boost controller??
 

Well i have been reading alot about boost controllers lately seeing as how i am gonna need one probably when my build is done in about a month. My question to those who know about them and have experience with them is.. What is necessary? I see manual, i see electronic, and then some use different methods of controlling the wastegate.. There is also a pretty big range of pricing on these things so i wanna make sure i am not overspending. Any advice on brand or model is welcome as well.

If it matters, the turbo i will be running is a BNR stage 2 with ALOT of supporting mods (fuel, standalone, manifolds, TB, ported motor etc.)

The biggest thing to remember is that the easier it is to tune the controller, the less adjustability/compensation you will have. Things to remember:

You can't "lower" boost with a boost controller. Your wastegate has to flow enough and have the proper spring pressure.

A manual boost controller will get the job done, but has more variation with the weather than an electronic. How much variation just depends.

Not all external boost controllers are the same. A lot of them are very similar, using a similar solenoid and similar types of settings. But there are some "outliers." The HKS EVC uses a stepper motor instead of a solenoid. The Profec S has simple knobs to control the boost and isn't as adjustable as some options like the Blitz, Turbosmart, Profec Spec II, etc. The AEM Tru boost is a "dumb" solenoid driver without any kind of self correction or feedback.

There are multiple types of plumbing you can use with any electronic boost controller. The controller is usually just a solenoid driver, it pulses the solenoid coil on or off. You can use that solenoid in many different ways. So when you read "oh, hook it up this way, put this line here." Well that way may work, but there isn't always one "RIGHT" way to do it. I have a very unusual boost control plumbing setup on my T04R with external wastegate. But I made it work for me.

Standalones usually have the most adjustable boost controllers (weather/IAT compensations, boost by gear, closed loop control strategy), but they can be the hardest to tune if you are trying to use all those features.

I would check into the standalone's capability to control boost, you can save yourself alot of money and only have to purchase a solenoid and then using your standalone to take care of it all.

I removed a greddy and went with the built in option offered by my Wolf.

When we first tuned the car my used HKS was bad so we put a manual one in, when I retuned with the wolf I gained 30hp across the powerband because the boost did not bleed off early like it did with that particular manual controller I was using, I had run a greddy in between there and it did control boost very well and was very adjustable, I just wanted to simplify things

If you have no intention of ever messing with your standalone (just want to take it to a tuner and forget about it) then using an external EBC may be a better option. That way it'll be easier for you to make adjustments.

I have a greddy profec-B... you can find them used on here for 300 in great condition.....
http://www.studiotsang.com/profec.jpg


Manual controller : you have to get out of the car to set it.... There normally mounted under the hood and have 1 setting.

Electronic Controller : normally mounted inside the car and can have various settings and features. Most have a hi & lo boost feature.

You dont need a Electronic one....
Lets say you want to run 14psi. and nothing more, nothing less... a manual would b great.

A Electronic one allows you to change boost with the press of the button.

ie. Mine is set on 7psi when the controller is off (driving locally). then lo boost is 10psi..... and then hi is 14........

^^ now that you mention it i am looking at one from someone on the forum for 150 and it is a profec b... But if my standalone can get the job done even better then i dont exactly have money to be throwing around for the hell of it lol. Thankfully i am not the one who will be tuning the car, my mechanic will be taking care of it. I guess maybe i should ask him what he prefers? I wouldnt mind having a low/high boost option that has always caught my eye..

which standalone do you have?

I have a Power FC ECU.... and so does my buddy... he uses that to control boost. Its cleaner and alot more simple for sure. the only problem with the Power FC is controlling boost past 14psi.... but if your staying below that its perfect...

i think he said wolf???

is it the power FC that has a problem past 14psi or that solenoid he is using?

Once the controller is set I see no reason to touch it again unless your set up changes

^ good point..... something to think about if hes going to let the standalone do it

have a Gotec standalone.. It is a brand that is just starting to make its mark in the states.. I started a thread on ti a while back but not too many people could provide much feedback https://www.rx7club.com/2nd-generation-specific-1986-1992-17/gotech-ecu-876744/

In that thread Aaron said that there's no way to really mess around with the software in an offline mode, so there's not a whole lot of advice I can give on its boost control features.

