Live mapping tutorial by Stu.... Discussion Required
22-11-2005, 10:26 AM
#405
Originally Posted by Fast Guy
So can you tell exactly what power the car has and even draw a torque/power curve from the fuelling map?
Combine it with the ignition map and you could get a little closer, add in some specific experience with the engine in question and you would get a little closer again.
Do a leakdown test so you can see a bit about the condition of the engine and you would get a little closer again.
Combine this with technical spec of the turbo, and the inlet temps etc and it gets closer again
So for example, if you gave someone like Stu who has a LOT of experience with cossies a cossie fuel and ignition map and leakdown data, im sure he could guestimate it very well.
BUT its still only ever going to be a guess, it would also vary based on cam timing etc too.
22-11-2005, 12:02 PM
#406
Hope you dont mind stu, but ive copied and pasted your chapters you wrote and stuck them on the vauxhall forum as live mapping was being discussed recently so i thought it would be a good time to share some details of what it involves.
http://www.migweb.co.uk/forums/showthread.php?t=236319
http://www.migweb.co.uk/forums/showthread.php?t=236319
22-11-2005, 04:05 PM
#408
PassionFord Post Troll
Right, moved here from "ways to combat det" post.
I've been haveing a go at a bit of DIY mapping. Full story can be found on above post.
Stu, Chip, Gareth T and others have been most helpful.
Here is my ignition map that we have been discussing.
and the printout from the dyno run.
I've been haveing a go at a bit of DIY mapping. Full story can be found on above post.
Stu, Chip, Gareth T and others have been most helpful.
Here is my ignition map that we have been discussing.
and the printout from the dyno run.
22-11-2005, 04:13 PM
#410
Originally Posted by GARETH T
shall we get different ignition maps on here with specs and talk about why and where? 
22-11-2005, 04:20 PM
#411
PassionFord Post Troll
Originally Posted by GARETH T
shall we get different ignition maps on here with specs and talk about why and where?
Any one got one their willing to submit?
22-11-2005, 04:25 PM
#412
PassionFord Post Troll
Originally Posted by chip-3door
Originally Posted by GARETH T
shall we get different ignition maps on here with specs and talk about why and where?
22-11-2005, 04:35 PM
#413
Would it be worth me mentioning really basic stuff like the fact the numbers are higher on the right than the left is that as RPM increases the volumetric efficiency of the engine naturally tails off thus resulting in a less full cylinder each cycle, hence being able to handle more advance as the PCP's will otherwise naturally start to get too late in the cyle and the power will fall off?
And obviously the same reason is true for why the numbers are higher at the bottom (less boost) than the top?
Or do we assume anyone who has read this far in knows the basics?
Is that the sort of "golden rule" you meant Stu, or something a bit more advacned than that?
Like maybe go into how cam timing effects it, or something like that?
And obviously the same reason is true for why the numbers are higher at the bottom (less boost) than the top?
Or do we assume anyone who has read this far in knows the basics?
Is that the sort of "golden rule" you meant Stu, or something a bit more advacned than that?
Like maybe go into how cam timing effects it, or something like that?
22-11-2005, 04:42 PM
#414
Professional Waffler
Would it be worth me mentioning really basic stuff like the fact the numbers are higher on the left than the right is that as RPM increases the volumetric efficiency of the engine naturally tails off thus resulting in a less full cylinder each cycle
22-11-2005, 04:43 PM
#416
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Originally Posted by Stu @ M Developments
Ok,
Detonation in an engine is usually very slight.
A very slight problem will only usually
kill an engine if it occurs for a sustained
period. So if we have say, det at 5500rpm (common for YB).
In 1st gear flat out she spends maybe, what? 1/4 second there?
In 3rd gear flat out she spends maybe, what? 1.5 seconds there?
In 5th gear flat out she spends maybe, what? 5 seconds there?... Boom.
Hope this helps somewhat.
Detonation in an engine is usually very slight.
A very slight problem will only usually
kill an engine if it occurs for a sustained
period. So if we have say, det at 5500rpm (common for YB).
In 1st gear flat out she spends maybe, what? 1/4 second there?
In 3rd gear flat out she spends maybe, what? 1.5 seconds there?
In 5th gear flat out she spends maybe, what? 5 seconds there?... Boom.
