Where can i learn how to map my own car.

Where can i learn how to map my own car.

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stevieturbo

17,229 posts

246 months

Saturday 24th October 2015
quotequote all
Evoluzione said:
Would you run through how to set up the idle on mine if I post up some some info? Would be good to learn some easy stuff as i'm completely lost with ECUs. I just feel the cold start idle is a little high (circa 1800 rpm) and don't think the ICV should be running all the time (even when hot). Warm idle is fine. On the OE system I believe the ICV is switched off when warm because when you unplug it it makes no difference, I prefer this (less component wear).
It's really going to depend on the ecu and what or how it controls idle !

Simplest thing is to turn idle control to either off, or a very low static duty, say 10% and then set base hot idle via the throttle blade, and/or a sensible level of timing for your idle.

After that just use idle control to increase for a fast idle when cold. In theory your idle should never really be able to fall below this base level even with a closed valve.

Or set base idle with valve duty etc at say 20-50% static ( try and see what works best for you ), and have a slightly fast mechanical idle via the blade, and then hot idle control pulls rpm down a bit to your desired idle speed and cold idle will allow it to run a bit higher.

That way when idle control is off, base rpm will be slightly higher, so when pulling up to junctions etc, or revving and allowing it to fall to idle...it will fall to that higher rpm, then idle control will have to pull it down to idle. AGain the latter can offer less chance of stalling

Evoluzione

10,345 posts

242 months

Saturday 24th October 2015
quotequote all
stevieturbo said:
Evoluzione said:
Would you run through how to set up the idle on mine if I post up some some info? Would be good to learn some easy stuff as i'm completely lost with ECUs. I just feel the cold start idle is a little high (circa 1800 rpm) and don't think the ICV should be running all the time (even when hot). Warm idle is fine. On the OE system I believe the ICV is switched off when warm because when you unplug it it makes no difference, I prefer this (less component wear).
It's really going to depend on the ecu and what or how it controls idle !

Simplest thing is to turn idle control to either off, or a very low static duty, say 10% and then set base hot idle via the throttle blade, and/or a sensible level of timing for your idle.

After that just use idle control to increase for a fast idle when cold. In theory your idle should never really be able to fall below this base level even with a closed valve.

Or set base idle with valve duty etc at say 20-50% static ( try and see what works best for you ), and have a slightly fast mechanical idle via the blade, and then hot idle control pulls rpm down a bit to your desired idle speed and cold idle will allow it to run a bit higher.

That way when idle control is off, base rpm will be slightly higher, so when pulling up to junctions etc, or revving and allowing it to fall to idle...it will fall to that higher rpm, then idle control will have to pull it down to idle. AGain the latter can offer less chance of stalling
I'll start a new thread; Map your car blind with Stevie the Wonderwink
What I can't see is how the ICV can lower the idle below what the plate allows? Surely it can only increase? It's the same type as the old Ford Cosworth ones btw.

stevieturbo

17,229 posts

246 months

Saturday 24th October 2015
quotequote all
Evoluzione said:
I'll start a new thread; Map your car blind with Stevie the Wonderwink
What I can't see is how the ICV can lower the idle below what the plate allows? Surely it can only increase? It's the same type as the old Ford Cosworth ones btw.
It depends what position the ICV is for any base idle. If it's say 50% open, then it gives the potential to go either way.

If it's fully closed, then no that valve would not have any means to reduce idle speed

There are many IF's and variables.

Steve_D

13,737 posts

257 months

Sunday 25th October 2015
quotequote all
With the engine fully warm set the ICV fully closed or blank it off then set the base idle using the throttle plate stop screw. Set the idle as low as you can get it without the engine dying.

When the ICV is back in operation it will be able to control idle right down to your new base but you are unlikely to need to be there. Normal warm idle will be with a few percentage of ICV.

Steve

Evoluzione

10,345 posts

242 months

Sunday 25th October 2015
quotequote all
Steve_D said:
With the engine fully warm set the ICV fully closed or blank it off then set the base idle using the throttle plate stop screw. Set the idle as low as you can get it without the engine dying.

When the ICV is back in operation it will be able to control idle right down to your new base but you are unlikely to need to be there. Normal warm idle will be with a few percentage of ICV.

Steve
It isn't the physics of it that is the problem, I can do that easy enough, it's the computer side of things where the problems are.

Evoluzione

10,345 posts

242 months

Sunday 25th October 2015
quotequote all
stevieturbo said:
It depends what position the ICV is for any base idle. If it's say 50% open, then it gives the potential to go either way.

