Sharing ROMs So We Can Learn
Most people share their tuning knowledge in this forum, as far as I can tell. I just don't think anyone has the time to write a complete tuning guide at this time.
I would suggest simply posting specific questions in different threads and I'm sure there will be answers. Tuning isn't rocket science, but you do generally have to know what you're doing.
This is what I would recommend:
1. Get a grasp on fuel trims, how they work, and closed loop operation. This will give you all the information that you need to tune for injectors and the 'drivability' of your car. This will also enable a smooth transition to open loop (WOT tuning). There have been plenty of threads on this topic.
2. Log, log, and then log some more. You can't do anything if you don't log and see what's going on. Try to get a wideband and map sensor that you can also include in your logs. This will help you tune your afr curve better.
3. Always log knock. Basically, you are trying to tune for maximum power with the least amount of knock. At least for WOT tuning. Partial throttle tuning is another ballgame altogether, but most 'tuning' questions revolve around WOT tuning.
4. The three major tuning parameters we have is timing, open-loop fueling and boost. More timing is generally more power (up to MBT), less fuel is generally more power (to about 12.5:1, which is max rich power for gasoline), and more boost is generally more power (depending on the efficiency of your turbo, intercooler, etc). It is up to you to find the magic combination that is right for your car and your modifications.
So, just using this general information, this is what I would do to start 'tuning' for WOT at least.
- Go to a dyno or a nice open road where there is no traffic and you don't risk getting a ticket. Do a pull, maybe a full third gear pull from 2000 RPM to redline. Log the pull. Include wideband, boost, timing, RPM, and knock, at a minimum. You can also log more parameters for calculated load, or just use your timing and RPM numbers to decipher load cells after the fact. Or for the more advanced people, you can log your two-byte load. (You have to search for this one)
- First, look at your knock. Make sure you don't have any large amounts at first? If so, at what RPM. Your ECU should be pulling roughly 1 degree of timing for every 3 knock counts. So, if you have 6 counts of knock at 5000RPM and your timing is 6 degrees, then go look at your high octane timing map in ECUFlash and go look at your 5000 RPM row and look for a timing of 8*. That is the load cell that you are in. Do this for more points to 'trace' your pull through your timing and then fuel maps. This will let you know what load and what cells you are running through. To get rid of knock, you generally have to do one of three things...lower boost, lower timing, or increase fuel. I personally like to decrease timing to get rid of knock. Once you have any major knock out of the way, then you can start altering your fueling, timing, and boost.
- I do fueling first. Look at your AFR curve. This is my opinion, but I like to get my AFR at the richest point that it is going to be right before max boost. For example, if I want 11:1 on pump gas, I am going to tune the fuel cells right at and before the boost maximum to get me to 11:1. Then I continue this 11:1 to redline. Others like to be leaner earlier, like 12:1, but not me. I generally tune to 11:1 or in that range on pump gas right from max boost all the way to redline....a nice flat line.
- Now, since fueling is done, you have two more variables....boost and timing. What you do with this really depends on what turbo and IC you are running. Boost levels largely depend on the compressor efficiency of the turbo, cooling efficiency of your IC and volumetric efficiency of your entire setup. Again, you will have to experiment for yourself, but if you look around, for the stock turbo a lot of people are running in the 20-22 psi range on pump, maybe tapering to about 18 at redline. Set your boost to this level and log again. Is there any knock? If so, use your timing to get rid of it.
- Now, you just have one thing left, timing. Your fuel is at a flat 11:1, your boost is set to 22-18 or whatever. So, now, start increasing your timing a little by little until you see some knock. Now find what cell you are in for that timing and RPM number. You have found the limit of timing that you can run for that AFR and boost level in that load cell. Maybe back off 1-2 degrees. Do this same thing over and over until you have the most timing at every RPM load that you can run without any knock. Always back off a degree or two for a safe, conservative tune. If you are only doing third gear pulls to tune, for example, then if you go drag race, and do 1-4 to redline, then your third gear tune may need to be 'de-tuned' a bit becuase it will knock during the 1-4 pull, especially in 4th. Lowering the timing from your third gear pull is this 'detuning'. Exactly how much depends on exactly what you will be using your car for. Just log, log, log, and you will get used to it and what you have to adjust.
So, there's a 10,000 foot view of how to start some general WOT tuning. Just try to get used to logging and reading your logs. Then you must learn how to trace your logs into your fuel and timing maps. Use RPM and timing numbers to find the load that you cells that you are running in. Then you will know what cells you are in for your timing and fuel maps. One thing I forgot to mention above is 'How do I know that my tuning changes are working or making more power?' Well, that is pretty simple, too. Look at your logs and the time it takes to go from a certain RPM to a certain RPM, say 4500-7500. If that time is decreasing, then your power is increasing. You can also use tools like Data Log Lab to show a dyno comparison from one run to the next.
