Ive been reading about the profec II and some people are saying that it can only raise your boost to double what the wastegate is set at. does this sound right? or are they wrong? anyone that has experience with the profec know? thanks

-Chris

I have a 5psi actuator on mine now, I run 11-13 psi daily. So it will at least go as high as 100% more.

The Profec B doesn't care what boost your wastegate is set at. All it sees is pressure at its internal sensor and at its solenoids. If the boost is below the maximum level that the sensor can read and below what the solenoid can control, you will be fine. From Greddy's info, the max capacity of the unit is 300 kpa (about 28.8 psi boost). As for whether the sensor or solenoid maxes out first, I can only speculate.

Corbin

'95 ESI-T
Now with more power and fewer leaks



Gimme fuel...Gimme fire...Gimme that which I desire

Originally posted by Corbin
The Profec B doesn't care what boost your wastegate is set at. All it sees is pressure at its internal sensor and at its solenoids. If the boost is below the maximum level that the sensor can read and below what the solenoid can control, you will be fine. From Greddy's info, the max capacity of the unit is 300 kpa (about 28.8 psi boost). As for whether the sensor or solenoid maxes out first, I can only speculate. Corbin '95 ESI-T Now with more power and fewer leaks Gimme fuel...Gimme fire...Gimme that which I desire

ok thanks, those were my thought exactly, how would the wastegate affect the profec's solenoid. ok, thanks for confirming my speculation on that claim

-Chris

Originally posted by Corbin
The Profec B doesn't care what boost your wastegate is set at. All it sees is pressure at its internal sensor and at its solenoids. If the boost is below the maximum level that the sensor can read and below what the solenoid can control, you will be fine. From Greddy's info, the max capacity of the unit is 300 kpa (about 28.8 psi boost). As for whether the sensor or solenoid maxes out first, I can only speculate. Corbin '95 ESI-T Now with more power and fewer leaks Gimme fuel...Gimme fire...Gimme that which I desire

page 32 of the GReddy manual "Controls boost up to 300kPa (43.5psi) (This may vary on different turbo systems)"

Originally posted by CarbonFiberRST

Originally posted by Corbin The Profec B doesn't care what boost your wastegate is set at. All it sees is pressure at its internal sensor and at its solenoids. If the boost is below the maximum level that the sensor can read and below what the solenoid can control, you will be fine. From Greddy's info, the max capacity of the unit is 300 kpa (about 28.8 psi boost). As for whether the sensor or solenoid maxes out first, I can only speculate. Corbin '95 ESI-T Now with more power and fewer leaks Gimme fuel...Gimme fire...Gimme that which I desire

page 32 of the GReddy manual "Controls boost up to 300kPa (43.5psi) (This may vary on different turbo systems)"

well what does that last part mean? "this may vary on differnt turbo systems"? is this just talking about the turbo's overal capacity to boost, or what?

EDIT: on page 17 of the tech guide on greddy's site, it says "100% will boost up to the turbocharger's/wastegate's limit"

i assume this is saying up to the most the turbo will boost or the most the wastegate will stay closed before the manifold pressure pushes it open, because i think it was stated in there somewhere mentioning that... is this right?

Originally posted by GSGoinFast
how would the wastegate affect the profec's solenoid.

The solenoid is just an electrically driven valve. The default condition for this valve is to connect the pressure input line to the wastegate actuator line (if the valve fails, you will not overboost). So, an electromagnet must push the valve open to close the pressure input line and open the wastegate actuator line to atmosphere. That electromagnet can exert a finite amount of force on the valve. If you continually increased the air pressure in the pressure input line, you would eventually overpower the electromagnet and force the valve back to its default condition. Who knows what pressure that is or if the lines would pop off before that even happened?

You've got the right idea on the turbocharger/wastegate limit. At least on my S16G, the wastegate actuator has to fight the force of the exhaust to keep the exhaust from bypassing the turbine. The wastegate actuator can exert a finite amount of force on the bypass valve. It is possible that the exhaust could put enough force on the bypass valve to push it open. That would be the limit of the wastegate. The turbo will have a limit too. It will reach a point where it cannot pressurize the incoming air any further.

Corbin

'95 ESI-T
Now with more power and fewer leaks



Gimme fuel...Gimme fire...Gimme that which I desire