manipulating spool up <boost FEEDBACK>
Originally Posted by Suzuka_Joe' timestamp='1373849808' post='22665676
[quote name='siadam' timestamp='1373752228' post='22664353']
So under the Adv Boost tab in the AEM v2, you just adjust the Boost Error Duty table, to reflect what is show in this thread, do you have to turn on the boost feedback under the options box?
It says boost switch input:switch is always off, then has a boost switch target, and a fuel cut load.
So under the Adv Boost tab in the AEM v2, you just adjust the Boost Error Duty table, to reflect what is show in this thread, do you have to turn on the boost feedback under the options box?
It says boost switch input:switch is always off, then has a boost switch target, and a fuel cut load.
I'd like to know as well. s2knoob89 where you at?
[/quote]
Good info, can you elaborate on this?
BE WARNED I'M TERRIBLE AT TRYING TO EXPLAIN THINGS
With the boost error duty set so high to manipulate boost spool up it doesn't react fast enough in case you have an over boost condition. For example I set mine up when it was around 85-95 F and this morning it was 65ish. I hit in 4th gear and it overshot the boost target and hit boost cut. After it hit boost cut the boost error duty caught up and corrected for the over boost condition. This happened on every gear shift.
With the boost error duty set so high to manipulate boost spool up it doesn't react fast enough in case you have an over boost condition. For example I set mine up when it was around 85-95 F and this morning it was 65ish. I hit in 4th gear and it overshot the boost target and hit boost cut. After it hit boost cut the boost error duty caught up and corrected for the over boost condition. This happened on every gear shift.
BE WARNED I'M TERRIBLE AT TRYING TO EXPLAIN THINGS
With the boost error duty set so high to manipulate boost spool up it doesn't react fast enough in case you have an over boost condition. For example I set mine up when it was around 85-95 F and this morning it was 65ish. I hit in 4th gear and it overshot the boost target and hit boost cut. After it hit boost cut the boost error duty caught up and corrected for the over boost condition. This happened on every gear shift.
With the boost error duty set so high to manipulate boost spool up it doesn't react fast enough in case you have an over boost condition. For example I set mine up when it was around 85-95 F and this morning it was 65ish. I hit in 4th gear and it overshot the boost target and hit boost cut. After it hit boost cut the boost error duty caught up and corrected for the over boost condition. This happened on every gear shift.
you are hitting cut cause your boost error duty table is to aggressive. look at page one of this thread and see the three variants that wadzi posted. either make the side left of the y axis less aggressive or make the side right of the y axis more aggressive and you can fix that issue. you should not have to tweak this in different weather conditions, set it up make it work, then be done with it.
as for the other tables and how they intertwine with each other, wadzi had a great explanation typed up somewhere of how to do this stuff. first, you have to set up the boost table. hopefully i dont butcher this.
so the wg base duty table. he had me set every part of this in boost at 50 to start. 0 means the mac solenoid does nothing and 100 means full blast raise boost as high as possible. he had me set it at 50.
i use boost target method of speed to regulate boost. so on table boost speed target you set what boost you want to see at what speed. this comes into play later. i wanted 14 psi so i said hit 14 at all speeds to get stuff dialed in. then there is the bost target graph. this one is goofy. it looks like a U that got distracted on teh last part of the U and went rogue to the right. so at -14.59 it is at -40 and this stays flat to +7.18 psi, then goes up to my boost target of 14 and that is at 0%. so basically, this talbe should be at 0% at the max boost you want to run. then it tails off to the right and i dont remember why. rogue i guess lol. so when this table is at -40, but the wg duty table is at +50, you are effectively asking the mac solendoid for +10 of work. these two graphs relate to each other. the first graph, the wg duty base duty table, is the one that you will know screw with so that when you want 14 psi, floor it you hit 14psi. if you are overboosting wiht the base settings, then lower the numbers in the wg base duty table. once you find the correct number in that table that equals X psi, ie what you are trying to hit and it maintains it through the pull. now you can screw with spool.
the boost error duty table is the one that wadzi posted. closer to 0% left of the y axis means slower spool. as you get closer to the y axis you want to taper off to 0. this is a modifier of sorts to the wg base duty %. so you are at 0 psi. this table says 0psi is 14 psi off the target, so add 40% to the wg. then the wg base duty table says hey this rpm this load run this % but add that modifier to it. then the boost target comp table says hey this boost reduce it this %. now when you hit your target it says ok stop adding, just run the base %. but if you over shoot your target, the boost error table says hey asshole remove x% from the base wg duty table so that we can fix this. obviously, none of this matters if your running the same boost your wastegate spring runs. FYI lol.
and there you have it. they all work with each other and create boost babies.
i am sure i butchered some of this explanation, but hope it helps others see the matrix and have fun.
Haha I had no clue it was that complicated. I was just using the boost error duty table and boost by speed. Do you mind posting up some screen shots of how you have it setup?
Going to get some chocolate chip cookies now
Going to get some chocolate chip cookies now
Just a couple of my tips:
Use proper wastegate spring and PRELOAD PROPERLY. I run 23 psi spring for example, and peak boost on E85 is 33 psi. This allows great spoolup (29 psi @ 3900 RPM).
Also, USE A 3 PORT BOOST CONTROLLER. This will allow you to control boost levels via your EMS etc. Manual boost controllers are junk in comparison. Although on Evos we run "hybrid boost control" where you use a manual boost controller for low end spool and then a 3 port to control boost curve in the mid-range and top end.
Use proper wastegate spring and PRELOAD PROPERLY. I run 23 psi spring for example, and peak boost on E85 is 33 psi. This allows great spoolup (29 psi @ 3900 RPM).
Also, USE A 3 PORT BOOST CONTROLLER. This will allow you to control boost levels via your EMS etc. Manual boost controllers are junk in comparison. Although on Evos we run "hybrid boost control" where you use a manual boost controller for low end spool and then a 3 port to control boost curve in the mid-range and top end.
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