Gear adjustment is really the only reason I have the AVC-R... I'd rather get the ECU controlling it all.

 

Dus10 / jcs - I had done the research of the bcs utilizing my own vehicle, but had not documented anywhere yet. Originally I had 3 sets of mbc's I utilized but all had their own quirks and idiosyncracies. After some posts about folks playing with the stock bcs did I decide to try it myself. My first experimentation with it was on the dyno yielding very positive results. Of course these runs were done in 3rd gear only, which my tuner and I thought was sufficient, since we mapped out the 3 maps identical. On the street though I noticed a peculiar phenomenon where higher gears would plateau in boost (stayed at 22psi where it should peak to 25 instead). That is when I recollected a post from another evom member about observing gear depenencies in boost and tried tweaking with the other maps. More dyno runs logging boost confirmed this and showed the cold start override in boost rejecting the accepted notion of cold, normal, and dtc mode for the maps.

I've started documenting my findings and hope to post it within the near future as time permits.

Note: the boost plateau I desribed above seems to be more prevalent in higher boost cars. I did not notice it as much on stock or mildly boosted cars.

 

Well today I went out and did some experimentation runs. Wanting to see if the Boost Desired Engine Load settings were in fact gear dependent. Or if the Wastegate Duty Cycle settings were gear dependent.

So I left the Wastegate Duty Cycles alone and maxed out the #1 and #2 changing only the 3rd Boost Desired Engine Load setting to a ridiculously low number so as to lower the target load in order to attempt to see if the car would curb the boost in 5th & 6th gear.

IT did not. There was zero difference in any gear. Car was still boosting into the 24 psi territory.

Next I maxed out all of the Boost Desired Engine load settings to 159.4 and set Wastegate Ducty Cycles #1 & #2 to 100% and set #3 at 30%; once again trying to see if wastegate duty was gear dependent and also trying to see if it is wastegate duty alone that controls the amount of boost.

There was zero difference; in 5th and 6th gear the car behaved exactly like it has been, no drop in psi at all.

So this time I set #3 wastegate duty settings to %100 and set #2 to 30%; I was half expecting a change cause my original thought was that this was the map the car would read from in normal opertaing conditions. Well the results were the same, no change in any gear; and the same went for map #1.

So my last run I was wanting to see a change but I needed to get home, so I couldn't continue with my course of action which would have been to set wastegate duty in map #3 to 30% and and set Boost Desired Engine load in Map #3 to 30 for all settings, and set the the 1 & 2's maps to full max, in hopes of seeing boost cut in 5th and 6th gears only.

Instead I set the Boost desired engine loads to a taper down to 5500rpm and then taper back up to 7000rpm , set boost error correction to an obvious -50% in the bottom cells so as to see a change for sure on overload situation, max wastegate duty @ 50 from 3000 to 5500 rpm and then 110 @ 6000, 120 @ 6500, and 127.5 at 7000.

next run... Boost now maxing out 19-20 psi in 5 gears and will max out at 21psi in 6th if under higher load.

so these settings are definitely dependent on each other, but I need to do one more experiment to see if there is any truth to the gear dependent map theory. Then I'll now for sure...

 

[QUOTE=Dus10]Well today I went out and did some experiment....QUOTE]

how did you set your original desired engine load, load offset, and turbo error correction? if you did this incorrectly you would see no difference.....furthermore, if you want to see how the duty cycle sets the boost, its easy: zero out all turbo error correction control and put ANY value you want for desired engine load....setting these values properly is how you can tell map differences.

p.s. here is my the post where i will discuss the maps and how to cailbrate and tune the bcs system: http://www.norcalevo.net/index.php?o...&topic=14391.0 . it's a work in progress due to time constraints.

 

From the disassembly it would take me some time to work out the conditions, and also I have seven WG maps which doesn't help!

An interesting test would be to perhaps have zero error correction, maxxed out engine load for all tables, and then three different max duty cycles for the three tables, then log the load or boost in each gear.

