had Profec b spec II on last car and it was great, my friend has one on his 200sx, that runs 12's(not bad for the car).

i have yet to put it on my evo, cuz i have a few issues to sort out with the dealer before i void my warrenty(tranny issue) but it will go on the evo, if it works as well on the Evo as my last car, it will be great.

i think its absolutely simple to setup, just need a stright road to do some pulls, start low and work up, if its connected right you are golden, if its not right u will know it, but what controller wont be f'd if its not connected correctly?

 

for a daily driver i have the hallman and ill tell u what, its great imo. holds boost, nice peice, and easy to use. now if u want to race your evo then u are going to be spening a lot of money on parts anyway so just get the ebc. but there are many drag cars that use mbc's.

 

Do not flame on me:

Does the EBC have a mechanic device to change the boost pressure? or does it change only by electronic inputs?

 

I'm in the process of re-inventing my boost control set-up so I though I'd chime in.

First - The Hallman is good item, but it has limitations on my car - with it the boost spikes up then tapers. I believe the problem is that my car has quite a few mods, and in the upper RPM I move quite a bit of air. For refference if I use my XEDE and create a flat boost table (all 100%) my car does the same thing. One thing worth noting is that in my current set-up setting the OEM controller for 100% lets my car spike to 23 lbs and then taper back to about 16 lbs - almost exactly the same behavior as the Hallman. I can dial in more boost with the Hallman, but I still have to worry about the spike.

What I am currently working on is developing a method of incorporating both the Hallman and my OEM boost controller (controlled by my XEDE) to deliver a smoother curve. I'm looking for about 22 or 23 lbs peak (depend on what the engine prefers) with a taper to 19 or 20 lbs - with the primary control being the OEM boost controller. I'm also hoping that I can push the total possible boost higher than OEM controller will allow.

I have tried a couple of the methods listed here and in the Vishnu forums for doing this, but none of them have worked correctly in my car. That said, I think I may have the answer - I'm heading out right now to do a bit more tesing. I'll let you know a few of hours if it works.

Research is fun!

 

Electronic boost controllers use an electric selenoid to drive a mechanical valve. The actual boost settings are generally controlled by telling the electroncs how much to open or close the valve at a given speed and/or RPM. This information is provided by entering a table or other form of user input.

 

OH YEAH!

I just got back from some initial testing and the results are spectacular! With the car's OEM EBC set to allow 10% boost my car was hitting .78 BAR at max boost with the MBC set to minimum boost. With the same EBC settings but the MBC dialed for maximum boost the car broke 1.5 BAR in a quick test.

The result is that I will be able to set the manual boost controller for maximum desired boost at redline and use the OEM EBC control table in my XEDE to set the desired boost at any point on the curve. And I'm no longer limited to 16-17 lbs at redline.

I'm out for tonight. Tomorrow try to hit the dyno and re-tune the car - if that happens I'll post some results.

 

sounds good....thanks for the input! definitely let us know how it turns out!

 

i like my spec II. i only run 20 psi on 93 and 23 on 100, but the spec II holds it to redline if you set the "set gain" high. if you set boost to hit earlier, lower set gain, you might loose a psi by redline. i like it a lot because temps change enough in Chicago to change the boost by at least full psi from afterntoon to night or morning to afternoon. i also find it conveinent that there are two settings as third gear boosts higher then 1st. maybe it starts raining and you turn down the boost to save some gas and for safety. halman can't do that. one thing you need to know is the spec II boost gauge is inaccurate. it would be in your best interest to purchase one with it. get a cheap $60 defi gauge. or there is a wideband datalogger group buy that you can get a aem medical grade boost gauge with. the most accurate boost gauge available.

 

The results are in and ... mixed. While I'm able to do a better job of controlling both spike (with the EBC) and taper (via the mbc) the set-up still won't let me dial in as flat a curve as I had hoped.

Right now I have the car set for about 22 lbs of boost from 3K to 6K and then tapering to about 17.5 lbs at 7500 RPM. It's a slight improvement over my previous set-up but not as good as a quality standalone EBC should be able to deliver.

The set-up did gain about 10 ft/lbs of torque at peak boost and about peak 10 awhp by doing a better job of managing both the spike and the taper, though. The torque peak came from seeing less timing pull at peak boost. The HP improved because of the improved boost curve. Overall this will improve things across the entire band, but only slightly.

 

thanks for the info........ i purchased the profec b spec 2 and will be installing it in the next few days. i'll let you know how it goes