Greddy B-Spec II Tuning Guide

[sdfontanini]

Here's a breakdown of the desired Boost Pressure and the corresponding Greddy B-Spec II settings. Have fun, and good luck tuning.



SET:
- Sets the Boost Pressure.
- Adjusted in Percentage Value 0 - 100%
- 100% Highest Capable Boost of Turbo.

GAIN:
- Adjusts Boost Consistency

SET GAIN:
- Lowest Boost Greddy Unit will begin increasing Boost under WOT.
- Set as close to your desired boost as possible.
- If set too close to the SET Boost Pressure, will cause Boost Spike.
- Set to minus 4 PSI from your desired Boost Pressure. Example 17 psi for 21 psi.

WARNING:
- Used to Limit Boost Pressure
- When Exceeded the LIMITER will kick in and decrease Boost.
- Should be set 1 pis above desired Boost Set

LIMITER:
- Boost Percentage Reading
- Greddy unit will lower to this pressure once WARNING pressure has been reached.
- Set to between L.2 to L.4

PEAK:
- Shows Peak Boost Reading
- To Clear, go to Peak Boost Display and hold down SET KNOB unil unit beeps and ---- is displayed.


HERE ARE THE SETTINGS I USED FOR MY STOCK TURBO SETUP

LO (18 PSI)
SET: 50%
GAIN: 5%
SET GAIN: 0 kPa
WARNING: 1.44 kPA or 21 psi
LIMITER: 4%
RESULTS: 19 psi


HI (20 PSI)
SET: 50%
GAIN: 10%
SET GAIN: 0 kPa
WARNING: 1.44 kPA or 21 psi
LIMITER: 4%
RESULTS: 20.7 psi

NOTES:
Everything runs pretty smoothly. But I'm going to drop the SET GAIN down to 0.84 kPa so that it matches Denver's Atmospheric Pressure of 12.2 psi. Hopefully she'll run even smoother when I do this.

[MagnumPSI]

Turn the gain up. Also try and turn your set gain down a little.

Try and play with it so that you dont get boost fluctuations. If you do get over shot boost then turn the gain down a little.

Mitch

[MagnumPSI]

Originally Posted by sdfontanini

SET: 0-- This will have to played with. I find it hard to believe that this is at 0 and 20psi.
GAIN: 20%
START BOOST: 1.0
WARNING: 1.6
LIMITER: 5
PEAK: 0
LAST BOOST: 0

Try this.

Mitch

[sdfontanini]

Mitch, what should I set the SET to?

Would these settings be good for a stock turbo. I'm not looking to get the max power out of my stock turbo, I just want it tuned conservatively for DD use. 20 PSI is what I had my ECU flashed at, using 91 Octane. I think this is reasonably conservative.

Now I just want it to spool up sooner than later.

[sdfontanini]

See Spreadsheet Above ^ ^ ^

[BAMBAM]

Man I am glad I never got this thing. Looks like alot of work.... Good luck Steve.

[nicksalerno80]

You are not going to be able to get your turbo to spool that much faster like you are wanting with just the boost controller, it just doesn't work that way. How are you monitoring your boost in your car? Don't just go off of other peoples settings either, get an idea where you should be at and play with it. Just turning up the gain will give you a bigger boost spike, which is what you don't want. This is guessing gain and set mean the same thing as my Blitz.

[sdfontanini]

Well after a bunch of searching I found and made a spreadsheet listing the boost pressures and corresponding settings. See above in previous post if you're interested.

As far as monitoring my Boost Pressure, I've got an Autometer Boost Gauge mounted on my steering wheel, that lists pressure in PSI. I've got a Mitsubishi Boost Gauge located in my center pod that reads in kPa, and I've got my Boost Controller which displays pressure in both kPa and PSI. I know it's overkill, but I think I'm covered.

As far as boost spike, I haven't noticed this at all. Only issues I'm having is in 5th gear. My BOV tends to sputter at WOT. Don't know if I can fix this, considering Boost doesn't hold as well in both 4th and 5th gears with the Greddy B-Spec. Or atleast that's the word on the street...

Thanks guys for the help. This Controller really isn't hard to figure out, unfortunately this is my first time working with it, so it takes some reading to understand what's going on.

Thanks again.

- Steve

[BAMBAM]

The 5th gear thing will happen when you get rid of the stock BOV that is normal. Same thing I thought it never use to do it....lol it is because of the stonger spring in the BOV. at least I hope I am saying it right....lol any ways it is a normal thing with a fter market BOV and being in 5th gear. Just have to drive alittle different sorry mate.

[sdfontanini]

That's what I figured, can't do much but change your driving style.

WHAT's THE STOCK PSI on my Stock Evo 8 turbo? Anybody Know exactly? I'm assuming it's 19 PSI, but I don't know for sure.

Thanks,

[nicksalerno80]

Yeah, stock boost is around 19 psi then it tapers off to like 16 psi. But, with the stock plastic BOV, you can't really go much more than stock pressure, some don't even hold on stock boost........

[Evolvd]

I'm using the same EBC and although my settings will be completely different I can definitely recommend that you go by owners manual. It'll take quite a few 3rd gear pulls to get it down but each car reacts differently and will require different tweaks.

You might get your boost response to 2800 but probably no lower. The engine is just not moving enough air at that low of an RPM to spool the turbo. It's physics, not the boost controller.

[sdfontanini]

Okay guys, I was playing around with the Controller last night, and got to right about were I want to be running. All in all, this unit was very easy to work with. With no experience working with Boost Controllers, I can honestly say this was a piece of cake.

[Evolvd]

Good deal...enough tweaking and you should see very little to no spike or fluctuation other than the turbo running out of breath at high RPM.

[sdfontanini]

- Found the optimal setting at 50% / 10% / 0 kPa / 21 psi / 4%
- Not too Much, not too little. Car peaks at 20.7 psi.

I do notice the clutch takes a bit more of a beating, and everynow and again I get a smell of coolant at these settings, probably the compression reaching the upper limits of my head gasket I don't know. Maybe it's a hairline crack in the radiator, still trying to figure this one out. Anyhow, I'm enjoying it...probably turn it down to 19.9 psi for DD use.