If it's fully closed, then no that valve would not have any means to reduce idle speed

There are many IF's and variables.
Sorry I read your post as if you were suggesting the ICV could bring the rpm below what the throttle plate would allow, I can see what you mean now. So basically the ICV does run all the time. I'll get some screen shots up later so you can see what i'm looking at, but basically I have:

ICV cooling fan offset % (this is I can understand)
ICV Dashpot % (no idea)
ICV Integral gain (no idea)
ICV Proportional gain (no idea)
Idle control base spark advance (degrees) (No idea)
Idle control proportional spark advance (deg) no idea
Target idle speed (this is the one we'll probably do?)

stevieturbo

17,229 posts

246 months

Sunday 25th October 2015
quotequote all
Evoluzione said:
Sorry I read your post as if you were suggesting the ICV could bring the rpm below what the throttle plate would allow, I can see what you mean now. So basically the ICV does run all the time. I'll get some screen shots up later so you can see what i'm looking at, but basically I have:

ICV cooling fan offset % (this is I can understand)
ICV Dashpot % (no idea)
ICV Integral gain (no idea)
ICV Proportional gain (no idea)
Idle control base spark advance (degrees) (No idea)
Idle control proportional spark advance (deg) no idea
Target idle speed (this is the one we'll probably do?)
No, the ICV "may" operate all the time...again it depends on the ecu/valve etc. Some will simply ignore it above certain thresholds, some may hold it at a certain position above certain thresholds, and it also looks like your ecu offers ignition advance as a means of idle control too. So you've two things to deal with that can affect idle speed.

So it may be able to add/reduce the amount of air via the mechanical valve, and also add/remove timing directly in order to try and achieve any idle speed targets.
Timing generally works faster but with less overall range, air bypass valve offers larger ranges of control, although can be perhaps a little harder to get right.

IMO turn off all forms of closed loop control, fix the ICV to a low static position eg 10% and then adjust blade opening for a good solid hot idle. Then idle control should have a minimal amount of work to do most of the time.
I would not unplug or blank off the ICV for this base setting, as there is no guarantee that under ecu control it would ever see that same condition.

anonymous-user

53 months

Sunday 25th October 2015
quotequote all
Evoluzione said:
ICV cooling fan offset % (this is I can understand)
This is to elevate idle speed when the cooling fans are running, either to avoid hot stalls or to provide a higher alternator output to cope with the extra current demand of the fans


Evoluzione said:
ICV Dashpot % (no idea)
"dashpot" is a hang up from the days of carbs, where the throttle was held open on tipouts by an oil filled damper! The name has stuck, but in these days of EMS, it simply refers to limiting the rate of closure of the throttle. This is critical because it controls how rapidly the engine is allowed to go to zero and then negative torque. (affects chassis balance / shunt-shuffle on tip outs etc) Typically, when used with an idle control valve, as soon as the throttle is open enough to render the ICV non effective (usually over about 10% throttle plate position) the ICV is wound fully open and held there. When you suddenly lift off, the icv is fully open, and how fast it shuts is controlled by the dashpot function. Too much dashpot and the car feels like it's "running away" on closed throttle, too little and the chassis can get twitchy!

Evoluzione said:
ICV Integral gain (no idea)
ICV Proportional gain (no idea)
Google "PID" tuning basics! It's actually really simple. The ICV position will be driven by the error in the idle speed. The proportional term is controlling the output vs the current error. The Integral term is the error "history" and is used to drive the error to zero over time.

Evoluzione said:
Idle control base spark advance (degrees) (No idea)
I imagine this is the basic ignition angle to use when the idle control system is active. (rather than use the base map)


Evoluzione said:
Idle control proportional spark advance (deg) no idea
This is the Proportional gain of the idle speed error. A larger gain value means the system responds more aggressively to idle speed errors. In this case it is driving the ignition angle trim to attempt to keep idle speed within limits (ignition is "fast path" as it can be trimmed on a firing event basis. Air (via ICV) is the "slow path" as it takes some time to change the manifold pressure and hence affect torque)


Evoluzione said:
Target idle speed (this is the one we'll probably do?)
The basic idle speed setpoint. Presumably vs coolant temp?

