jcsbanks

I've noticed when you stamp on the throttle that the ignition can retard before the airflow or boost level has jumped up.

Agent-Smith

I would assume this is to momentarily heat up the exhaust flow and allow a little bit of fuel out to spool the turbo up.

JohnBradley

iTrader: (30)

Is there any reason to scale out past 319 (boost limit) or if thats set at 319 it means it has been completely disabled? I guess what I am asking is does that refer to load cell or not? I know Al has flashed a car that hit a max of 36psi and then tapered, so I have reason to believe it isnt a load cell, but you never know.

FWIW I scaled my maps to 340 and 8500 rpm, just to see what it looks like. IX's have all that extra to work with. I only deleted load cell 10 and 70(or 50...cant remember right off) and then took at 750 and 11000 on the RPM axis.

MalibuJack

iTrader: (5)

Yeah I dont think the boost cut represents a load value.. Not sure what it does represent, but setting it to the max, and setting the timer as high as you think is necessary all but disables it..

jcsbanks

Only case study I have of the fuel cut is that it worked when I hit 310 KPa absolute it kicked in when the fuel cut was set at 285, but it allowed 290 KPa through. So it might be quite like load on my setup.

4G63

iTrader: (4)

Would changing the load values from even numbers to odd numbers screw anything up? Basically, would it screw anything up if you took load values "30 ,40, 50, 60" and changed them to just "35, 55" to gain the 2 load area's? The ECU could interpolate that data, correct?

Ludikraut

iTrader: (17)

I don't think the ECU cares what numbers you put into the Load scale. Remember, the values that you are seeing displayed are actually converted from the hex numbers in the ECU.

Ultimately, whatever scaling you choose, you just want to make sure that you have have smooth transitions throughout the various cells in your map.

l8r)

hondafan

iTrader: (25)

can anyone comment on my post #30 please? i'm just wondering what some of you guys would do since alot of you seem more experienced at this than me.

Ludikraut

iTrader: (17)

To answer your question, hondafan, yes it is possible to hit the 260 load cells on only 21 psi of boost. Most likely you'll hit them in the 3500-4500 rpm range. It's fairly unlikely that you'd hit them past 5000 rpm on a stock turbo, though. With the 50 trim I've actually hit 280+ at 20-21 psi ...

l8r)

MalibuJack

iTrader: (5)

I have freqently hit the 260 load cell, it depends on a few things, but its basically the ratio of airflow through the sensor vs RPM (technically thats volumetric efficiency but I'm simplifying it) The calibration and smoothing of the sensor influences what load site it goes into.. Figure if you have a stock intake, or a turbo that spools fast and spikes earlier, you can go into the 260 load site or higher. If your turbo moves alot of air at a lower RPM (For example a GT35r) you can jump into 260 or higher even at lower boost. If you have something adjusting your MAF value (aftermarket intake which lowers freqency on some cars) it can delay it.. You have to log your MAF freqency vs RPM to really see, if it comes on earlier than stock, or is very high, then your definitely getting into those cells.

justchil

iTrader: (44)

Great thread. I still need to read the entire thing but I've been thinking about doing this.

Mad_SB

iTrader: (8)

I hit about 280 - 300 if i do a 3rd gear pull from 2,000 rpm. I hit over 300 If I do a 3rd gear pull from around 3,000 or so. Only mods are TBE and about 21psi.

It is not a linear relationship between boost and load. Seems to be rate of change based cause although I hit 280+ it does not stay there for more than 500 rpms or so. If you don't want the ecu to extrapolate values when you fall outside your map limits you need to rescale.

hondafan

iTrader: (25)

OK, because i'm hitting 260 cells(i believe by the timing i'm encountering)at right around 4K doing a 3rd gear pull from around 3K. so i should add a 280 load cell and adjust my map accordingly? i saw in some other post about the 260 cell being around 23 psi which is why i was asking if i could hit that at 21, so i guess that chart is a rough guesstimate? another thread had a formula for load using MAF Hz(load=MAF Hz*852/RPM), would that be closer to my actual load?

Ludikraut

iTrader: (17)

That formula seems to be pretty close for determining load value. It (read: the *852) varies a little bit from car to car, but it will get you very close.

l8r)

justchil

iTrader: (44)

Here is my changes if anyone wants to look. These are MY maps so there shouldn't be a problem posting.. if you don't want these junkin up the thread just let me know!