And also, another good point is that what is good for someone else's car may not necessarily be good for yours. But, you can always 'experiment' safely as long as you monitor knock. Maybe you want to try for 12:1 on pump gas. Well, go ahead, but not with the same timing and boost that you tuned for 11:1 with. Either lower your timing overall or your boost, then tune for 12:1, with no knock. Look at acceleration comparisons (time for RPM to RPM) from your 12:1 tune and your 11:1 tune. Which is better? As you can see by now, there are a million possibilites....it's up to you to find out which works best for your car and your mods.
This is all very general information and just used ceratin numbers for examples. All of these are variables, which you have to tune for yourself and your own car. But, as long as you log knock and minimize or eliminate it, at least you will be safe and don't have to worry about breaking anything. Just take it slow and don't go too crazy all at once. It will take a while to get a full proper tune. When you are done with WOT tuning, then you can concentrate your efforts on part throttle and transitions to WOT.
Eric
I would suggest simply posting specific questions in different threads and I'm sure there will be answers. Tuning isn't rocket science, but you do generally have to know what you're doing.
This is what I would recommend:
1. Get a grasp on fuel trims, how they work, and closed loop operation. This will give you all the information that you need to tune for injectors and the 'drivability' of your car. This will also enable a smooth transition to open loop (WOT tuning). There have been plenty of threads on this topic.
2. Log, log, and then log some more. You can't do anything if you don't log and see what's going on. Try to get a wideband and map sensor that you can also include in your logs. This will help you tune your afr curve better.
3. Always log knock. Basically, you are trying to tune for maximum power with the least amount of knock. At least for WOT tuning. Partial throttle tuning is another ballgame altogether, but most 'tuning' questions revolve around WOT tuning.
4. The three major tuning parameters we have is timing, open-loop fueling and boost. More timing is generally more power (up to MBT), less fuel is generally more power (to about 12.5:1, which is max rich power for gasoline), and more boost is generally more power (depending on the efficiency of your turbo, intercooler, etc). It is up to you to find the magic combination that is right for your car and your modifications.
So, just using this general information, this is what I would do to start 'tuning' for WOT at least.
- Go to a dyno or a nice open road where there is no traffic and you don't risk getting a ticket. Do a pull, maybe a full third gear pull from 2000 RPM to redline. Log the pull. Include wideband, boost, timing, RPM, and knock, at a minimum. You can also log more parameters for calculated load, or just use your timing and RPM numbers to decipher load cells after the fact. Or for the more advanced people, you can log your two-byte load. (You have to search for this one)
- First, look at your knock. Make sure you don't have any large amounts at first? If so, at what RPM. Your ECU should be pulling roughly 1 degree of timing for every 3 knock counts. So, if you have 6 counts of knock at 5000RPM and your timing is 6 degrees, then go look at your high octane timing map in ECUFlash and go look at your 5000 RPM row and look for a timing of 8*. That is the load cell that you are in. Do this for more points to 'trace' your pull through your timing and then fuel maps. This will let you know what load and what cells you are running through. To get rid of knock, you generally have to do one of three things...lower boost, lower timing, or increase fuel. I personally like to decrease timing to get rid of knock. Once you have any major knock out of the way, then you can start altering your fueling, timing, and boost.
- I do fueling first. Look at your AFR curve. This is my opinion, but I like to get my AFR at the richest point that it is going to be right before max boost. For example, if I want 11:1 on pump gas, I am going to tune the fuel cells right at and before the boost maximum to get me to 11:1. Then I continue this 11:1 to redline. Others like to be leaner earlier, like 12:1, but not me. I generally tune to 11:1 or in that range on pump gas right from max boost all the way to redline....a nice flat line.
- Now, since fueling is done, you have two more variables....boost and timing. What you do with this really depends on what turbo and IC you are running. Boost levels largely depend on the compressor efficiency of the turbo, cooling efficiency of your IC and volumetric efficiency of your entire setup. Again, you will have to experiment for yourself, but if you look around, for the stock turbo a lot of people are running in the 20-22 psi range on pump, maybe tapering to about 18 at redline. Set your boost to this level and log again. Is there any knock? If so, use your timing to get rid of it.
