Boost controller tuning
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But when you adjust the boost via the ecu it is altering the way the solenoids work, and if you have the solenoids bypassed then you are controlling the boost solely with the mbc and then tuning the rest of the ecu around that. This is exactly what I said earlier, but I don't understand why you would want to do this when the taper is much better controlled via the ecu because you can adjust the wastegate duty cycle mapping as the rpms go up to compensate for the boost wanting to bleed off prematurely. MBCs CAN'T DO THAT. Plus, MBCs have driveability issues, like hitting full boost at partial throttle which is annoying and makes the car very jerky, and it's hard to tune around unless you plan on running full throttle all the time. Perhaps for a drag car this is not a problem, but for a street/track car this is not the way to go in my opinion.
Last edited by STi2EvoX; Apr 6, 2008 at 05:44 PM. Reason: typo
Regardless whether the boost is controlled electronically with the ECU (which has mechanical solenoid limitations not experienced by mbc's) it has nothing to do with the rest of the timing and fuel maps. The timing and fueling maps have nothing to do with the boost maps, whether controlled by a solenoid or mbc.
I urge you to do some research on the subject to get a better understanding.
I urge you to do some research on the subject to get a better understanding.
Last edited by TTP Engineering; Apr 6, 2008 at 05:47 PM.
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Well, it is not my intention to argue with you and I mean no disrespect by this, but I am very educated on the principles of engine management and find it strange that you would say that the boost settings have nothing to do with the rest of the maps. If you run higher boost, typically timing is pulled back to compensate. If the car is running higher boost and you don't want to pull timing then the fuel injector duty cycle mapping is usually increased if possible to add more fuel to prevent detonation. Everytime something is adjusted in the ecu it is not mandatory, but certainly recommended to adjust the other tables to bring balance to the tune. If you are a tuner than you should know this. Again, I am not an expert nor have I ever claimed to be one, but one of my best friends is a very experienced dyno tuner that has taught me quite a bit over the years and this is one subject that I am quite certain of. Many tuners have different philosophies about tuning and some clash with one another. Everyone has different preferences, and that is clearly prevelant here. Oh, and btw if you want to talk about the limitations of a stock solenoid setup then don't forget about the boost tapering characteristics of the MBCs and the obvious limitations with those. I agree that the stock solenoids can be limiting when running very high levels of boost, but the easy fix for that, and the best option of all of them is to go with an electronic boost control solenoid like the perrin EBCS. These give lots of headroom for adjusting the boost curve and tend to be much better about preventing boost spike than just about anything. I had one of these on my STi and the difference in both spike prevention as well as improved taper were astounding and put any MBC setup to shame. Either way, I'm sure that you have certain ways of doing things, and so do I. Perhaps we can simply agree to disagree on this one.
Last edited by STi2EvoX; Apr 6, 2008 at 06:07 PM.
The point is the Boost Map does NOT comminicate with the timing and fuel maps. It does not care what is being used to control boost, the ECU is unaware nor can the tune be made "better" with a stock solenoid. Its like making a fire with two sticks. There are easier, faster ways to achieve maximum performance.
We have tuned about 75% of the stock turbo records including our own. Most of them are using a MANUAL BOOST CONTROLLER.
They are inexpensive and work perfectly fine.
There are $600-700 electronic boost controllers in the market for guys like you however. GReddy E01 and HKS EVC VI for example. If you think that is cost effective and want to sell yourself into the need to have one, ther are there for the taking.
We have tuned about 75% of the stock turbo records including our own. Most of them are using a MANUAL BOOST CONTROLLER.
They are inexpensive and work perfectly fine.
There are $600-700 electronic boost controllers in the market for guys like you however. GReddy E01 and HKS EVC VI for example. If you think that is cost effective and want to sell yourself into the need to have one, ther are there for the taking.
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I was actually referring to an electronic boost control solenoid, not a combo solenoid/controller like the EVC. The perrin EBCS runs for about 100 dollars, which is very comparable to most MBCs, and when combined with ecu tuning can create response and taper characteristics that are just awesome. Look, I don't want to argue with you and certainly am not trying to be disrespectful so please stop taking it that way. The point of what I have been trying to say in all of this is that the boost taper is usually better controlled via ecu than with an MBC. MBCs are effective for their intended purpose, but are very "no frills" and imprecise in my opinion. They are subject to overboosting and spiking issues that are not as prevelant with an ecu tune/solenoid setup. Plus I can't stand hitting full boost at partial throttle. Anything that does that is not for me. Different strokes for different folks, I suppose. Oh and BTW, your record of a stock turbo EVO 9 is definitely impressive! 575 HP? I know that's with a bottle, but how much of a shot are you guys running?