Evoluzione

10,345 posts

242 months

Monday 26th October 2015
quotequote all
Max_Torque said:
Evoluzione said:
ICV cooling fan offset % (this is I can understand)
This is to elevate idle speed when the cooling fans are running, either to avoid hot stalls or to provide a higher alternator output to cope with the extra current demand of the fans


Evoluzione said:
ICV Dashpot % (no idea)
"dashpot" is a hang up from the days of carbs, where the throttle was held open on tipouts by an oil filled damper! The name has stuck, but in these days of EMS, it simply refers to limiting the rate of closure of the throttle. This is critical because it controls how rapidly the engine is allowed to go to zero and then negative torque. (affects chassis balance / shunt-shuffle on tip outs etc) Typically, when used with an idle control valve, as soon as the throttle is open enough to render the ICV non effective (usually over about 10% throttle plate position) the ICV is wound fully open and held there. When you suddenly lift off, the icv is fully open, and how fast it shuts is controlled by the dashpot function. Too much dashpot and the car feels like it's "running away" on closed throttle, too little and the chassis can get twitchy!

Evoluzione said:
ICV Integral gain (no idea)
ICV Proportional gain (no idea)
Google "PID" tuning basics! It's actually really simple. The ICV position will be driven by the error in the idle speed. The proportional term is controlling the output vs the current error. The Integral term is the error "history" and is used to drive the error to zero over time.

Evoluzione said:
Idle control base spark advance (degrees) (No idea)
I imagine this is the basic ignition angle to use when the idle control system is active. (rather than use the base map)


Evoluzione said:
Idle control proportional spark advance (deg) no idea
This is the Proportional gain of the idle speed error. A larger gain value means the system responds more aggressively to idle speed errors. In this case it is driving the ignition angle trim to attempt to keep idle speed within limits (ignition is "fast path" as it can be trimmed on a firing event basis. Air (via ICV) is the "slow path" as it takes some time to change the manifold pressure and hence affect torque)


Evoluzione said:
Target idle speed (this is the one we'll probably do?)
Thanks for taking the time to explain, but what is a 'tip out'?

I think the last few posts really just outline how difficult it is, learning to speak and write Chinese would be infinitely easier.

If you were to start say, building engines then your average home mechanic or petrolhead could open an engine and point out the basic parts (crankshaft, piston, block, valves etc). You then progress to the materials and their qualities, what the components do, how to assemble correctly etc and then possibly onto modifying. It's all relatively intuitive and researchable, but with ECU tuning you can open the actual ECU or look at the map on a screen and not really recognise or understand any of it. You have to start to learn a new language.
You can't look in a book, nor 'Google' even the terms. I've looked at several books on mapping, the glossaries are short, the list of chapters simply do not contain something like 'How to set up the idle' and start with the basics.
As outlined earlier it's difficult to find a suitable course and even then, when tuning for power you need a dyno.
I think you have to be wired a certain way and have had a particular background (computers, electronics and engines) to be understanding it, let alone be any good at it. Like I've said before, I have nothing but massive admiration for those who can do it well and I don't think there are many around who can.

stevieturbo

17,229 posts

246 months

Monday 26th October 2015
quotequote all
Tip In generally refers to opening the throttle, tip out refers to closing it.

There may be books that cover some, but different ecu's just use different terminology. Some make sense, some make no sense at all.

Most should make some sort of sense with experience though...and of course previous experience when tuning carbs/dizzy's

If your background doesnt have all that experience as to how engines work, what they want in terms of fuel/spark etc...then it will of course be harder

SuperchargedVR6

3,138 posts

219 months

Monday 26th October 2015
quotequote all
Evoluzione said:
Max_Torque said:
Evoluzione said:
ICV cooling fan offset % (this is I can understand)
This is to elevate idle speed when the cooling fans are running, either to avoid hot stalls or to provide a higher alternator output to cope with the extra current demand of the fans


Evoluzione said:
ICV Dashpot % (no idea)
"dashpot" is a hang up from the days of carbs, where the throttle was held open on tipouts by an oil filled damper! The name has stuck, but in these days of EMS, it simply refers to limiting the rate of closure of the throttle. This is critical because it controls how rapidly the engine is allowed to go to zero and then negative torque. (affects chassis balance / shunt-shuffle on tip outs etc) Typically, when used with an idle control valve, as soon as the throttle is open enough to render the ICV non effective (usually over about 10% throttle plate position) the ICV is wound fully open and held there. When you suddenly lift off, the icv is fully open, and how fast it shuts is controlled by the dashpot function. Too much dashpot and the car feels like it's "running away" on closed throttle, too little and the chassis can get twitchy!

Evoluzione said:
ICV Integral gain (no idea)
ICV Proportional gain (no idea)
Google "PID" tuning basics! It's actually really simple. The ICV position will be driven by the error in the idle speed. The proportional term is controlling the output vs the current error. The Integral term is the error "history" and is used to drive the error to zero over time.

