So which one is better at holding and controlling boost?

I know that ecu boost tuning is obviously more discrete, and is cheaper, but which method performs better??? I have been seeing a few threads with people having trouble with the Forge getting stuck or clogged or whatever...opinions???

Right now my car is stock....need to fix a boost leak at the moment my car peaks at 16.5 and drops to like 12 psi in 85 degree weather.

 

i would like to know too

 

There have been no issues with our Unos that we are aware of that are not easily remedied by a cleaning and reassembling of the boost controller or from improper installation of the springs inside the unit.

If there were to be any issue, however, not easily cured by these methods, we would obviously repair or replace the unit under our lifetime warranty, so there is really no risk. It willalways be covered. All you need to do is contact us.

In comparison to using the stock boost control solenoid, I don't see any reason to make the comparison at all.

On a stock ECU or even a flashed one, boost control through the stocl solenoid will be set at one predetermined number, and you will not have the ability to manually adjust it yourself unless you have access to the ECU to make changes to the programming. Even then, if possible, you have to program every perameter like boost onset (spool), taper, etc.

A manual boost controller offers you the ability to manually adjust boost levels without having to manipulate perameters inside the ECU every time you want to make an adjustment. Our unit is setup to provide quick spool as well as limited taper (both of which will depend on wastegate actuator settings and a few other things).

 

Well actually after the tune I don't plan on messing with the boost levels because of the crap gas we have here in cali. I was going to get it tuned and just leave it there...so as far as it being adjustable quickly is not really a factor in my particular case....

Also wondering about your WGA for the IX...will it provide any benefit on the stock turbo?? I am getting some crazy taper right now and am trying to remedy it.

 

The actuators (completely depending on proper adjustment and boost control) have been shown to provide some benefits like quicker onset (spool), less taper, smoother transitions, etc.

Again, it's all based on proper adjustment and tuning, but the results are there when setup properly.

 

I don´t know why so many IX turbo guys are complaining of huge boost taper. Look, if you wanna control boost positively and retain the stock boost control solenoid setup with its, for me at least, Byzantine system of restrictor orifices, then you should seek advice from someone that understands tuning an Evo with the stock boost control system in place.

Since you are in the Bay Area you might want to PM a tuner who goes by the nickname of Razorlab(his EvoM callname) in Alameda, CA. I´ve read this guy´s posts and he seems to have a comprehensive approach to setting up boost properly using a slightly modded stock system. The nice thing is that it´s not noticeable to the scrutiny of the CHP( I apologize publicly to Razorlab for bringing him this unsolicited publicity! ).

Like I said, I am amazed by the number of people who complain of huge taper with the IX turbo on the Mivec cars. I had my TME setup so that it would peak and hold 24PSI all day, flatline from 3200 up to 7500 RPM. This was with an MBC, Forge WGA, and a ported hotside, 3¨DP, catless. Are you running a catalytic convertor? What O2 hsg. are you running? Have you checked to see what your base WG pressure is?

 

If you had an MBC, and the Unos is an excellent one, although if cost is a factor and you´re not too worried about comparative quality, then the cheap Dejon should serve you well.

At any rate, with a good MBC, properly hooked up, you could verify base WG pressure and, increase WG preload, which should improve spoolup and might mitigate boost taper, given a free flowing exhaust system, from the O2 hsg on out .

 

Actually I am familiar with razorlab..I was on his dyno this past weekend at GST...he is the one that told me I have a boost leak and suggested I use the stock ecu to control the boost...

Cost is of ZERO factor to me actually. Mainly my two concerns are:

-warrantability
-function as far as being consistent

 

Hey Ken,

Actually I mentioned your baseline boost on your stock evo 9 seemed a bit low compared to others and that it was tapering much lower and faster than other stock evo 9's on our dyno.

If you can, do a boost leak check before adding any parts.

I mentioned the ECU-based boost control because you said you want to get rid of the factory taper while keeping the car looking fairly stock, also less detectable by the dealer and Mr. Officer.