The Power FC itself has no problem controlling boost past 14psi. I have done EXTENSIVE testing on PFC boost control and have written multiple articles in the third gen section on it. Sequential twins have their own issues with the plumbing as far as cranking the boost over 14psi. But if you are single turbo or nonsequential, you can run boost has high you are want as long as you know how to hook up the solenoid and wastegate correctly for your given boost level. I am running over 16psi with a Power FC controlling boost. A 3 bar MAP sensor is required for these higher boost levels.

And FYI... on electronic boost controllers you can still get fluctuations in extremely cold weather. Only standalones with air temperature correction capability can prevent this, such as the AEM EMS (Power FC can't do it unfortunately). There is usually a solenoid duty cycle vs IAT map to use, same as the factory boost controllers on STi's etc. No external boost controller can make air temperature corrections.

NICE!!! if u dont mind PMing me a link... ill be sure to forward it to my friend.... It should be some every useful info.... :icon_tup:

- Dennis

Not entirely true. You can get a two stage manual like I have from Turbo XS which lets you select a high and a low that have to be tuned with the hood open (not a problem if you are tuning on the dyno).

My tuner prefers the manual setup as it is simpler thus there are less things that can go wrong. However, my car is set up for track use so the simpler the better.

A while back GRM did a test and the Brofec B came out ahead as far as building boost quicker and no spike.

I haven't used an EBC, but the advantages of having a good one can be very useful. Some such advantages have already been mentioned, like reduced spike, building boost faster, ease of adjustment. Another big one is consistency. A manual boost controller, though simple and cheap, can allow significantly higher boost levels to occur when the air is much colder while at the same setting. Another is staging. Maybe you don't want full boost until you're past 'x' RPM.

So anybody recommend any specific models or brands? Please include why you recommend it thx.

Profec S (or old profec B) if you want easier to use, Profec Spec II if you want something with more adjustability. AVC-R if you want a LOT of adjustability but tougher learning curve.

AEM Tru Boost... well only advantage is the compact gauge design and the price, it is an open loop boost controller that will not adjust the solenoid duty to smooth out boost fluctuations.

I'm pretty sure I've seen MBCs that are mounted inside the car and the vacuum hoses are just routed into the cabin. I don't know how well that would work though. I'd love to eventually have it ran by a standalone, sounds awesome!

Like I said, I use a dual solenoid manual boost controller and the switch to go between low and high is in the car. The switch is in the car, so I guess that makes it a partial manual controller. My car is mainly a track car so I am happy with that level of control. I will not be tuning it on the track, so I prefer to just set it and forget it.

My current setup is not boosting past 15psi, but I do not know if that is due to my wastegate actuator or the boost controller not being able to hold past 15. Either way, I'm happy for now as I am was building a track car with decent power. Eventually, I may get the hp bug and upgrade my turbo etc, but for now I'm happy with the BNR stage 4.

I figured it would come down to the Profec's.. Im kicking myself for passing up an OG profec B for 150 bucks lol.. I would like to have low and high boost, is there any difference in reliability between the original, II, or S?

The Profec B uses a stepper motor kind of like the HKS EVC, instead of the more common solenoid valve used on the Apex'i and the later Profecs. Since the Profec B is discontinued, it may be hard to get a replacement stepper motor should it fail (I'm not sure if that's common or not).

The Profec S has the same knob style control as the Profec B but it uses a 3 port Denso solenoid valve, just like the AVC-R. The Profec Spec II also uses this solenoid valve but the controls are a little different. You set the base solenoid duty cycle as an actual number. You set the actual pressure at which the wastgate is allowed to crack open, and you set a numerical value for the level of gain (how much the EBC is allowed to adjust the duty cycle to stabilize boost). It will take you longer to figure this out, but you can make more precise adjustments (although not as precise as the AVCR).

On the Profec S and Profec B you turn knobs until you're happy enough with what you see on the boost gauge. It's more straightforward but less precise.

there are other brands of boost controllers out there like the Turbosmart and the Blitz. But they're very similar to the Profec Spec II... same type of controls.