- Now, you just have one thing left, timing. Your fuel is at a flat 11:1, your boost is set to 22-18 or whatever. So, now, start increasing your timing a little by little until you see some knock. Now find what cell you are in for that timing and RPM number. You have found the limit of timing that you can run for that AFR and boost level in that load cell. Maybe back off 1-2 degrees. Do this same thing over and over until you have the most timing at every RPM load that you can run without any knock. Always back off a degree or two for a safe, conservative tune. If you are only doing third gear pulls to tune, for example, then if you go drag race, and do 1-4 to redline, then your third gear tune may need to be 'de-tuned' a bit becuase it will knock during the 1-4 pull, especially in 4th. Lowering the timing from your third gear pull is this 'detuning'. Exactly how much depends on exactly what you will be using your car for. Just log, log, log, and you will get used to it and what you have to adjust.
So, there's a 10,000 foot view of how to start some general WOT tuning. Just try to get used to logging and reading your logs. Then you must learn how to trace your logs into your fuel and timing maps. Use RPM and timing numbers to find the load that you cells that you are running in. Then you will know what cells you are in for your timing and fuel maps. One thing I forgot to mention above is 'How do I know that my tuning changes are working or making more power?' Well, that is pretty simple, too. Look at your logs and the time it takes to go from a certain RPM to a certain RPM, say 4500-7500. If that time is decreasing, then your power is increasing. You can also use tools like Data Log Lab to show a dyno comparison from one run to the next.
And also, another good point is that what is good for someone else's car may not necessarily be good for yours. But, you can always 'experiment' safely as long as you monitor knock. Maybe you want to try for 12:1 on pump gas. Well, go ahead, but not with the same timing and boost that you tuned for 11:1 with. Either lower your timing overall or your boost, then tune for 12:1, with no knock. Look at acceleration comparisons (time for RPM to RPM) from your 12:1 tune and your 11:1 tune. Which is better? As you can see by now, there are a million possibilites....it's up to you to find out which works best for your car and your mods.
This is all very general information and just used ceratin numbers for examples. All of these are variables, which you have to tune for yourself and your own car. But, as long as you log knock and minimize or eliminate it, at least you will be safe and don't have to worry about breaking anything. Just take it slow and don't go too crazy all at once. It will take a while to get a full proper tune. When you are done with WOT tuning, then you can concentrate your efforts on part throttle and transitions to WOT.
Eric
Thats a good and concise summary.. Its actually information that is posted all over the place, but its nice to have it all in one location.
There are some things that are best resolved by asking questions, for instance getting the car to idle better, or making adjustments for closed loop, or some cause-effect relationships that aren't quite as obvious (such as how your timing can alter your AFR's slightly, or the relationship of EGT to AFR's and Timing and how that can be used to tune for different types of racing)
The common "Non-power" related tuning questions that get asked are mostly around fuel trims, injector scaling, setting boost control parameters, altering the Idle Stepper tables, initial stepper settings, Idle speed, part throttle tuning an drivability, etc.. All the info is out there, but can be a little hard to find. You don't need a map as an example for these things, in fact, their frequently overlooked, even by professional tuners who frequently don't create a more drivable car, just a car with more power.. So drivability quirks usually are explained away as "The cost of driving a modified car"
There are some things that are best resolved by asking questions, for instance getting the car to idle better, or making adjustments for closed loop, or some cause-effect relationships that aren't quite as obvious (such as how your timing can alter your AFR's slightly, or the relationship of EGT to AFR's and Timing and how that can be used to tune for different types of racing)
The common "Non-power" related tuning questions that get asked are mostly around fuel trims, injector scaling, setting boost control parameters, altering the Idle Stepper tables, initial stepper settings, Idle speed, part throttle tuning an drivability, etc.. All the info is out there, but can be a little hard to find. You don't need a map as an example for these things, in fact, their frequently overlooked, even by professional tuners who frequently don't create a more drivable car, just a car with more power.. So drivability quirks usually are explained away as "The cost of driving a modified car"
Thread Starter
Evolving Member
iTrader: (19)
Joined: Jan 2007
Posts: 400
Likes: 0
From: Lawrence, IN
although this is a good write up on "how to" im a little confused about tuning afrs first?...would you actually turn up the boost to the desired psi and slowly adjust fuel to the target afrs?...or tune for target afrs, but wouldn't the boost pressure increase lean the target afrs? im a noob at tuning and would like the advice from others who would like to learn just like me...i also dont have any tuners in site for another 300miles...
--malibujack i also registered on aktivematrix but did not get the link to activate...i think i ended in my junk mail which i threw away like a dumb *** but i did email you and you asked me what handle did i use?...im not too sure what you meant by that!...help...i would like to start logging
thanks
bobby
--malibujack i also registered on aktivematrix but did not get the link to activate...i think i ended in my junk mail which i threw away like a dumb *** but i did email you and you asked me what handle did i use?...im not too sure what you meant by that!...help...i would like to start logging
thanks
bobby
"So drivability quirks usually are explained away as "The cost of driving a modified car"
That hits the nail on the head. I wish more professional tuners would work out more of the drivability quirks, and not just tune for power.
