VE Tuning
01-02-2005, 10:04 PM
#1
Registered User
Thread Starter
Join Date: Nov 2004
Posts: 62
Likes: 0
Received 0 Likes
on
0 Posts
VE Tuning
Researching a good turbo set up has lead me to ultimately the best choice for engine management, greddy e-manage is good but can't hold to the injectors that I'll be using and no ignition? became a problem. Bet you guessed it already, AEM EMS, coupled with wideband, iat sensor, and a new map sensor and I'll be ready to go, I hope.
I first learned about tuning in depth itself through many online resources, then a couple weeks ago I ran across How to tune and modify engine management systems by Jeff Hartman. Somewhat in depth speaking in generalities about stand alones, but did not go into depth on the many different ems systems specifically. But had very good info on how ems works, the sensors involved, and basic tuning.
At first I didn't know about ve tuning or volumetric tuning, and almost 2 precious pages were filled up with info on it, not knowing prior knowledge I was disappointed and stuck with it because I threw the recipt at a girlfriend at work after buying the book, so yea that recipt was gone, but being stuck with it I read more and more and sure enough I got hooked, I read this book morning noon and night.
The term ve is a percentage, because we are humans and not perfect ve is below 100%. VE though is basically how much air the engine is receiving, limited throughtout the rev/load points by how much air it can recieve (idle=low ve, cruise=middle of the road ve, wot=highest ve). Just imagine one cylinder representing all 4 cylinders, combine that with how much air can be fed and you got your VE.
VE is simple, just a clean way to tune. VE tuning is easy because the ve will tell the stand alone ecu how much displacement will fill the cylinders at each and every possible combination of rpm and map/load.
The VE fad has been around for a while, even in the aem ems community many people use it, it is effecient, fast, as well as effective. Bad part about this all, not really, is aem ems doesn't just use ve tables. Thanks for whoever found out how, but using the boost compensation fuel trim you can make a psuedo ve table.
The aem ems process of ve tuning: (please correct me if I am wrong I am still somewhat unsure about boost comp ems, just the gist)
1. First off as with all stand alones *make sure your engine can handle it*
-motor in good mech. condition
-no leaks
-go as far as getting an oil analysis to gauge how good of a condition your motor is
-aem working as with all sensors
-check plugs and timing belt if timing belt is off but aem says otherwise calibrate it to the timing belt
2. Compose boost compensation
-0kPa @ -100%boost comp, exponential line to 100kPa @ 0, leading to 200 @ 100
*make sure that ^ matches to the map sensor ex: 1 bar,2 bar, etc...
graph:
http://www.we-todd-did-racing.com/wetoddim...zMXk1NDE%3D.jpg
table:
http://www.we-todd-did-racing.com/wetoddim...zMXk1NDE%3D.jpg
3. Starting with a conservative/rich afr using wot load for each rpm point(table provides light on this), input this into fuel map, used base map of S2000 (not to scale naturally aspirated, used as an example) This is where street tuning takes place or dyno. On an open road or dyno, from atleast 3000 revs put car into wot load and log or real time tune to get a flat fuel afr. Street tuning will put stress on the engine watch coolant temp, etc... Your most likely going to have to use both feet ie brake while getting on the throttle. It would be good to have a co-passenger, to either drive or tune.
fuel map graph:
http://www.we-todd-did-racing.com/wetoddim...zMXk1NDE%3D.jpg
table:
http://www.we-todd-did-racing.com/wetoddim...zMXk1NDE%3D.jpg
4. Then comes throttle mod fuel trim tuning, which is basically deals with part throttle and cruising. Open up the throttle mod, from 0 throttle @ -25% stright line forming a smooth s shape ending up at 50% throttle @ 0% (resolution not small enough in pics leading to a 56% instead of 50). From a little over from where you started the wot runs ie 2500 go from 3000, adjust the throttle mod to get stoich or leaner if you want fuel economy (14.68 afr).
fuel trim graph:
http://www.we-todd-did-racing.com/wetoddim...zMXk1NDE%3D.jpg
fuel trim table:
http://www.we-todd-did-racing.com/wetoddim...zMXk1NDE%3D.jpg
5. Last but not least on the most common aem ve tuning is idle and idle to cruise, adjustments to accel and cranking fuel. After wot run and throttle mod tuning, go to a parking lot or the like then adjust idle *do not use throttle mod to adjust idle* adjust from 500-1000 rev points.
*note*
"-0kPa @ -100%boost comp" in all of those examples I've used x then y, go to picture and from left is x @ right y, ex: (x)value @(y)value
Pictures for reference only not to scale, maps are from start up configs of a na s2000, I believe them to be conservative hopefully but from those values keep an eye out on input from sensors.
A good quote to understanding the center of all of this (ve) used in the context of turbo, aem ems: fuel at 1 bar is twice as much at 2 bar.
Prototype of things to come:
http://www.we-todd-did-racing.com/wetoddim...zMXk1NDE%3D.jpg
-used by many none in the fashion I have in mind hopefully everything will come together or rather be available
For further explanation aim me: lwpsf or like I did time consuming yet after soaking it all its worth it aem forums key words: boost comp, boost compensation, flat fuel
I first learned about tuning in depth itself through many online resources, then a couple weeks ago I ran across How to tune and modify engine management systems by Jeff Hartman. Somewhat in depth speaking in generalities about stand alones, but did not go into depth on the many different ems systems specifically. But had very good info on how ems works, the sensors involved, and basic tuning.
At first I didn't know about ve tuning or volumetric tuning, and almost 2 precious pages were filled up with info on it, not knowing prior knowledge I was disappointed and stuck with it because I threw the recipt at a girlfriend at work after buying the book, so yea that recipt was gone, but being stuck with it I read more and more and sure enough I got hooked, I read this book morning noon and night.
