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i have in the past been flamed for posting that the PFC boost controllers are fairly average so when the opportunity arose to do a back to back test i could not resist.

I have the done the comparison below on power as it seems people take more note of power than torque... i dont know why. For those who want the real story i have included the torque graphs as well. :P

Over the years i have seen excellent gains with a good ebc i have even seen midrange gains in the vicinity of 50rwkw, i know this is a lot and to be honest it was on a car making well over 300rwkw.

The example below is what i consider an average skyline setup and it gained between 10rwkw and 32rwkw between 3000rpm and 4300rpm...right in the area you need it most.... more importantly torque at 4000rpm rose by 80nm just by using a boost controller with GAIN control.

Below are two graphs one is power and torque graph the other is a boost graph;

Thin red line is a manual boost controller set to 1.3bar (i have not included power runs as it is obvious it would be way lower)

Thick red line is PowerFC boost controller, holds good boost all the way to red line and makes the following power;

62rwkw @ 3000rpm

80rwkw @ 3500rpm

120rwkw @ 4000rpm

180rwkw @ 4500rpm

200rwkw @ 5000rpm

240rwkw @ 6000rpm

269rwkw @7000rpm

Thick green line is Blitz IDIII boost controller with correctley set gain, holds good boost all the way to redline and makes the following power;

74rwkw @ 3000rpm (12rwkw gain)

90rwkw @ 3500rpm (10rwkw gain)

152rwkw @ 4000rpm (32rwkw gain)

180rwkw @ 4500rpm

200rwkw @ 5000rpm

240rwkw @ 6000rpm

275rwkw @7000rpm

Thick Blue line is Blitz IDIII boost controller set at 1.25 so it cant be compared directley but it shows just how much extra power and torque can be gained with the CORRECT GAIN setting in your boost controller. If this 1.25bar was runj with the PFC boost controller it would have made the same peak power but would have followed the red line... thus missing all the extra midrange torque and power;

74rwkw @ 3000rpm

90rwkw @ 3500rpm

152rwkw @ 4000rpm

190rwkw @ 4500rpm

218rwkw @ 5000rpm

250rwkw @ 6000rpm

293rwkw @7000rpm

boostresponsepower.jpg

boostresponse.jpg

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We also discovered this and documented it on here a few years ago...we actually made the same power with less boost switching from AVC-R to Blitz ID-III.

A few AVC-R lovers out there were most upset at me having a go at their bright blue toy.

Excellent thread to back it up.

Well done Trent...top stuff.

Edited by DiRTgarage

With regards to setting the gains Trent, do you just pick your desired boost level that you want to hold, then just keep increasing the gains to the maximum setting before it starts to spike boost?

:wave:

yeah i had the 180sx folder open when i printed the skyline graphs.... my fault

Car is a R33 with unopened rb25 and a custom 8cm T67 kit i ordered from trust for it. Final result was 310.1rwkw @7200 and 427.9Nm at 6100rpm (makes 392 @ 4100 though so its got quite a broad torque curve.)

If you could pick any ebc would it be this or is there something even better Trent?

Any Blitz dual solenoid in my experience works the best (gain wise), i have plenty of graphs i could post up but i rate the boost controllers as follows;

1. BLITZ dual solenoid (type R, ID, IDIII or I-color) But i find the i-color is a bit too gadgety.

2. Gizzmo MSIBC (black with blue display) (awesome controller with closed loop boost control and cheap)

3. TRUST Profec b SPEC 2 (great controller, easy to set up)

Did the customer comment on any difference on how the car drives?

100% this car is used ALOT (daily) and spends alot of time doing hills runs and we have been developing the car for response so he knows it inside and out, im pretty sure it just pulled 1.45 around winton which is not too bad considering it was his his first time at winton on street tyres. The car has actually has had two turbo setups on it previously gt30 int gate and a gt35r both were not up to scratch (too laggy).

Let's dig a little deaper than the "this is better than that" simplicity, because there is no magic in a boost controller. What's happening here is the wastegate is opening earlier when controlled by the PFC BCK in comparison to the same wastegate being opened by the Blitz IDIII. Looking at the boost curve it indicates that even as low as 0.2 bar there is a difference. Think about that, at less than 3 psi there is wastegate creep. That tells me the wastegate actuator spring selected is far too small or it's not delivering its rated pressure. This diagnosis is supported by the manual boost controller (simple bleed valve?) trace which show the symptomatic over shoot and then taper off of boost as the rpm rises.

What we don't see here is what the maximum achievable boost curve actually is. What the turbo is capable of when there is absolutely zero wastegate creep. The only way to achieve that is to lock the wastegate closed and log the boost curve up to the target boost. Then you know exactly what is possible out of that engine/turbo combination. It is entirely possible that an even better result is achievable. As any experienced tuner will tell you, getting the right rate wastegate actuator spring is the first step in achieving decent boost control. That way the boost controller only has a small amount of work to do and hence the best chance of perfect boost control.

Personally I would spend $5 on the right rate wastegate actuator spring rather than spend $400 on a boost controller.

Cheers

Gary

Let's dig a little deaper than the "this is better than that" simplicity, because there is no magic in a boost controller. What's happening here is the wastegate is opening earlier when controlled by the PFC BCK in comparison to the same wastegate being opened by the Blitz IDIII. Looking at the boost curve it indicates that even as low as 0.2 bar there is a difference. Think about that, at less than 3 psi there is wastegate creep. That tells me the wastegate actuator spring selected is far too small or it's not delivering its rated pressure. This diagnosis is supported by the manual boost controller (simple bleed valve?) trace which show the symptomatic over shoot and then taper off of boost as the rpm rises.

What we don't see here is what the maximum achievable boost curve actually is. What the turbo is capable of when there is absolutely zero wastegate creep. The only way to achieve that is to lock the wastegate closed and log the boost curve up to the target boost. Then you know exactly what is possible out of that engine/turbo combination. It is entirely possible that an even better result is achievable. As any experienced tuner will tell you, getting the right rate wastegate actuator spring is the first step in achieving decent boost control. That way the boost controller only has a small amount of work to do and hence the best chance of perfect boost control.

Personally I would spend $5 on the right rate wastegate actuator spring rather than spend $400 on a boost controller.

Cheers

Gary

to be fair gary you are quite perceptive :D but for the sake of 95% of the readers i prefer to keep things simple and more akin to what many of the readers will experience in real world situations. :D

firstly we need to ignore the manual MBC graph because it was actually from the int gate garret setup on the car previously and is one of the reasons i did not go into listing direct comparisions, i should have made note but i figured people would ignore it as there were no power figure to compare it to..

secondly the wastegate has a .9bar spring in it as the customer wanted to run a low boost setting of 0.9 and a high boost setting of 1.25bar... as it is a stock engine after all. Of course in a perfect world we could have run a heavier spring to bring it as close to 1.2bar as possible but we had the issue of a low boost setting of 0.9bar... the best compromise was to adjust the preload on the trust gate to get the best boost ramp as possible without spiking at 0.9bar.

so yes the BLUE and GREEN graph shows the maximum possible boost curve for this setup, without resorting to locking the wastegate shut :D

on our application we were running internally gated HKS turbo's so no chance of changing the spring as they are sealed units.

The best and only option for us and many others was to invest in a decent controller...the Blitz ID-III is the best on the market in my opinion.

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