MBC's do work fine. The ECU-based boost control powers are in boost control via RPM and a totally closed-loop error correction system, which, when tuned correctly will keep the boost very consistant no matter the weather, incline, decline, etc. If you don't plan on changing your boost alot after a tune I would highly recommend ECU-based boost control.

It's also cheaper.

 

Thanks for your input Bryan!!

Yah I wanted to pick your brain that day, but the g/f was getting impatient LOL....so yeah basically I was just trying to figure out the pros and cons of both..I am definitely going to fix the leak before doing any mods to the car =)

So basically I am going to fix the leak and then do another baseline to make sure everything is ok...for now I am just continually collecting parts in my storage room. =D

 

Another thing to look at is this. If you let the ECU control the boost, if for some reason your running lean or there is some sort of problem, the computer can control the wastegate to reduce boost. Now if you got a MBC the only way to stop boost is when your turbo reaches the "PSI set point" that you dialed in. There is no other way, so if a problem develops your screwed as far as controlling boost is concerned.

 

This post is in no way meant to demean any product of any company.

However, Mitsubishi spent at some point (probably in the far distant past now) a great deal of money to perfect and seamlessly integrate the factory control system into the rest of the ECU operation. You can make a nearly impossible to detect boost control system out of an already good factory base. Removing the upper restrictor pill will allow a very hefty spike (if desired) for a nice torquey punch and allow as much boost as the stock turbo can muster with the factory actuator at redline.

Other variables aside (and in no way encouraging similar behavior) I can and have run 25psi at peak torque tapering down to about 21-22 at redline with the factory system by itself with only tuning the BCS maps and removing the restrictor pill. If you intend to set it once and leave it alone, run 91 octane fuel everyday, and remain stealth it seems like the best option...at least to me. I am sure Mike@Forge probably would have mixed reviews. Running their actuator and the stock BCS might be an even more "matched to your goal" type strategy.

JB

 

I actually already purchased a Forge WGA for the IX!!

 

Quote:

Originally Posted by JDMevoBOOST

.........need to fix a boost leak at the moment my car peaks at 16.5 and drops to like 12 psi in 85 degree weather.

Is your boost dropping down to 12# because of the boost leak? You should, first of all, fix the leak.

The Forge WGA for the IX should allow you to enhance the spoolup characteristics on your turbo, by dialing in WG preload. Since you went ahead and already bought the improved WGA, it would seem to me at least, that you should take the final step and acquire the Forge UNOS MBC as well.

Together these two products will allow you to dramatically decrease spoolup time and you'll have a rock steady max boost control too. It would seem to defeat the purpose of the improved WGA purchase, to be dinking around with restrictor orifices. At any rate, once you go and install that shiny, new actuator, then your engine bay won't look stealthy anymore, so you might as well go ahead and get the UNOS MBC as well, IMHO.

 

If someone wants to use the stock solenoid, I have nothing against that if it meets their needs. Personally, however, I would not use it myself.

The argument made for the ECU offering more control by possible lowering boost by opening the wastegate sooner is quite misleading, however.

This is only possible after the car is already generating enough boost pressure to open the actuator based on the base spring pressure of the given actuator being used.

The base spring pressure of the given actuator being used determines the lowest level of boost the car can make. Period.

The solenoid does not have the ability to arbitrarily create boost pressure to open the actuator to suit it's needs. It relys on the turbo to generate enough boost pressure that will open the actuator, and then the ECU can decide when it wants to actuate the solenoid to send a pressure signal to the actuator. If the base spring pressure of the actuator being used is 15 PSI (for the sake of this example), the solenoid cannot open the actuator to stop the increase of boost pressure until the turbo is already making the 15 PSI matching the actuator pressure. If the base actuator pressure is set at 20, the car will make a minimum of 20 PSI. etc. etc.

It can't lower you down to 10 nor to any other threshold lower than the base actuator pressure. It's just not possible.