I just got a Profec B spec 2 and upon reading the manual discoverd that its not as simple as I figured it would be. Its not just a of setting a simple PSI figure, instead it wants a percentage.
Where/how do I figure out this percentage. I'm running a Garrett GT28RS with its stock wategate actuator and I think thats set at 7psi. How am I supposed to use that number to determine a %? Or is this more of a trial and error, drive it and turn it up, drive it, turn it up type thing?
Understanding the Profec B Spec 2
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Onizuka
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Well, they profec B spec 2 has a build in boost moniter. The manual pretty much explains everything (0% = boost controller lets the wastegate open as soon as posible and make the lowest boost, 100% makes the wastegate stay closed and make the highest boost posible)
The profec B spec 2 is more of a tuning device than a simple boost controler. You can dial out spike and creep, its totally awesome.
The profec B spec 2 is more of a tuning device than a simple boost controler. You can dial out spike and creep, its totally awesome.
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f150intally
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caliracer240
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OKay, heres what I have right now.
In Hi setting, I have 44% set, 10%gain, 100 set gain, 175 warning, 8% limiter.
In Lo I have/had 35% set, 10%gain, 0 set gain, 175 warn, 8% limiter.
In high mode, it seems to take boost a bit longer to kick in, but when it does, it really nails you back in the seat and will break traction hard at the top of first and way into 2nd. 14.7 seems to be the average boost, with a spike around 15.7. I've still got some toying around to do.
Now the odd part is in low, with 0 start boost which should make it boost slower, I actually got a spike of 16.3 and my max average boost was around 14 so something seems odd. I dropped the set% to 30, and set the start at 80 and now i'm sitting in the 12psi range.
This thing really seems to be luck of the draw as to what % you need to set to hit a certain boost level.
In Hi setting, I have 44% set, 10%gain, 100 set gain, 175 warning, 8% limiter.
In Lo I have/had 35% set, 10%gain, 0 set gain, 175 warn, 8% limiter.
In high mode, it seems to take boost a bit longer to kick in, but when it does, it really nails you back in the seat and will break traction hard at the top of first and way into 2nd. 14.7 seems to be the average boost, with a spike around 15.7. I've still got some toying around to do.
Now the odd part is in low, with 0 start boost which should make it boost slower, I actually got a spike of 16.3 and my max average boost was around 14 so something seems odd. I dropped the set% to 30, and set the start at 80 and now i'm sitting in the 12psi range.
This thing really seems to be luck of the draw as to what % you need to set to hit a certain boost level.
I had more time to play with it today. During the day my high settings were just a bit too high, average of 15.5psiand high of 16.3, with a 45% set, 10% gain, and 100 start. Tonight there was no one on the roads and it was cooler so I was playing a bit harder, and was doing an average of 15.9 with a peak of 16.6, so I turned it down to 40% and that seems to keep me within 15.5 consistantly.
NOW, I decided to try the low setting at 18% set, 10%gain, and 80 start, and I pulled an average of 13.4. Whats the deal here, I'm using less than half the high settings set boost, and I'm just barely lower. I've got it down to 12% now and its still hitting 12psi and peaking in the 13s. I had to get off the road because I saw a few cops go past and figured they probably heard me testing so I couldn't finish.
But something about this thing seems weird. There are no boost/vaccume leaks, all the plugs are removed from the solnoid, its hooked up correctly, but I still can't get consistancy of any kind, and when the temperature changed, it seemed like all the settings that I thought were perfect, are now useless.
NOW, I decided to try the low setting at 18% set, 10%gain, and 80 start, and I pulled an average of 13.4. Whats the deal here, I'm using less than half the high settings set boost, and I'm just barely lower. I've got it down to 12% now and its still hitting 12psi and peaking in the 13s. I had to get off the road because I saw a few cops go past and figured they probably heard me testing so I couldn't finish.
But something about this thing seems weird. There are no boost/vaccume leaks, all the plugs are removed from the solnoid, its hooked up correctly, but I still can't get consistancy of any kind, and when the temperature changed, it seemed like all the settings that I thought were perfect, are now useless.
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f150intally
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BaliLover wrote:Oh, I forgot to mention, I'm running a stock SR with a Garrett GT28RS and I believe the internal wastegate is an 11.5PSI unit.
BailLover,your limiter is set wrong. It needs to be set like this. if you want to subtract 8 % from your high boost set it at 36%. same for low boost. it is set the same way as set boost.
I am using the PSI, but it still requires that the set boost be done in %, the only figures that are set in PSI are the Start Boost(set gain) and the warning. It will also display the current boost and peak boost in PSI.
F150, I figured out the limiter was wrong yesterday and I readjusted it properly, but that wouldn't have anything to do with me not being able to get a stable boost.
I slept on it and realized that with my wastegate being an 11.5psi unit, I will never be able to get 10 PSI from it because you can't boost less than the wastegates setting with the Profec, so I'm going to set my low boost to 0% and see how that works.
F150, I figured out the limiter was wrong yesterday and I readjusted it properly, but that wouldn't have anything to do with me not being able to get a stable boost.
I slept on it and realized that with my wastegate being an 11.5psi unit, I will never be able to get 10 PSI from it because you can't boost less than the wastegates setting with the Profec, so I'm going to set my low boost to 0% and see how that works.