Greddy Profec B Spec II on a T25

[SpawnedX]

I want to run about 12.5 to 14 lbs of boost on my T25 and have a Greddy Profec B Spec II EBC. The problem is I either spike and get fuel cut or cannot hold boost. I think I am just not understanding how the settings work.

Here is what I have so far:

SET BOOST: 32%
GAIN: 1%
SET GAIN: 11

It is sporatic, sometimes I can boost 1-4 at WOT and hold consistent boost at around 12.5 other times it just starts losing boost as the RPMs go up at an alarming rate. In 5th gear it almost always spikes and causes fuel cut, this does not happen often in the other gears.

Mods on the car:

Injent Intake w/ K&N Filter
Aluminum Upper and Lower SMIC Piping
Coil-On-Plug (2.7L Coils, plugs [BPR7ES] gapped at .024)
3 Inch Catback Exhaust
NGR Performance Type S BOV
T25 and 450CC stock injectors
Greddy Profec B Spec II
Greddy Full Auto Turbo Timer
AutoMeter Carbon Series Boost Gauge (as a secondary check against what the EBC is displaying)

Any guidance would be appreciated.

 

[habitatguy187]

Any guidance would be appreciated.

Guide yourself into selling your EBC on ebay and buying a MBC, my friend's boost controller can never hold boost correctly, it always fluctuates from 20-22psi. And as for what I've read online a lot of people have problems with them holding boost correctly. Guess that's why all the big dogs buy Hallman Pro's instead of using an EBC.

 

[knochgoon24]

The T25 will lose boost in the top end. It's just too small. I"d drop to 6psi by 7200k in my car.

 

[habitatguy187]

The T25 will lose boost in the top end. It's just too small. I"d drop to 6psi by 7200k in my car.

According to member Pboglio, if you get the FP (I think it was???) wastegate actuator the t-25 will hold it's boost up top quite well. I'll PM him to get the real details in here.

 

[CanadianTSi]

If your hitting fuel cut on a T-25 I would check for boost leaks.

 

[habitatguy187]

If your hitting fuel cut on a T-25 I would check for boost leaks.

Especially at 12-14psi! Totally overlooked that.

 

[LandoAWD]

Check that knock-off BOV. BLT.

 

[pboglio]

According to member Pboglio, if you get the FP (I think it was???) wastegate actuator the t-25 will hold it's boost up top quite well. I'll PM him to get the real details in here.

I think I held 18 psi dropping to 15 psi on stockish mods. Definitely never had a complaint about the boost dropoff to be honest. I mean, its a T25 for pete's sake. I get boost dropoff on my EVOIII 16g. Just enjoy the midrange torque.

It has alot to do with the big wastegate actuator flapper all the T25 and T28 turbos come with stock, and the super weak wastegate actuator spring. I used the Hahn Racecraft T25 wastegate actuator upgrade and that thing worked great for holding more boost. Plus the spoolup improvement and harder torque hit when boost comes on.