Last edited by STi2EvoX; Apr 6, 2008 at 06:37 PM. Reason: typo
But when you adjust the boost via the ecu it is altering the way the solenoids work, and if you have the solenoids bypassed then you are controlling the boost solely with the mbc and then tuning the rest of the ecu around that. This is exactly what I said earlier, but I don't understand why you would want to do this when the taper is much better controlled via the ecu because you can adjust the wastegate duty cycle mapping as the rpms go up to compensate for the boost wanting to bleed off prematurely. MBCs CAN'T DO THAT. Plus, MBCs have driveability issues, like hitting full boost at partial throttle which is annoying and makes the car very jerky, and it's hard to tune around unless you plan on running full throttle all the time. Perhaps for a drag car this is not a problem, but for a street/track car this is not the way to go in my opinion.
If you are running higher boost and are getting a code, there will be a ton of EcuTeK dealers that are vendors on here who can fix that for you. A manual boost controller in and of itself does not taper. Small turbos taper. ihiVF39s on STIs taper bigtime.
Put a quality MBC on an Evo VIII with a 3076 upgrade, and it will hit 24psi at full spool and hold it to the rev limiter. Set the 16g at 24psi, and it will not. You're out of the efficiency range of the turbo.
IMO, a lot of tuners don't tune boost in Ecuflash because the factory boost control system, solenoids and all, is a bit wonky. Some people switch to aftermarket solenoids, but the most straight needle repeatable way to do it is with an MBC.
My car is going to be EcuTeK tuned at Dyno4mance next week or whenever they get the software in. I'd prefer to use ECU boost control, but if the Mitsu electronics aren't up to the task and can't make as pretty of a boost curve as my Hallman, you can bet I'll run the MBC.
I don't like running a lot of boost anyway, and prefer to make power through timing. I've always tuned my car in third gear, and with this turbo or an Evo VIII/IX 16G, I set to 21-22psi in third. With a Hallman pro, I'll rarely see more than 23psi in 5th in the middle. Not only that, but there is logging software with EcuTeK, and of course I'll make sure the car is logged in 5th gear on the interstate.
I've used Mitsulogger in the past on CT9A cars to make sure we never see knock in high gears either.
Take everything you know about tuning Subarus and look at it in a different light. Partial throttle drivability issues did not exist on the 4G63 with high EGTs or overboost codes. Even the drive-by-wire 4B11 with an MBC will be fine on a stock ECU if are not going outside of the paramaters it expects to see. Simple solution: Lower the peak boost. If you are running higher boost and are getting a code, there will be a ton of EcuTeK dealers that are vendors on here who can fix that for you.
A manual boost controller in and of itself does not taper. Small turbos taper. ihiVF39s on STIs taper bigtime.
Put a quality MBC on an Evo VIII with a 3076 upgrade, and it will hit 24psi at full spool and hold it to the rev limiter. Set the 16g at 24psi, and it will not. You're out of the efficiency range of the turbo.
IMO, a lot of tuners don't tune boost in Ecuflash because the factory boost control system, solenoids and all, is a bit wonky. Some people switch to aftermarket solenoids, but the most straight needle repeatable way to do it is with an MBC.
My car is going to be EcuTeK tuned at Dyno4mance next week or whenever they get the software in. I'd prefer to use ECU boost control, but if the Mitsu electronics aren't up to the task and can't make as pretty of a boost curve as my Hallman, you can bet I'll run the MBC.
I don't like running a lot of boost anyway, and prefer to make power through timing. I've always tuned my car in third gear, and with this turbo or an Evo VIII/IX 16G, I set to 21-22psi in third. With a Hallman pro, I'll rarely see more than 23psi in 5th in the middle. Not only that, but there is logging software with EcuTeK, and of course I'll make sure the car is logged in 5th gear on the interstate.
I've used Mitsulogger in the past on CT9A cars to make sure we never see knock in high gears either.
If you are running higher boost and are getting a code, there will be a ton of EcuTeK dealers that are vendors on here who can fix that for you. A manual boost controller in and of itself does not taper. Small turbos taper. ihiVF39s on STIs taper bigtime.
Put a quality MBC on an Evo VIII with a 3076 upgrade, and it will hit 24psi at full spool and hold it to the rev limiter. Set the 16g at 24psi, and it will not. You're out of the efficiency range of the turbo.