Evoluzione said:
Idle control base spark advance (degrees) (No idea)
I imagine this is the basic ignition angle to use when the idle control system is active. (rather than use the base map)


Evoluzione said:
Idle control proportional spark advance (deg) no idea
This is the Proportional gain of the idle speed error. A larger gain value means the system responds more aggressively to idle speed errors. In this case it is driving the ignition angle trim to attempt to keep idle speed within limits (ignition is "fast path" as it can be trimmed on a firing event basis. Air (via ICV) is the "slow path" as it takes some time to change the manifold pressure and hence affect torque)


Evoluzione said:
Target idle speed (this is the one we'll probably do?)
Thanks for taking the time to explain, but what is a 'tip out'?

I think the last few posts really just outline how difficult it is, learning to speak and write Chinese would be infinitely easier.

If you were to start say, building engines then your average home mechanic or petrolhead could open an engine and point out the basic parts (crankshaft, piston, block, valves etc). You then progress to the materials and their qualities, what the components do, how to assemble correctly etc and then possibly onto modifying. It's all relatively intuitive and researchable, but with ECU tuning you can open the actual ECU or look at the map on a screen and not really recognise or understand any of it. You have to start to learn a new language.
You can't look in a book, nor 'Google' even the terms. I've looked at several books on mapping, the glossaries are short, the list of chapters simply do not contain something like 'How to set up the idle' and start with the basics.
As outlined earlier it's difficult to find a suitable course and even then, when tuning for power you need a dyno.
I think you have to be wired a certain way and have had a particular background (computers, electronics and engines) to be understanding it, let alone be any good at it. Like I've said before, I have nothing but massive admiration for those who can do it well and I don't think there are many around who can.
Tip out is the opposite of tip in, i.e. how much fuel to remove when the throttle is snapped shut. Not all engines need it, but it fills in the gap from sudden throttle closure to over run. Tip in (aka enrichment pump) is usually the one people focus on as it stops the engine from stuttering at high load, low road speed conditions when you slam the throttle open. Being momentarily rich between load sites coming off the gas isn't usually a massive deal on a lot of engines, unless you're trying to protect the cat.

Yep, sometimes you have to think like a computer as well as engine when mapping, but you don't need a degree in either to be honest. Some ECU makers use their own terminology, but it's essentially the same stuff underneath. It will all start to make sense when you start playing with an ECU.

If you're mapping for the road, have a clear objective at the start. Such as good idle, no stalling, no jerkiness on part throttle etc etc. Then you can start choosing your components and ECU. I.e. no lumpy cams, do you have DBW, direct injection etc etc. ECUs are just like any other tool and choose the right one for the job at hand.





Edited by SuperchargedVR6 on Monday 26th October 11:01

Evoluzione

10,345 posts

242 months

Monday 26th October 2015
quotequote all
If I have time later I'll plug my lappy in have a look at what to do with basic idle and relay it here and you can make of it what you will.

Another thing i'd like to do is to have some basic form of boost control, right now it's using just a basic ball & spring valve which does the job albeit rather crudely and not very well.
Here is what I'd like to do:

Reduce boost in first and second gears to stop wheel spin.
Even out the power curves.



I would prefer a straight line from the first peak to the second peak if possible? I feel the valve is releasing suddenly, causing the WG to open just as quickly and causing the trough, before it gathers it up again.

I'd like to use an ABS sensor on the back wheel to tell the ECU road speed, boost control will be by Macvalve. The car no longer has ABS so if we can find out how to make the existing 2 wire Bosch sensor speak to the ECU then onto the Macvalve it would be good.
I know It's basic, but then sensible to start with something easy for now.

andygtt

8,344 posts

263 months

Monday 26th October 2015
quotequote all
lanan said:
Long time speaky smile

Try giving Sam Borgman at http://www.tdi-plc.com/about-academy-of-motorsport... a call.
A top chap
Sam maps my car... its the curve and way power is delivered when using the throttle that has the most impact on acceleration. Sam's excellent on doing this and I have had a lot of people map the same car over the years.

Silent1

Original Poster:

19,761 posts

234 months

Monday 26th October 2015
quotequote all
andygtt said:
lanan said:
Long time speaky smile

Try giving Sam Borgman at http://www.tdi-plc.com/about-academy-of-motorsport... a call.
A top chap
Sam maps my car... its the curve and way power is delivered when using the throttle that has the most impact on acceleration. Sam's excellent on doing this and I have had a lot of people map the same car over the years.
Thanks chaps, that sounds like a good starting point, I think an aftermarket ecu might be a good idea as then as I move into other cars (of my own) I can take some knowledge with me.

anonymous-user

53 months

Monday 26th October 2015
quotequote all
There not really any "magic" to mapping, certainly not at the simple (aftermarket) end of the spectrum when even the "trick" systems only have a few maps (compared to a modern Torque based OEM EMS)

The important things to learn / understand is that really there are only 3 main things to control on an ICE:

1) The amount of air being ingested
2) The Amount of fuel being injected
3) The crank Angle at which the fire is lit!


