How well does the hydra control boost? What boost solenoid are you using?

With the Hydra. See my post in the UnOfficial Official Hydra thread. PM me if you want more detail than that, but it's pretty comprensive and builds off of Phils Tuning Guide #2. I can also point you to general "boost control" info if you need that.

Just from personal experience, don't get the Perrin EBCS to use with the Hydra. These two parts aren't working together for me. Getting ready to buy an AVCR to control boost...

Why would you buy an auxiliary ebc when you've got a powerful standalone?

Phil @ Element said most people using Hydra's use EBCs to control boost. Also, guy with an STi with almost exact same mods as me and also using Hydra EMS is using an AVCR instead of EBCS or nothing and said he is having no issues with boost and that he gained 7-10whp throughout his power range by optimizing his AVCR settings (with which you can control boost in each gear at each RPM...). After the problems I've had with the EBCS, I'm going to try an AVCR.

That's my reasoning...

TopSpeed in Atlanta tunes Hydra's and I've sen an STI there with the Perrin solenoid.
The Hydra controls boost mapped to *.*, but the factory solenoid is not as good as aftermarket solenoids.

I know the AEM crew has great success with a GM solenoid, perhaps that would help the hydra as well. If an ebc is required, that certainly tacks on a few bucks to the purchase price of a hydra.

Why would you buy an auxiliary ebc when you've got a powerful standalone?

The ability to change boost quickly is the main reason. As long as the ECU is mapped correctly to the highest boost you want to run, it's trivial to run the car at different levels. Changing the boost map in the Hydra to change how much boost you want to run doesn't sound like much fun.

The ability to change boost quickly is the main reason. As long as the ECU is mapped correctly to the highest boost you want to run, it's trivial to run the car at different levels. Changing the boost map in the Hydra to change how much boost you want to run doesn't sound like much fun.
Exactly. I guess I wasn't clear enough earlier. No question boost can be controlled with just a solenoid and the Hydra, but you need another map or a long time to tweak your map if you want to change boost levels. Also, it takes a while to set properly with the Perrin EBCS. Phil said it took him two hours just to get the EBCS and Hydra in synch before he could tune the rest of the car for one of his customers running this setup. I'm sure it can be done if enough time is dedicated. However, it seems alot easier to just start off with an EBC to dial in the boost (however I don't know this first hand since I don't have an EBC yet...). My comments are based on discussions with Phil and the condition my car is currently in with the EBCS...

Once tuned, an EBC can conveniently change boost levels on the fly by the click of a button.

I've been useing the stock solenoid for about 6+ months.

With what turbo?

The ability to change boost quickly is the main reason. As long as the ECU is mapped correctly to the highest boost you want to run, it's trivial to run the car at different levels. Changing the boost map in the Hydra to change how much boost you want to run doesn't sound like much fun.


I get it.

I guess with the AEM most people just set up a high/low boost switch to accomplish that; I assumed most standalones had a similar option. If you want more than two options, of course, an EBC is pretty much your only choice.

I'm not too sure if this is really bad for your car, but why not just run the power wire of the solenoid into the cabin and wire it into a switch. This would turn the solenoid on and off so you can either run boost by the wastegate or by the solenoid. Now you have high boost and low boost at the flick of a switch with the control of the hydra :)

That works perfectly if your wg boost is usable. Stock turbo, 7psi is a bit of a joke unless you just want a valet mode. But my 20g with a 15psi wastegate... That might work great.

I think the problem with aftermarket solenoids at this point is that I can only guide you in tuning them but I cannot provide you with a base boost map for anything but a stock solenoid. I give out a base boost maps for stock solenoids running most IHI based turbochargers. They pretty consistently have 8-10 psi wastegates and will rarely run over 20 psi in the upper RPMs ranges.

Since there are few people that can tune this system as well as I can, you may have difficulty tuning aftermarket solenoids, but it can be done well. I base this off of a few of my customers that are struggling to get their aftermarket solenoids dialed. I was able to but it took me a long time to find the sweet spot the first time around. I’m sure I could get it figured out in 15 minutes now but a novice should expect the worse.

Here is where we run into problems, one setup may have 10 psi gate, another 14, another 18, etc., and then differences in turbochargers is immense. Once you fully understand the boost control system you will catch on quickly. Think of it in the same way a sophisticated electronic boost controller works, you have a gate setting, a sensitivity setting, and then you have duty settings for various rpm points. Once you are able to translate this into “Hydranese” you’ll get it.

When I have a feeling the customer will get frustrated easily I usually recommend a good but simple electronic EBC. On my personal car I run the TurboSmart E-Boost. The reason I prefer this is due to the high resolution the Hydra offers for fuel and spark. I don’t need multiple fuel and spark maps, I just need different boost levels to control power output. So for instance on one map I can have the car running at 12.0 AFR at 15 psi, at 18 psi it can be 11.5, at 22 psi it’s at 11.0, and off course the spark map is also adjusted appropriately. All I need to do I reach over and hit the “Up” button on the boost controller and I’m done.