The term ve is a percentage, because we are humans and not perfect ve is below 100%. VE though is basically how much air the engine is receiving, limited throughtout the rev/load points by how much air it can recieve (idle=low ve, cruise=middle of the road ve, wot=highest ve). Just imagine one cylinder representing all 4 cylinders, combine that with how much air can be fed and you got your VE.
VE is simple, just a clean way to tune. VE tuning is easy because the ve will tell the stand alone ecu how much displacement will fill the cylinders at each and every possible combination of rpm and map/load.
The VE fad has been around for a while, even in the aem ems community many people use it, it is effecient, fast, as well as effective. Bad part about this all, not really, is aem ems doesn't just use ve tables. Thanks for whoever found out how, but using the boost compensation fuel trim you can make a psuedo ve table.
The aem ems process of ve tuning: (please correct me if I am wrong I am still somewhat unsure about boost comp ems, just the gist)
1. First off as with all stand alones *make sure your engine can handle it*
-motor in good mech. condition
-no leaks
-go as far as getting an oil analysis to gauge how good of a condition your motor is
-aem working as with all sensors
-check plugs and timing belt if timing belt is off but aem says otherwise calibrate it to the timing belt
2. Compose boost compensation
-0kPa @ -100%boost comp, exponential line to 100kPa @ 0, leading to 200 @ 100
*make sure that ^ matches to the map sensor ex: 1 bar,2 bar, etc...
graph:
http://www.we-todd-did-racing.com/wetoddim...zMXk1NDE%3D.jpg
table:
http://www.we-todd-did-racing.com/wetoddim...zMXk1NDE%3D.jpg
3. Starting with a conservative/rich afr using wot load for each rpm point(table provides light on this), input this into fuel map, used base map of S2000 (not to scale naturally aspirated, used as an example) This is where street tuning takes place or dyno. On an open road or dyno, from atleast 3000 revs put car into wot load and log or real time tune to get a flat fuel afr. Street tuning will put stress on the engine watch coolant temp, etc... Your most likely going to have to use both feet ie brake while getting on the throttle. It would be good to have a co-passenger, to either drive or tune.
fuel map graph:
http://www.we-todd-did-racing.com/wetoddim...zMXk1NDE%3D.jpg
table:
http://www.we-todd-did-racing.com/wetoddim...zMXk1NDE%3D.jpg
4. Then comes throttle mod fuel trim tuning, which is basically deals with part throttle and cruising. Open up the throttle mod, from 0 throttle @ -25% stright line forming a smooth s shape ending up at 50% throttle @ 0% (resolution not small enough in pics leading to a 56% instead of 50). From a little over from where you started the wot runs ie 2500 go from 3000, adjust the throttle mod to get stoich or leaner if you want fuel economy (14.68 afr).
fuel trim graph:
http://www.we-todd-did-racing.com/wetoddim...zMXk1NDE%3D.jpg
fuel trim table:
http://www.we-todd-did-racing.com/wetoddim...zMXk1NDE%3D.jpg
5. Last but not least on the most common aem ve tuning is idle and idle to cruise, adjustments to accel and cranking fuel. After wot run and throttle mod tuning, go to a parking lot or the like then adjust idle *do not use throttle mod to adjust idle* adjust from 500-1000 rev points.
*note*
"-0kPa @ -100%boost comp" in all of those examples I've used x then y, go to picture and from left is x @ right y, ex: (x)value @(y)value
Pictures for reference only not to scale, maps are from start up configs of a na s2000, I believe them to be conservative hopefully but from those values keep an eye out on input from sensors.
A good quote to understanding the center of all of this (ve) used in the context of turbo, aem ems: fuel at 1 bar is twice as much at 2 bar.
Prototype of things to come:
http://www.we-todd-did-racing.com/wetoddim...zMXk1NDE%3D.jpg
-used by many none in the fashion I have in mind hopefully everything will come together or rather be available
For further explanation aim me: lwpsf or like I did time consuming yet after soaking it all its worth it aem forums key words: boost comp, boost compensation, flat fuel
01-03-2005, 06:39 AM
#2
Registered User
Join Date: Sep 2004
Posts: 112
Likes: 0
Received 0 Likes
on
0 Posts
welcome to the wonderful world of EFI tuning.
You should also check out Ben Strader's book, 'Building and Tuning High Performance EFI'
http://www.amazon.com/exec/obidos/tg/detai...ce&s=books&st=*
And if you get a chance to get into one of these class, they shed a whole new light on tuning EFI: http://www.efi101.com/about.html
You should also check out Ben Strader's book, 'Building and Tuning High Performance EFI'
http://www.amazon.com/exec/obidos/tg/detai...ce&s=books&st=*
And if you get a chance to get into one of these class, they shed a whole new light on tuning EFI: http://www.efi101.com/about.html
01-03-2005, 12:11 PM
#3
Registered User
Thread Starter
Join Date: Nov 2004
Posts: 62
Likes: 0
Received 0 Likes
on
0 Posts
I have looked at efi univ. definately worth the money from what people that went have said, I've actually been on their forum a lot of times just looking up stuff on search.
01-12-2005, 10:11 PM
#4
The Autronic computer from Australia uses VE tables and a air/fuel ratio table. Once you have tuned the VE tables to match the target A/R ratios you can change the AF table and the change in mixture pretty well follows the change in values. It has Autotune functions that tunes the VE table values to your target AF ratios. Pretty groovy.
Speedracer.
Speedracer.
Thread
Thread Starter
Forum
Replies
Last Post