Hey razorlab or gunzo, I was playing around with the current version of ECUFlash, been studying and getting ready. I think I have how to tune the fuel maps, and timing and I know the older Evo's don't have MIVEC on both intake and exhaust....so I got kinda confused so can you explain how to tune for MIVEC? Maybe in a PM if this isn't the place....

Also maybe you can explain how easy it is to tune boost in a X....as in the pic below I don't know of a place to up or lower boost and stuff. And the tutorial for tuning an older Evo got me lost when talking about boost and how he was using a MBC too.

 

To up boost, change the Boost Target Engine Load higher. This is the number the ecu attempts to hit. The wastegate duty cycle map is the base duty cycles it will use and the turbo boost error correction is the map that it will use to change the duty cycle when the boost is not where it should be.

 

This is the incorrect way to change boost. Sure, it works, but you are leaning on error correction to control boost and not to act as small corrections like it should be.

Tuning boost in a nut shell:

1. Tune WGDC tables to attain your desired boost curve

2. Tune Boost Target Engine Load + Boost Control Load Offset to match the target load per RPM and Throttle % that your new boost curve is hitting

3. Fine tune Turbo Boost Error Correction table as you see fit

4. Tune Boost Limit if necessary

 

Thanks razor how do you tune those though? The values aren't in PSI correct? I'm lost when it comes to the boost. Haha. You should teach a class at your shop. I'd pay.

 

WGDC is in duty cycle, higher = more boost, lower = less boost

Boost Target Engine Load is in Load
Boost Control Load Offset is in Load

BTEL + BCLO = target load. Example, at 3800 the car is hitting 250 load, set BTEL at 150 and BCLO at 100 = 250

Turbo Boost Error Correction is in WGDC % correction, so if Load Error is under target Load by a certain amount, it will add WGDC % to try and bring it back to Target

Boost Limit is in Load x RPM

 

So when it comes to WGDC is it a guessing game or is there a way to figure out Xpsi = Xwgdc?

And for your example, why not BTEL at 100 and BCLO at 150?

Just to make sure...but Load at 3800 varies by car or what? Like how did you get 250 load at 3800. Data-logging on first run before tune?

 

There's alot of factors that can change the load:

the gear you're in
boost you're running
general load conditions (incline or decline road, mass, aerodynamics)
size of MAF housing
exhaust back pressure
altitude

this list can go on forever

In my car, I hit lower load cells than people with stock Evos. This is because of my larger diameter MAF housing. The MAF thinks that there is less air than the actual amount that is being taken in. The ECU adjusts the load to a lower load cell which will increase timing, lower AFRs, hit different Mivec degrees, etc. (everything shifts to the left).
My car hits about 230 load @3800 3rd gear, stock Evos should hit around 240 or higher. It's really hard to just assume what load you'll be hitting, you really need a logger that can log it.

 

Thank's SiC. I was doing some more reading and realized the logger will really help with that. And I'm assuning you adjust for all the data logging you do...but really you can't account for every load in ever RPM range. So I'm guessing you try to make the map smooth in the ranges you don't data log for...

And still I'm confused on how the boost control is done...especially when it comes to the WGDC. Also when razor says Boost Target Engine Load is in Load and Boost Control Load Offset is in Load how do you adjust/tune in that? And Turbo Boost Error Correction when razor tried explained it went over my head. Maybe you can explain SiC? or maybe someone PM me? LOL. I think I get how to tune everything except MIVEC and boost. Anyone care to help me figure out how adjust those? Hehe. Just getting ready.

 

Lets put it in a layman way since bryan has more time with OEM boost control than me (never believed it worked until the X )

The engine load is close approximation to boost (stock car since load changes when you change intake or piping size) ie 135 = 1.35bar ~19psi ..

If your target boost for TPS above 60% is 1.5bar ~22psi .. set the Boost Target Engine Load to 150 for the rpm you want ..