IMO, a lot of tuners don't tune boost in Ecuflash because the factory boost control system, solenoids and all, is a bit wonky. Some people switch to aftermarket solenoids, but the most straight needle repeatable way to do it is with an MBC.
My car is going to be EcuTeK tuned at Dyno4mance next week or whenever they get the software in. I'd prefer to use ECU boost control, but if the Mitsu electronics aren't up to the task and can't make as pretty of a boost curve as my Hallman, you can bet I'll run the MBC.
I don't like running a lot of boost anyway, and prefer to make power through timing. I've always tuned my car in third gear, and with this turbo or an Evo VIII/IX 16G, I set to 21-22psi in third. With a Hallman pro, I'll rarely see more than 23psi in 5th in the middle. Not only that, but there is logging software with EcuTeK, and of course I'll make sure the car is logged in 5th gear on the interstate.
I've used Mitsulogger in the past on CT9A cars to make sure we never see knock in high gears either.
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^Yes, I know that the reason for boost taper is the turbo and not the MBC, but the point that I was trying to make was that the shortcomings of a small turbos ability to hold boost can be somewhat compensated for by bumping up the wastegate duty cycle mapping at higher rpms. However, even david buschur was commenting on the 4b11 exibiting the same behavior as the STi in that it hits full boost at half throttle and that that was the reason for the EVO X going into limp mode because of too much torque output for the given throttle input. Perhaps e-throttle cars don't like MBCs and cable types don't mind it. Either way, for what it's worth works tuning told me that the twin solenoid setup on the X has been seen on the JDM EVOs of the past and that it's really cool that we finally got it. They said that it has crazy boost control characteristics and can actually create a reverse taper where the boost actually rises with rpms despite the flow capabilities of the turbo. Obviously you wouldn't want to do this for safety reasons because of the fact that it would put the turbo way past it's efficiency range and would get too hot, but it just illustrates the amount of control that you have with that twin solenoid setup. This coupled with the fact that the X's turbo is pretty massive and should flow quite well, I wouldn't be surprised to see safe tunes of 23 psi from peak all the way to redline. We'll see I suppose, but I hate MBCs and refuse to put one on my car. Different strokes for different folks I suppose. Oh and TTP, I have been polite to you in all of our correspondance and don't appreciate you insulting me. I am no newbie, and that comment was uncalled for. I am very competant with engine management principals, and perhaps I am more familiar with Subarus than Mitsubishis, but many of the principals are the same. Insulting people is not a good way to earn customers, and I think that you should keep that in mind.
Last edited by STi2EvoX; Apr 6, 2008 at 07:38 PM. Reason: typo
^Yes, I know that the reason for boost taper is the turbo and not the MBC, but the point that I was trying to make was that the shortcomings of a small turbos ability to hold boost can be somewhat compensated for by bumping up the wastegate duty cycle mapping at higher rpms. However, even david buschur was commenting on the 4b11 exibiting the same behavior as the STi in that it hits full boost at half throttle and that that was the reason for the EVO X going into limp mode because of too much torque output for the given throttle input. Perhaps e-throttle cars don't like MBCs and cable types don't mind it. Either way, for what it's worth works tuning told me that the twin solenoid setup on the X has been seen on the JDM EVOs of the past and that it's really cool that we finally got it. They said that it has crazy boost control characteristics and can actually create a reverse taper where the boost actually rises with rpms despite the flow capabilities of the turbo. Obviously you wouldn't want to do this for safety reasons because of the fact that it would put the turbo way past it's efficiency range and would get too hot, but it just illustrates the amount of control that you have with that twin solenoid setup. This coupled with the fact that the X's turbo is pretty massive and should flow quite well, I wouldn't be surprised to see safe tunes of 23 psi from peak all the way to redline. We'll see I suppose, but I hate MBCs and refuse to put one on my car. Different strokes for different folks I suppose. Oh and TTP, I have been polite to you in all of our correspondance and don't appreciate you insulting me. I am no newbie, and am in fact right about the fact that the MBCs have issues with the X. Maybe it's because it has an E- throttle much like the STi. Who knows, but don't insult me and act like I'm some "newbie" that doesn't know anything. I am very competant with engine management principals, and perhaps I am more familiar with Subarus than Mitsubishis, but many of the principals are the same. Insulting people is not a good way to earn customers.
There's no need to be abrasive toward TTP. He's trying to help you.
One thing that you seem to not be understanding is the physics of the matter. Even if you forced the wastegate, this 156G turbo on our car will not make flat boost from peak to redline. The turbo is too small, and you're beyond the efficiency range, period. In more normal terms, the volume only goes to 10, so turning it up to 12 won't make it any louder.
