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Aftermarket Boost Control Solenoids

99K views 20 replies 12 participants last post by  arcticscythe 
#1 · (Edited by Moderator)
Factory boost control relies on a flimsy, inefficient solenoid. When boost levels are increased over stock, the factory actuators fail to properly meter boost. The resulting spikes, dips and erratic response can damage your engine and spoil the performance gains. An upgraded electronic boost control solenoid allows a much lower waste gate duty cycle to produce higher boost levels giving tuners better control and decreasing spool time. Now lets discuss why.

Stock 2-Port Operation
The stock solenoid is part of the stock bleed-based boost control system. When the solenoid is off (closed), pressurized air from the compressor is fed straight into the wastegate control. Any increase in compressor pressure beyond the rated pressure of the wastegate control results in the wastegate being opened, preventing buildup of boost.
When energized (opened), air is allowed to bleed off the compressor-to-wastegate line by way of a “T” connector. This prevents the wastegate from seeing the full compressor pressure, allowing boost to build. Most model years include a restrictor pill in the hose connecting the compressor to the “T” which meters the air for the stock ECU calibration.
While the stock system operates adequately, it can lead to problems at higher-than-stock boost levels. Since the bleed system is sized for the stock turbo at stock boost levels, it is typically incapable of correctly metering air at higher boost, allowing the wastegate to see pressure and open before intended.
Additionally, since the wastegate is never completely cut off from seeing compressor pressure, it can open at low boost levels and inhibit boost buildup. Ideally, the wastegate should remain entirely closed for fastest boost buildup (as all exhaust is then forced through the turbine).

Aftermarket 3-Port Operation
A 3-port solenoid does away with the bleed-based system, explicitly shunting air from the compressor to the wastegate, or compressor to vent (or back into the intake post-MAF, OEM-style). Drawbacks of the bleed-based system are thus eliminated, with the wastegate seeing literally no pressure when the solenoid is energized, to seeing all of the compressor pressure when the solenoid is de-energized.
Now able to totally control the opening and closing of the wastegate, the ECU is able to control boost with greater precision and reduced response time.

This modification will make your current boost map OBSOLETE. You MUST retune boost. If you have no way to tune your boost control tables, you should NOT do this mod.

There are a lot of options out there. Some are a little easier to install than others, but all perform the same function. I have done some research in the solenoids available. If you do a little looking around you can find reviews for each of them:

GM 3 Port ~$65:
GM boost solenoid for Typhoon, GM Part # 1997152($48.89) Pigtails, GM Part # 12102747($15.40)
Full DIY: GM solenoid install (56k warning) - NASIOC
Alternately: ACDELCO solenoid part # 214474 and ACDELCO ABS modulator pigtale part # PT374

Prodrive BCS ~$125:
https://www.stiperformanceparts.com/product.php?productid=2318

Perrin 3 Port ~$100:
Perrin Performance - Boost Control Solenoid

IxizConcept IxizEBCS ~$68:
IxizEBCS

Grainger 3 Port ~$30:
Pneumatics & Hydraulics > Valves > Solenoid Air Control Valves > Valve,Solenoid,1/8 In : Grainger Industrial Supply

Grainger 4 Port (for EWG) ~$57:
Pneumatics & Hydraulics > Valves > Solenoid Air Control Valves > Valve,Solenoid,1/8 In : Grainger Industrial Supply
NASIOC - View Single Post - Full DIY: GM solenoid install (56k warning)

GrimmSpeed 3 Port ~$110:
GrimmSpeed

MAC 3 Port ~$26:
MAC valve part # 35A-AAA-DDBA-1BA

I took info from various sources including the installation instructions from GrimmSpeed and Perrin, and put it together for this article. I put it together because I couldn't find a good article that told why the boost control solenoid was a good modification.

**** This guide is my made up of my own opinions and the knowledge that I have gained in the past 3 years of WRX ownership and modification. I take no responsibility for damages or legal issues from following this guide. The decision and responsibility to proceed is yours and yours alone.****
 
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#6 ·
One thing im not completely clear on...
im buying a 3port and i'm running the AP V2. It seem that some people are saying the AP will recognize the 3port but does that mean i need to re-flash with it on? or have someone completely redo my maps?

i guess what i'm saying is exactly what is required to run a 3 port bcs when using the AP as far as maps are required!? it doesnt seem that there are any CObb maps on the site for use with a 3port?
Thanks
 
#9 ·
i havent purchased it yet. i was going to do it today but i'd like to have a conversation with my local tuner shop and make sure they're good with AP custom mapping first. other wise i'll put it off for a bit. the car is running great, if the load changes the boost can be a little fluttery but other than that its good. the grimmspeed 3 port is likely the one i'll go with. i'm pretty happy with the power the car makes right now so i'm looking to do some good support mods just to ensure she's healthy! ie 3 port, fuel pump, maybe an intercooler. then next summer drop a 16g and some pinks in..
 
#15 ·
Wonder if we should throw in the GMBCS/MBC hybrid boost control. I have been thinking about this, but haven't found much on it. Anyone here doing this, likes, dislikes and tuning issues?
 
#16 ·
So I decided to jump and try the hybrid boost controller idea. Well to say the least this has been a bit of a pain to figured out. After tinkering with the maps ALOT, I managed to get it to pull up to 10psi without a bit of knock all the way to 7800. I will experiment with it a bit more today and see what I can come up with.
I have a bit of an idling issue at the moment and have to look at my fuel trims and see if I need to fix something I may have missed since I started this using a factory map...:( I also had to use half values as it seems I am currently out flowing the stock MAF...Time for a bigger housing....woo-hoo!!Thumbs Up
 
#17 ·
Hey guys subie nubie here just bought my 08 WRX and am about to order a Cobb catted DP and get a tune from a local professional other than that my car is stock. Would it be back for my car in any way shape or form or not recommended to pick up the grim speed 3 port? Thanks in advance guys
 
#21 ·
If you can I would bring a tool bag and install your EBCS right in front of your tuners shop. Or like the guys suggested have them email you a limp map to get you there safely. and just a side note. You dont need the down pipe to benefit from the extra control of an EBCS. Just a proper tune will do.
 
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