I have all the equipment to mess with the ECU myself, and I wouldent mind seeing seeing maps posted before and after they fixed some of the drivability quirks.
Once I move to Guam I might have to teach myself how to do some basic tuning, rignt now I just don't have the time and place to teach myself.
That hits the nail on the head. I wish more professional tuners would work out more of the drivability quirks, and not just tune for power.
I have all the equipment to mess with the ECU myself, and I wouldent mind seeing seeing maps posted before and after they fixed some of the drivability quirks.
Once I move to Guam I might have to teach myself how to do some basic tuning, rignt now I just don't have the time and place to teach myself.
although this is a good write up on "how to" im a little confused about tuning afrs first?...would you actually turn up the boost to the desired psi and slowly adjust fuel to the target afrs?...or tune for target afrs, but wouldn't the boost pressure increase lean the target afrs? im a noob at tuning and would like the advice from others who would like to learn just like me...i also dont have any tuners in site for another 300miles...
--malibujack i also registered on aktivematrix but did not get the link to activate...i think i ended in my junk mail which i threw away like a dumb *** but i did email you and you asked me what handle did i use?...im not too sure what you meant by that!...help...i would like to start logging
thanks
bobby
--malibujack i also registered on aktivematrix but did not get the link to activate...i think i ended in my junk mail which i threw away like a dumb *** but i did email you and you asked me what handle did i use?...im not too sure what you meant by that!...help...i would like to start logging
thanks
bobby
I do it in two stages so I don't accidentally go too lean.. If the boost level is going to be a large jump, then I set the boost a little higher than I had previously, then I set the AFR a bit richer, then raise the boost again and set it again. This way a large jump doesn't "catch you offguard" The good news is the factory maps are insanely rich, and you probably can turn up the boost without going too lean, then make your AFR, finally Timing, then fine-tune both as required.. I know the "Simple and In a nutshell response" really makes it seem very basic, and in reality it is, but takes time and a little patience.
Just remember to keep checking your AFR's as timing will have an affect on AFR also, the more timing you have the more complete a burn, etc.. If you can monitor EGT's they also correlate to this and allows you to more easily find a good timing/afr balance that doesn't result in high EGT's means that more energy is being used for power, and not wasted as heat (old school tuning approach, but its still good to use if you have the data available) Not to mention too much heat can hurt stuff.
Mivec tuning is a bit of an art, and as far as I can tell, there is room for creativity. There is A LOT to be gained with modifying it. I used a map in the thread listed above and made 274 awhp bone stock (up from 251).
There is a guy by the name of JohnBradley that has done quite a bit of research on this topic, and with one of his maps I made 325 awhp with a tbe, mbc, and an intake. Take a look at that thread, as it is pretty comprehensive. Perhaps there are other threads that I have not seen that someone can post up.
Its funny, I'm still a little baffled by the MIVEC tuning.. But I don't have an IX so I won't have much opportunity to learn about it until I begin tuning a few local IX's.. Its not that I don't understand the technology, or how it works. Just that I don't like relying on other people for information on what works. Same reason I spent my own time experimenting with cam gear settings.
Those are impressive numbers. I'll read the article.. thank you for the link.
There are entire threads dedicated to this subject. Most of them are okay. Here is one that I think is particularly developed.
Mivec tuning is a bit of an art, and as far as I can tell, there is room for creativity. There is A LOT to be gained with modifying it. I used a map in the thread listed above and made 274 awhp bone stock (up from 251).
There is a guy by the name of JohnBradley that has done quite a bit of research on this topic, and with one of his maps I made 325 awhp with a tbe, mbc, and an intake. Take a look at that thread, as it is pretty comprehensive. Perhaps there are other threads that I have not seen that someone can post up.
Mivec tuning is a bit of an art, and as far as I can tell, there is room for creativity. There is A LOT to be gained with modifying it. I used a map in the thread listed above and made 274 awhp bone stock (up from 251).
There is a guy by the name of JohnBradley that has done quite a bit of research on this topic, and with one of his maps I made 325 awhp with a tbe, mbc, and an intake. Take a look at that thread, as it is pretty comprehensive. Perhaps there are other threads that I have not seen that someone can post up.
Thread Starter
Evolving Member
iTrader: (19)
Joined: Jan 2007
Posts: 400
Likes: 0
From: Lawrence, IN
Unless you look at it as lower boost = 10 or 11psi versus 22 or 23 psi?? But I tend to think more boost is better as the more air you have the more fuel you can have the more power you will get, up to certain harware limitations of course.