Thanks,
Phil
www.elementtuning.com

With what turbo?
Vf34. The reason why is answered in Phils post above.

It took me 3 weeks of off and on tuning to figure out the Hydra boost control but my situation was more complicated in that I had BC working then lost it, then got it back after some minor rewiring.

Phil's Tuning Guide is very basic and will get you started. I did a ton of experimentation to get the BC system working, then I did a ton more to really figure out how it 'ticked'. I posted almost all my tips in the Official Unoffical Hydra thread.

Another issue is present in this thread and it has nothing to do with boost control. I can only believe that Phil is not addressing it because he wants to limit himself to Hydra issues. The issue I'm talking about is the wastegate spring. While the spring is a component of the boost control system, its very passive and has nothing to do with the Hydra's control.

You can upgrade the spring to a stonger one or you can add a helper spring to the the actuator to "help" the one you have be "stronger". You can do this. The question is should you do this. Now we are in the realm of the judgement call. A strong enough WG spring will hold the the WG shut, period. You can boost to 40 psi with your little turbo. However, you will not being raising the amount of combustable air in a usable way and that is the point of turbocharging.

I have the stock VF39 in my STI and the Hydra. Now I run a maximum of 18 psi of boost but it tapers (wg blows open) down to 12.5 psi by the time I hit redline. I futz around with the Hydra parameters and now I can hold 13-14 psi to redline depending on the gear. I can put a helper spring on and hold more boost, but it's just hot air, and not in just the metaphorical sense, it's truly hotter air. Now I'm blowing hot compressed air into my engine--that causes all sort of problems, especially tuning problems. It make the intercooler into a wildly flutuating variable. If the IC is nice and cool it cools that hot air pretty well, if I'm sitting Seattle traffic and make a dash for it into the Express Lanes, well the IC has now become a IH, interheater.

Right now until the mother of all turbos darkens my front door, less is more. Add a spring or change a spring, and be prepared for true evil of tuning--inconsistent air or fuel flow.

The Hydra is extremely forgiving for those who overboost. Since the resolution of the fuel and spark map is so large, you can have fuel and spark mappings that your turbo will never, or only under bad situations, reach. I can boost to 22 psi peak, but I have to drop the AFR to 9 and run 10 degrees of advance. Got more boost, but no more power. Plus, I'm shooting gasoline out the tail pipe and didn't get to have as much fun.

Summary: pick you poison: boost or power or gasoline. Shuffle and pick again. It's funny I keep picking power all the time.

Vf34. The reason why is answered in Phils post above.
Yah, this is why I asked. When you said the stock solenoid was working good for you I suspected you had a smaller turbo. The stock solenoid used with the Hydra and a "smaller" turbo will work alot better than if you try to use this combo with a "medium" or "bigger" turbo...

More power to ya. Glad it is working out.

I'm just finished setting up the perrin BCS and the Hydra on my Green'd STi.

Stock settings of course were way off cause this thing is much more powerful then stock.

I ended up dumping Map 4 all the way to os across the board, made a run, got only wastegate of course and it came on real slow and weak. Max was aboyt 14psi.

Then went up to 20 max down to around 63% column then tapered it down nicely to around 3% at o% column.

This netted wastegate still. So I bumped to 30% as mentioned above, and smoothed the initial ramp up in.

Then beer call, so I'll let you know how this runs tomorrow.

I did initially set the PID integral for Boost control to 80 as Phil recommends for the Perrin BCS. I will not touch the PID, and hopefully won't have to until my boost on PWM4 is near ideal.

That's my story and I'm stickin to it...

Yah, this is why I asked. When you said the stock solenoid was working good for you I suspected you had a smaller turbo. The stock solenoid used with the Hydra and a "smaller" turbo will work alot better than if you try to use this combo with a "medium" or "bigger" turbo...

More power to ya. Glad it is working out.

FYI, I know the hydra is a different animal, but there's no reason the stock solenoid WON'T work, on just about any turbo, if you properly setup restrictor and actuator tension. (case in point, what it took to get my -11 to work on a stock solenoid).

I drilled the restrictor to 7/32's, and increased the preload, and now have a very nice and controllable 7-8 PSI spread using that solenoid.

Jorge (RiftsWRX)
www.ProjectWRX.com

Reviving an older thread.

I'm trying to tune my VF-36 EJ207 with Hydra and GM 3 port solonoid. Right now, I don't have a restrictor between the compressor and the 3 port. Following bboy's post, I used his values and had a reasonable boost curve that was just too low ( about 15 psig, which altitude corrected is about 13.2 psi). So I started bumping up the values in the 80% area of map4, but then I just get overboost and oscillation. I'm at the point now where increasing 67 - 85% areas of the map are actually generating lower boost values :confused:

This weekend I hope to put the restrictor in and start over.

I really don't want another control box wired in, but the AVCS is starting to look better all the time...