Increase the WGDC so that you can achieve the target load .. I use 5% for 0.05bar/0.5psi approximation.. ie OE boost = 18psi ..NEW boost = 21psi = 30% WGDC

ALL THIS ARE APPROXIMATION as a guide .. individual cars vary ..

Observe what the car is actually doing ..
If the boost is higher than preset and its cycling .. WGDC is too high ..
If the boost is lower than preset and its cycling .. WGDC is too low ..
cycling should not be more than 2-3psi ..

Stable boost =

On a catback .. I can run 26psi till 7200rpms ..
On stock exhaust I can push around 21 psi
Only thing I don't understand is USDM cars have problem achieving more than 19psi .. .. the cars are now pretty much similiar only the software separate them

 

Sweet. I think I'm getting this. I was playing with some tables and the "Edit Map Definitions" and all my tables shrunk. Haha. How do I get them to enlarge again? The tables are like half the size they use to be and make the maps look more cluttered...if that makes sense.

Anyways...so the WGDC...how do you calculate the 30% for the 21psi? Like say I want to do 26psi, how do I calculate the WGDC? I'm guessing you would use this "equation"to approximate for all the values is WGDC to archive the boost you set in Boost Target Load. So just how do you figure the WGDC value? I guess I'm lost when you go from 5% at 18psi to 30% at 21psi.

 

as a guide .. its 5% increment for 0.5psi increase .. 3 psi increase = 3*0.5psi = 6 increments of 5% = 30%

Very rough guide .. but something to start with .. Like I said Razorlab is more proficient in this than me I could be spouting nonsense in Razorlab's eyes

I leave the WGDEC alone for now as I find it quite good for now .. maybe USDM is slightly different .. oh and BTW .. the WGDC doesn't max out at 100%.. its 127% ..I'm running only 90% to get 21psi .. you probably can get more out from the car

 

Boost Target Engine Load + Boost Control Load Offset = Target load

So lets say, with error correction off and the boost system running 100% off base wastegate duty cycle...

You tune the base WGDC to 23psi peak at 3500 rom. This *could* equate to 245 load, so at 3500 you set BTEL to 145 and BCLO to 100, this equals 245. Or you can set BTEL to 45 and BCLO to 200. It doesn't matter, the *only* thing that matters is taht BTEL + BCLO = 245.

I usually set BCLO to 200 as it makes it easier to add in my head lower numbers in BTEL

 

Good info for those that are not used to tuning ecu boost control.

Easiest way to do it IMO:
1. Turn off all feedback correction in the rom (zero out the turbo dynamics table)
2. Drop duty cycle down to 50% for a safe starting point (lower if you are not using the stock solenoid)
3. Log a full pull in 3rd gear (making sure you don't over boost)
4. Adjust duty cycle and run again, repeat until you get your desired boost
5. View your log from desired boost run
a. look at your higest load and set your BCLO by taking (highest load - 140) = BCLO
note: 140 is an example you want to leave a little wiggle room should use whatever you want your final max BTEL value to be
b. Set your BTEL table by adding a column to your log (BTEL = load - BCLO) and transfering the resulting values to your BDEL table.
6. Turn error correction back on and make any fine tweaks you need.

 

Okay I think I'm getting it now. Now just to get things a little bit clear. Tune the WGDC first till you get the PSI you want correct? After you get the desired PSI, tune the BTEL and BCLO 2nd and 3rd?

I guess I'm now wondering what the BTEL and BCLO do if you are already getting the PSI you want by adjusting just WGDC... I'm guessing when you get the PSI you want that's for a certain gear and load. So when you find that you adjust BTEL and BCLO so that desired boost is in all gears and all engine loads?

 

Look at it this way.

WGDC tunes your boost curve. That's it.

The BTEL and BCLO are there for error correction. That's it. If the load is below or above target then the system adds or subtracts WGDC to get closer to target.

You can run around with straight WGDC curve with no error correction at all but you aren't using the power of the stock control system.