emb tuning: ideal method to trim fuel

K

karnaugh2005

Fresh Recruit
Hi,
Just want to ask what would be the ideal method to trim my car fuel using emb. Here is my current setup:

- stock internal
- hks actuator
- apexi avcr
- emb
* ignition and injection harness connected
* stock map
* stock map also connected to emb tps so that i use can air flow map since engine stock tps is only on/off
- custom exmanifold
- fmic
- ct9a
- relocated air filter
- innovate lc1 afr gauge

I set the boost to .82kg/cm2(11.7psi) and on wot afr is 10.2. I'm thinking the following approach to trim the fuel.

1) air flow map --> pull fuel on wot, but i think this map would have effect on the timing
2) ignition map --> by retarding timing for couple of degree.


Hope someone can shed some light and point me to the correct direction.

thanks
 
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A

AdamB

Member +
10.2 AFR @ WOT is very rich for the boost you are running.
The emanage blue should be able to trim fuel from the map, the ignition map won't trim fuel by retarding the timing, you'll just end up with a lot of unburnt fuel out the exhaust and very little power.

Did you tune it yourself on the emanage? I would be aiming for around 11.8 AFR with that sort of boost level.
 
Texx

Texx

Super Moderator
AFAIK you can't trim fuel with the EMB without the trade off of altering the ignition timing.

The stock ECU tends to fuel a little on the rich side when running more than 0.7bar boost, so preventing it from reading that increase in boost pressure via the PIM voltage from the MAP sensor could solve your problem.

Try clamping the PIM voltage just below 4v (which should equate to approx 10psig boost pressure), then add any additional fuel required to run above the 10psig by using the 'Additional Injection Map'. You'd also need to check for any engine knock using a pair of det cans or something similar and make alterations to the ignition timing accordingly.
 
K

karnaugh2005

Fresh Recruit
thanks for the quick reply adam and texx.

@adam -> Yes i'll tune my car myself

@texx -> I got your point and i'll consider it as #1 option now. btw if timing retard is no use for trimming fuel. How about the airflow map and do i still need to clamp the boost limiter to 4v when using this? does the airflow mapping accurate to use? because I used map sensor instead of tps sensor for the emb throttle position.
 
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K

karnaugh2005

Fresh Recruit
also anyone care to share their emb gsc file for 13-14psi boosted, I wouldnt use it in my car, I'll only analyze how everyone mapped their emb.

thanks
 
Chris@CCM

Chris@CCM

Member +
just lower the boost cut setting untill its a lean as u want it keep a eye out for det too as some timing might need pulled
 
R

Rev

Member +
When I look at your dyno I see 131.53 WHP ( 158 BHP ) at about 8.3 psi that sounds fine to me. More torque would be welcome but may not be feasible with hotter temps.
 
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K

karnaugh2005

Fresh Recruit
numbers was good but when i drove it.. nah stock setup was more even better

Rev said:
When I look at your dyno I see 131.53 WHP ( 158 BHP ) at about 8.3 psi that sounds fine to me. More torque would be welcome but may not be feasible with hotter temps.
Click to expand...
 
K

karnaugh2005

Fresh Recruit
noted Rev. but car setup is different now and need to retune it again and this time i want it tune to its full potential for given boost.

Another question guys. If I use the greddy 3bar map do i still need to set the boost cut limiter lower than 4v, even my target boost is still @13psi?
 
ramses974

ramses974

Member +
karnaugh2005 said:
noted Rev. but car setup is different now and need to retune it again and this time i want it tune to its full potential for given boost.

Another question guys. If I use the greddy 3bar map do i still need to set the boost cut limiter lower than 4v, even my target boost is still @13psi?
Click to expand...

yes boost cut a 4.15v exactly .
 
K

karnaugh2005

Fresh Recruit
I'm changing the table scale but decided to check the map sensor voltage first and I noticed the max voltage that i can only read is ~4.5v and not 5v. I used air compressor with regulator and avcr for reading. And here what i got:

PSI --> Voltage reading
-5 (inhg) --> 2v
0 --> 2.6v
1.9 --> 2.79v
2.9 --> 3v
3.9 --> 3.09v
4.9 --> 3.22v
5.9 --> 3.35v
6.9 --> 3.49v
7.9 --> 3.62v
8.9 --> 3.74v
9.8 --> 3.84v
10.8 --> 3.98v
11.8 --> 4.11v
12.7 --> 4.24v
13.7 --> 4.35v
14.2 --> 4.45v

I searched and found the 2bar map expected normal voltage is from 0.5 to 4.5v. So does this means it would be better if i scaled it just like the data i got and not from 2v to 5v?


Also do you think below initial mapping is a good starting point?

injection.jpg

ignition.jpg
 
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S

SebiZaah

Fresh Recruit
The E-Manage blue can do MANY things !!

It comes down to how clever you wanna be with it.

Also, It is possible to lean fuel on EMB without altering ignition timing.. What I do is take fuel from the entire map to begin with until there isn't any too rich spots in my rev / boost range.
I pull out fuel by imputting a higher injector correction value than you are actually using. For exmaple, I use standard injectors 295cc rate... But My EMB is set to 320cc so it run leaner throughout the entire ECU program.

I then add Fuel using additional injection map and GReddy MAP sensor (can use standard map sensor no difference of outcome)..
And add / remove timing as needed using timing map on EMB and GReddy MAP sensor again.

My engine is reasonably standard.. exhaust thats it. I have only needed to add timing and mostly lean fuel to gain a nice power and drivablility with EMB. :D
 
ramses974

ramses974

Member +
karnaugh2005 said:
need your help guys i'm going to try this on weekend.
Click to expand...

as Texx said, you need to hear the detonation...You cannot put any (-) timing by only thinking it will be at each rpm for each boost...
Adjusting the timing depends from a lot of factor (fuel ron, temp,turbo ,etc ) and you cannot think it will be there (-) or (+)...

Why do not you work by pressure ? it is more easy and accurate to tune the emb
 
Chris@CCM

Chris@CCM

Member +
SebiZaah said:
The E-Manage blue can do MANY things !!

It comes down to how clever you wanna be with it.

Also, It is possible to lean fuel on EMB without altering ignition timing.. What I do is take fuel from the entire map to begin with until there isn't any too rich spots in my rev / boost range.
I pull out fuel by imputting a higher injector correction value than you are actually using. For exmaple, I use standard injectors 295cc rate... But My EMB is set to 320cc so it run leaner throughout the entire ECU program.

I then add Fuel using additional injection map and GReddy MAP sensor (can use standard map sensor no difference of outcome)..
And add / remove timing as needed using timing map on EMB and GReddy MAP sensor again.

My engine is reasonably standard.. exhaust thats it. I have only needed to add timing and mostly lean fuel to gain a nice power and drivablility with EMB. :D
Click to expand...

That changes the load the stock ecu is seeing there for changes the timing
 
K

karnaugh2005

Fresh Recruit
you are right bro. I just converted kg/cm2 absolute to kg/cm2 relative sea level and it matches to the target voltage/boost i wanted.

big thanks

ramses974 said:
as Texx said, you need to hear the detonation...You cannot put any (-) timing by only thinking it will be at each rpm for each boost...
Adjusting the timing depends from a lot of factor (fuel ron, temp,turbo ,etc ) and you cannot think it will be there (-) or (+)...

Why do not you work by pressure ? it is more easy and accurate to tune the emb
Click to expand...
 
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