As far as the issue Buschur had, it was a partial throttle overboost code. I'm pretty sure I know this because I talked to Jarrod about it when I bought my boost controller from him. He told me to keep my controller just under 24psi. The stock ECU program did not want to see that much boost at the load level, hence the trouble code. Solution: Flash (was not possible at that time) or turn the boost down a bit.
Get a stock Evo VIII and set it to 23psi and it will hit of boost cut that will downright scare you.
Another thing that you are talking against taper, but its actually a good thing in a smaller turbo. You can run an arseload of timing up top, but in the middle RPM band where the turbo is most efficient, you can put lots more cylinder pressure in the form of boost. The benefit is midrange torque. Physics so has it that an MBC follows this desired boost curve to near perfection.
Now is it always the best thing? No. Is it a pain if you are running race gas and pump maps and have to use two different settings? Yes. But an MBC can be the pinnacle of stability that you set first and tune everything else from there. With proper logging and testing, its one thing you can trust to not screw up on you.
For the fun of it, though, I want to try EcuTeK boost. I will definitely be posting up the results and let you know how it goes.
Last edited by Noize; Apr 7, 2008 at 07:05 AM. Reason: Misspelled Jarrod like a tardbox, lol
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I'm still more of a fan of adjusting the boost via ecu tuning because the boost level is dependant on throttle position and won't hit full boost at half throttle like the MBCs can on e-throttle cars seemingly. I had this issue with a hallman pro on my sti and took that POS off after about 10 min. David buschur did say that the X, much like my STi did, was hitting full boost during part throttle scenarios, and that that's why the car went into limp mode. It never went into limp mode at full throttle with the same boost curve. Now you could tune around this, but I don't like the lack of refinement and driveability that goes along with that. And I know what you're saying about it not being ideal to lock in higher boost than what the turbo wants to run, as I even mentioned that earlier in one of my posts. I'm just saying that you can prolong the inevitable drop of the boost curve until a later rpm by wastegate duty cycle tuning, safely creating a broader power band. The turbo on the X should be able to support a boost curve of 23 psi peak tapering to about 20 at redline no problem and not be out of it's efficiency range given the fact that it's basically got the same compressor wheel and turbine wheel as the 9 but with a larger hotside that should FLOW ALOT. I was merely trying to express that the stock solenoid setup, especially the twin setup in the X, can provide enough control to create a better, and still efficient taper than a MBC can. Everyone has different preferences, and based on my experiences with the boost being controlled electronically via the reflash with the access port on my STi, I would never even consider an MBC. Keep in mind that MBCs, even if they can create a good boost curve still are much more subject to overboosting and spiking than what the factory solenoids tend to do. From a precision and driveability point of view, ecu tune FTW. Everyone has different preferences, and these are mine.
Last edited by STi2EvoX; Apr 6, 2008 at 10:08 PM. Reason: typo
I'm still more of a fan of adjusting the boost via ecu tuning because the boost level is dependant on throttle position and won't hit full boost at half throttle like the MBCs can on e-throttle cars seemingly. I had this issue with a hallman pro on my sti and took that POS off after about 10 min.
David buschur did say that the X, much like my STi did, was hitting full boost during part throttle scenarios, and that that's why the car went into limp mode.
It never went into limp mode at full throttle with the same boost curve.
Now you could tune around this, but I don't like the lack of refinement and driveability that goes along with that.
Everyone has different preferences, and based on my experiences with the boost being controlled electronically via the reflash with the access port on my STi, I would never even consider an MBC.
Keep in mind that MBCs, even if they can create a good boost curve still are much more subject to overboosting and spiking than what the factory solenoids tend to do. From a precision and driveability point of view, ecu tune FTW. Everyone has different preferences, and these are mine.
FWIW, I'm not disagreeing with your final conclusion, but some of your logic on the way to get there is flawed. I would _love_ to have my car tuned on EcuTeK boost, because then other than this air filter, it could be 100% stock under the hood and invisible. I like the idea of super clean modification, and would prefer Ecu boost tuning if it works better in the X than it did in the VIII and IX.
