Reddy

Since I now have some free time on my hands I thought I'd contribute to this site by doing a writeup on boost controllers. First off, a boost controller CANNOT lower your boost lower than stock. The spring in your wastegate is what sets the minimum boost pressure and a boost controller cannot change the tension of that spring. The boost controller simply controls the amount of vaccum going to the wastegate to up the boost. There are two types of boost controllers, manual and electronic. The MBC (manual boost controller) is cheaper and usually cannot be adjusted from inside the car. The electronic ones are more expensive but can be adjusted from inside the car. Now with the basics out of the way here are your options for boost controllers;

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Homemade Manual Boost Controller

Since this is HMT we'll start out with the cheap and ghetto.




This is a MBC that you can build yourself. It may not be the prettiest but Beau is using something similar in his low 11 second (and dropping) CRX. It is effective and cheap which are good things, however these can be pretty unreliable. Here's how to build it;

http://www.geocities.com/chmwatson/FAQs/mbc.html




This is a Greddy unit that works on the same principal, it just looks alot prettier.



This is the Turbo XS version which is probably the most popular. Its a dual stage so you can set a low boost setting and also have a high boost setting that you can engage with the flick of a switch.


Again the major downfall of MBC's are that they are not as accurate as EBC's, and you have to get out of the car and make adjustments underneath the hood. A dual stage is by far the best choice in MBC's

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Electronic Boost Controllers


Now these are more expensive than the MBC's but sometimes they're worth the extra money. With an EBC you can make changes inside the car, they are usually more accurate, and on most you can adjust the "gain" of the wastegate. This means you can adjust how slow or fast the wastegate opens which means you can adjust the wastegate to stay closed longer and get a better spool time.




This is the Greddy Profec B and is probably the most popular EBC becuase it is one of the lowest cost EBC. It has a high and low boost setting that you can adjust from inside the car, and you can also adjust the gain as well. They did redesign it to this;



I haven't used it yet so I don't know how improved it is from the old version.



Now onto my favorite boost controller, the Blitz SBC-ID. I like this better than all the other EBC's with displays cause it works in PSI instead of only bar or KPA like the fancy Greddy one.



This is what it looks like. What I like about it is that it has a boost gauge built into it and it will hold and display the peak boost pressure that you reached. This way you don't need to guess about how much boost you hit. The boost can be adjusted by that **** in increments of a tenth of a psi.




These are some of the features it has. If you buy the speed meter or something you can link this controller to that and control boost by what speed your at, basically a ghetto form of traction control.




Now here's how you more accurately adjust boost. It has 4 channels so that means you can have 4 different boost maps. All EBC's run off of % over stock wastegate pressure. So when you set the controller to say 9.9, thats 9.9% over preset wastegate level. So the "set" feature is where you actually up the boost. The gain is how fast you want the wastegate to open. on internal wastegates I usually set the gain to 100% but on external wastegates its alot more sensitive. If you would set the gain to 100% the wastegate would not open soon enough and you'll get massive boost creep. So find a happy middle.





This is where you set your boost limits. It has an audible warning and the screen turns red if you overboost it. The limiter sets how much boost or how fast it will take out the extra boost to return it to the preset limit. I've never had any types of boost spikes with this boost controller.





I also like how thin it is, its very easy to mount places.




This is another box that you need to mount, most people put it under the dash but I mounted it where you can see it since it did cost alot.


It also has a playback feature where it records and you can see how you run went. You can also display the boost in graphs and a bunch of other ---- that I left out cause HMT's attention span is pretty short.

Now which boost controller is right for you? Well it all depends on your setup and what your goals are. Yeah EBC's are real nice but they're also real expensive some MBC's are better for some applications. The only reason I bought the best was becuase every car I ever owned ended up turbocharged so this controller goes with me from car to car.
If anybody else has any experience with boost controllers post them in here...



P.S. Hey Quadrine, I ain't preching from it, I'm writing the ----------er :P

projekteg

i've got this one, works great, and you can mount it in the car unlike most other mbcs, well technically, you can put any bc in the car, you just have to extend the vacuum lines. this piece is very precise, i've not had any spikes at all and is adjustable as little as 1/4 psi.

s1ngle

ok, so if you can't lower boost than the stock wastegate using an MBC, then how do you do it?

projekteg

if you have an external wastegate, you have to buy a different spring. if you're using an internal wastegate, you have a couple options 1) you can get a different actuator that is set at a lower level 2) you can extend the actuator arm which lowers the boost. this is why i reccomend getting a very low psi wastegate spring/actuator b/c you can always raise it via a boost controller, but it's not so easy to lower it.

Reddy

The longer the vac lines to the boost controller, the slower it is to respond

scttydb411

you forgot the bleeder style mbc...much like your first one, but instead of a ball, spring, and adjustment nut it has a needle valve you can open more or less to vary boost. no moving parts to get stuck and overboost. fully closed so no pressure escapes=stock wg setting. more and more you open it the longer it takes for boost to reach the wg actuator since you have to build more to compensate for the pressure bleeding off. it can only be used on turbo that have the pressure line/nipple at the compressor outlet (it goes inline between that and the wg nipple). if you try and use it from a source at the intake manifold it mimics a vac leak at the throttlebody/intake.

i'll try and get some pics of the one i made. it seems to be more consistent and reliable than a ball and spring type as well.

alwaystootall

im using the $8.00 ebay boost controller :P.works good for me. i did have to cut a little of the spring to get it to work right for me. no boost spikes,boost goes up and stays right where it should.
..The boost controller simply controls the amount of vaccum going to the wastegate to up the boost...,is it the amount of vaccum it sees or the amount of boost?

quadnie

damn turbo bible thumpers

It's about time to install one on the GST so I'm thinking hallman pro or maybe that Turbo XS one.

Oh and don't forget how Beau's HMT MBC failed on him!

quadnie

Anyone have any experience with the Hallman pro? For some reason I thought that the Hallman pro had the function of reducing wastegate creep (faster spool) but I haven't found any data to back that up.. I swore I did like 6 months ago.. looks like the Turbo XS High Performance mounted under the hood is going to be the way to go. I'm really after a quick spool time with upped boost on that T25. $110ish on egay isn't that bad

baldur

It's a common false beleif that ball-spring type boost controllers keep the gate closed until the set boost is reached. This is completely false, they keep the gate closed until the threshold is reached, they just offset the wg actuator pressure by a certain amount. Bleed valves however scale the wg pressure.