Everything else is secondary. However, a lot of different effects interact, and the more complex and controllable the engine in question is, the more 'degrees of freedom' you must take account of.

What amazes me is the number of aftermarket "mappers" who don't actually understand, at a physical level, how an ICE operates, and as such, always struggle to correctly optimise the control system!

bearman68

4,642 posts

131 months

Monday 26th October 2015
quotequote all
Check out Viezu technologies. They train map makers, and will train you for a cost.

They will teach you the hardware and software, and programe interfaces.

Cheers

stevieturbo

17,229 posts

246 months

Monday 26th October 2015
quotequote all
Evoluzione said:
If I have time later I'll plug my lappy in have a look at what to do with basic idle and relay it here and you can make of it what you will.

Another thing i'd like to do is to have some basic form of boost control, right now it's using just a basic ball & spring valve which does the job albeit rather crudely and not very well.
Here is what I'd like to do:

Reduce boost in first and second gears to stop wheel spin.
Even out the power curves.



I would prefer a straight line from the first peak to the second peak if possible? I feel the valve is releasing suddenly, causing the WG to open just as quickly and causing the trough, before it gathers it up again.

I'd like to use an ABS sensor on the back wheel to tell the ECU road speed, boost control will be by Macvalve. The car no longer has ABS so if we can find out how to make the existing 2 wire Bosch sensor speak to the ECU then onto the Macvalve it would be good.
I know It's basic, but then sensible to start with something easy for now.
You can of course do everything you want....if your ecu allows you to do it.

And just because the power graph looks like that, doesnt mean it's the boost control causing it. Do you have a boost trace from that same run ?

And yes the ABS sensor should be able to keep most ecu's happy for a speed signal, although undriven wheel can sometimes be better.

Evoluzione

10,345 posts

242 months

Monday 26th October 2015
quotequote all
stevieturbo said:
You can of course do everything you want....if your ecu allows you to do it.

And just because the power graph looks like that, doesnt mean it's the boost control causing it. Do you have a boost trace from that same run ?

And yes the ABS sensor should be able to keep most ecu's happy for a speed signal, although undriven wheel can sometimes be better.
Yes I've just got to work out how to do it!
It is an undriven wheel I'm thinking of, here is a graph:



The pressure does take a bit of a dip, but doesn't seem as much as the power does though, what you thinking?
I've noticed a lot of turbo cars seem to do it.

anonymous-user

53 months

Monday 26th October 2015
quotequote all
Be careful of "correcting" driveability issues that are actually chassis rolls artifacts! ie, the power curve often takes a dip after turbo spool up on chassis rolls because the the speed control loop on the rolls taking torque off after it's applied a big wodge (<< technical term!) of retardation to try to keep to it's pre-programmed accelerate rate during the sudden torque ramp on.


Get some proper on track logs of the boost control data, in various gears, and with various different tip in conditions before jumping to conclusions!

If you do have significant boost overshoot (which of course does make the car faster / feel fast, unless it results in wheelspin) then you'll almost certainly have to develop a better open loop boost control valve feed forward table BEFORE you re-tune the PIDs (the closer to target the open loop parameters are, the less work the closed loop terms will have to do, and the smaller the error, and the less likely the system will suffer from phase lag or oscillation etc)

Remember also that there is no point doing the boost control mapping before you have optimised and validated the ignition timing (as exhaust energy is inversely proportional to ignition angle. ie. you retard the ignition, the fuel air charge burns later, so more heat (and hence energy) goes out the exhaust port) For perfect control under all operating conditions, your feed forward boost control tables will need to have an ignition angle trim.

Edited by anonymous-user on Monday 26th October 22:47

anonymous-user

53 months

Monday 26th October 2015
quotequote all
Also worth noting, that unless you have a very long 1st and 2nd gear, in most cases you will always be under target boost in low gears anyway (because the engine accelerates "away" from the turbo before it can catch up! if you want to map "steady state" boost in low gears, you will have to do this on the road against the brakes (usual caveats on safety etc apply!) or up a very steep hill (or with a trailer dyno)