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Yeah, I see your point in that maybe the EVOs don't have the driveablity issues that the STis did, but I still think that with David Buschur saying that the car hit 19 psi at half throttle, that's still an issue I think. Even if yours isn't turned up as high and your hitting let's say 17 or 18 psi, that's still like 90% of maximum boost under half throttle. To me, this is not good. Did the EVO 8s and 9s have this issue as well, or is this more an issue with e-throttle cars? I don't see why it would matter, but then again I heard that the EVOs of the past didn't have MAP sensors. Is this true? Anyway, I understand what you are saying and I can see both sides to the coin. I have seen MBCs spike more than ecu tuned cars so it can happen to either. Cold weather + turbo equals spiking beyond the specified targets sometimes, and it just goes with the territory I suppose. FWIW, as I mentioned before when I spoke to works tuning they told me how much more control the twin solenoid setup on the X works than either a single OR a MBC bypassing them altogether, and that it would be selling short the capabilities of the EVO X by not utilizing this setup. They said that JDM EVOs of the past have had this twin solenoid setup since the evo 6 or 7, and that we've been shortchanged until now. Their recommendation was to wait until reflash software comes out because the boost control capabilities of the Xs solenoids are badass and are going to be an integral part of extracting the most from the car once tuned. Either way, as I said before everyone has different preferences and these are mine.
Yeah, I see your point in that maybe the EVOs don't have the driveablity issues that the STis did, but I still think that with David Buschur saying that the car hit 19 psi at half throttle, that's still an issue I think. Even if yours isn't turned up as high and your hitting let's say 17 or 18 psi, that's still like 90% of maximum boost under half throttle. To me, this is not good. Did the EVO 8s and 9s have this issue as well, or is this more an issue with e-throttle cars? I don't see why it would matter, but then again I heard that the EVOs of the past didn't have MAP sensors. Is this true? Anyway, I understand what you are saying and I can see both sides to the coin. I have seen MBCs spike more than ecu tuned cars so it can happen to either. Cold weather + turbo equals spiking beyond the specified targets sometimes, and it just goes with the territory I suppose. FWIW, as I mentioned before when I spoke to works tuning they told me how much more control the twin solenoid setup on the X works than either a single OR a MBC bypassing them altogether, and that it would be selling short the capabilities of the EVO X by not utilizing this setup. They said that JDM EVOs of the past have had this twin solenoid setup since the evo 6 or 7, and that we've been shortchanged until now. Their recommendation was to wait until reflash software comes out because the boost control capabilities of the Xs solenoids are badass and are going to be an integral part of extracting the most from the car once tuned. Either way, as I said before everyone has different preferences and these are mine.
To me, the most precise controller of how much boost you want is your right foot.
Regarding preferences, everyone is very different. Cobb has been gigantic in the Subaru world, but never really caught on in Evo world due to their extremely late arrival into the game. Its all perception. I would never even consider putting an AP on my car, because I don't like the interface and all the drama I had to go through on the older Street Tuners just to dyno tune someone. But that's my preference.
An ECU interface like EcuTeK or Ecuflash that will pull all the factory maps directly to manipulate is infinitely better than playing with a middle man communication like the AP. By trying to make the end user interface more simple, they make control more complex, especially with their boost tuning. I have yet to see a Cobb Subaru that hits the desired boost target with the precision of an MBC.
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Does ecutek have the ability to make changes to see how the car reacts without reflashing the ecu each time a change is made? That was at least at one point the benefit of the access port over the ecutek. I think I read somewhere that ecutek changed this and that it's like the access port in that respect now. I have never used the street tuner software, but rather had my dyno tuner use his tuner pro software, which gives more control over the ecu than the street tuner software did. I know many of the principals of proper tuning from what my tuner (who is also a good friend) has taught me, but I've never done my own tuning and am not familiar with the interface designs of the different softwares that are used. Is ecutek's software easier to work with than the cobb? What about brain flash from works? I hear that they actually have been working with reflash technology for the EVO ECU longer than anyone else. Is that true also? I have been flip flopping back and forth between the works brain flash, ecutek, and the access port but can't seem to make a decision. I love the fact that cobb has off the shelf maps, because I hate mail in flashes that aren't even based on dyno tuned cars with similar mods and too many companies do this. I will only go with reflash software that has a pc based interface where maps can be e-mailed from the company, downloaded onto the pc, and then uploaded into the ecu with a cable that plugs into the obd2 port, or in the X's case the CAN port. I have a buddy that mailed in his evo 9 ecu to dynoflash (I think that's who it was) and when he got it back his car was slower than it was before and just ran like crap. CRAPPY TUNE, QUESTIONABLE COMPETANCE OF THE TUNER, AND THE INCONVENIENCE OF HAVING TO MAIL IN YOUR ECU AND NOT BE ABLE TO DRIVE THE CAR FOR A WEEK. NO THANKS! I hope that ecutek now has the ability to receive maps via email and then load it onto some sort of map manager, because cobb definitely set the bar with that one.