and nothing really happens. I stay around 20.6. I go higher around 25 and then it starts to jump around.

 

You need to check the install. Make sure the plastic cap is out of the NC terminal. Then lower your set back down to something more like 60 and start testing to see where your boost is at again. Mine's at 22.7psi at 73%

Your gain is probably about right--you don't even need to raise it up any more once you hold boost at WOT thru to your desired shift point (normally around 6.5k). I've heard of some people getting to 9 and 10 percent--depends on your car's setup.

I'd imagine that your desired boost is 22-23? Because your start boost is really high. If you can do that without surging that's great! The closer to your desired boost level the better for your spool up. I've got my set at 19.5 I think right now.

Good luck. I can almost guarantee your cap is still in.

 

Yup thanks a lot. Problem was the stupid cap on the NC terminal. When doing the install i swear it said to leave the cap in but that was Greddy instructions. Spool is wayyyyyyyyyyyyy better now, i used to think the EBC sucked but now its great. I spool directly to 22-23 and hold it well. Needle is solid and everything.

 

No worries. Glad to hear everything worked out well.

 

I just realized something--if you're spiking--then you need to turn down the gain or start boost a bit...try the start boost first, if that doesn't help--then try the gain until it goes away. Then go back and readjust your set and/or startboost. You shouldn't be spiking at all. Mine spools up to 22.5-7 right away and holds. My warning is set for 23.1 and has yet to hit it in any gear.