Another option if using another method of boost control is to use a voltmeter to record the voltage at the solenoid connector in different gears. You would expect the PWM pulse train to give an effective DC voltage (with the slow sample rate of a voltmeter) that is in proportion to the duty cycle.

Another method would be to get logging the duty cycle(s).

 

So today I set Boost Control Load Offset to 90; set # 1 & #2 Boost Desired Engine Load settings to 159.4 for all cells. Set Boost error correction to zero for all cells, and then set map #3 of the Boost Desired Engine Load to 50 for all cells and set the #3 Wastegate Duty map to 40 for all cells.

In theory, if the 3 maps are gear dependent, I should have had more than stock boost in gears 1-4 and very little boost in 5th & 6th.

guess what, 5th & 6th were max boosting just like 1-4 .

So I don't think the 3 maps are gear dependent.

 

Thanks. We need to look into this more then.

 

Dus10 - I am a bit loss for what u r doing. By zeroing out the turbo error correction control u are bascially rendering boost desired contol inoperative. Therefore the only thing it looks upis the wastegate duty maps - which you had all the same thus they would boost the same thru all the gears.

I think you are a bit confused on the operation of the bcs and maps. Boost desire engine load sets the base level so turbo error correction can work. But in order to set bdel is a function of the max wastegate duty because as jcs noted previously before, the stock ecu doesn't understand boost only load.

Now the easiest way to validate it is the following: zero out boost error correction, set max wastgate map w
1 and or 2 high, and map 3 ridiculously low. You will note gears 1-4 boost will be conisitent but flatline in gear 5/6.

 

That's what I said I did in my post above...
I had boost error zero'd out.
I had Map # 3 of the Wastegate Duty Cycle set to 40 for all cells, Maps 1 & 2 I had set to 100 for all cells. There was no difference...

 

Interesting...I have not had the chance to test any Evo VIIIs or MR's, only my IX RS and regular GSRs...these settings work accordingly on them.

 

Can you guys try this out? I'm guessing at the parameters.... I'm guessing the Boost Desired Eng. Load (BDEL) tells the ecu where it wants the engine to operate. So on the BDEL's, it's basically saying it wants the engine to hit 159.4 load and then lower in the upper rpm range. I'm also going to guess that engine load is roughly proportional to torque output.

I'm guessing the wastegate duty controls the boost response, or how quickly it can change the boost so that it can get the engine to the desired load. Boost Limit is how high of an engine load before it cuts boost. No clue about Boost Control Load Offset.

So..... leave all the maps stock except for the BDEL maps. Try going LOWER, like 120 to see if that lowers the boost which I'm guessing it will. Try it in each of the 3 maps and you might see if they're gear dependent.

For the boost limit, I wonder if it'll let you set it below the BDEL. If so, maybe set it lower and I would guess it will hit boost cut; maybe cahnge the Boost Cut Delay Timer down to 0 so it'll hit immediately.

Well, just a thought....

 

Too make this a little easier! Is there a book for this software? Something that shows what each function does. Or am i wishful thinking?

 

I have also done pretty much the same tests as Dus10; from what I have seen it would appear that the maps are not gear based.

 

Already tried that as posted in one of the above posts. Lowered the numbers to 30 for all cells in the BDEL, tried it in each map individually and there was no gear dependency.

This we know for sure; the amount of boost is set by Wastegate Duty Cycle. The 3 maps are not gear dependent as far as I can tell. There is some other logic to them. It seems to me that the Wastegate Duty sets the maximum boost you desire for said RPM range. So if your target load is met at said rpm range then it allows the wastegate duty to go to whatever it's number is. If the actual load is over or under the target you've set then the ECU reads off the Error Correction map and adds or subtracts wastegate duty accordingly. I wish the maps were gear dependent, that would be awesome, but I've found that they're not.

 

Ah, I see it now. I missed it when I skimmed over it this morning, can't be late to work! I'll hopefully be doing a couple experiments my self in a few weeks. Hopefully, we can all figure out what the heck the settings do.