Hope this helps somewhat.
so is 5 seconds of even 'Slight' det enough to kill an engine!!?
( this thread is just serving to worry me how engines/maps can go wrong so easy!!!! lol)
also, a questions on fuelling,
(again i am someone knowing very little about maps etc)
I am lead to believe that optimum AFR is around 14.5:1?
(unsure if that is correct!?)
IS this the aim of the 'best fuel map?' to Keep the
AFR at the optimum figure at all times?
or is there conditions where a richer or leaner AFR would be
more ideal?
just wondering! thanks!
PS: very interesting thread!!
22-11-2005, 04:45 PM
#417
The problem is that during those 5 seconds it could be enough to start the headgaskt on its way, and it then fails 2 months later as a result
But it really depends on how slight the slight det is of course.
But it really depends on how slight the slight det is of course.
22-11-2005, 04:47 PM
#418
IS this the aim of the 'best fuel map?' to Keep the
AFR at the optimum figure at all times?
or is there conditions where a richer or leaner AFR would be
more ideal?
AFR at the optimum figure at all times?
or is there conditions where a richer or leaner AFR would be
more ideal?
Optimum fuel economy is leaner than optimum power.
Depends on what you are mapping for.
Typcially it will be a bit of both, at different points in the rev range, well on a road car anyway.
22-11-2005, 04:54 PM
#420
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Originally Posted by chip-3door
Optimum for what?
Optimum fuel economy is leaner than optimum power.
Depends on what you are mapping for.
Typcially it will be a bit of both, at different points in the rev range, well on a road car anyway.
Optimum fuel economy is leaner than optimum power.
Depends on what you are mapping for.
Typcially it will be a bit of both, at different points in the rev range, well on a road car anyway.
looking at it for gettting optimum performace really..
is it difficult to achieve keeping AFR right (mapping say an L8)
am i right in thinking there are only a rather limited number of mappable points?
(as said know nothing of maps ECUs etc, just trying to grasp somethings ive been wondering about!)
with ecus
22-11-2005, 07:51 PM
#424
I am well pleased to see this topic back in action, makes a great change from the drivel ive been reading lately!! 
Chip, you getting into that now will make me a happy man as people will be able to learn and get back into this topic, and i will have less to do to keep it alive 
I will still be here with my own input, but i dont have the time free at the moment for essays, or TBH the enthusiasm, due to what i mentioned the other night. Normal service will soon be resumed though...
Originally Posted by chip-3door
Would it be worth me mentioning really basic stuff like the fact the numbers are higher on the right than the left is that as RPM increases the volumetric efficiency of the engine naturally tails off thus resulting in a less full cylinder each cycle, hence being able to handle more advance as the PCP's will otherwise naturally start to get too late in the cyle and the power will fall off?
And obviously the same reason is true for why the numbers are higher at the bottom (less boost) than the top?
Or do we assume anyone who has read this far in knows the basics?
Is that the sort of "golden rule" you meant Stu, or something a bit more advacned than that?
Like maybe go into how cam timing effects it, or something like that?
And obviously the same reason is true for why the numbers are higher at the bottom (less boost) than the top?
Or do we assume anyone who has read this far in knows the basics?
Is that the sort of "golden rule" you meant Stu, or something a bit more advacned than that?
Like maybe go into how cam timing effects it, or something like that?
I will still be here with my own input, but i dont have the time free at the moment for essays, or TBH the enthusiasm, due to what i mentioned the other night. Normal service will soon be resumed though...
22-11-2005, 07:55 PM
#425
Originally Posted by pee vee
is it difficult to achieve keeping AFR right (mapping say an L8) am i right in thinking there are only a rather limited number of mappable points?
22-11-2005, 07:57 PM
#426
Originally Posted by Garage19
He did mention something about explaining golden rules which would be cool, but i wouldn't expect him to start giving away too many secrets. I now realise how much research/development it takes to be able get the best out of ign/fueling on each car.
You should learn why the correct advance table will show some "Curves"
23-11-2005, 12:08 PM
#429
Ok, well here goes in a little more detail, although im afraid i cant match Stu on either writing style or depth of knowledge (although by the sounds of that line i can compete with the best of them when it comes to a thorough rim job 
)
WHAT IS VOLMENTRIC EFFICIENCY? (VE)
The volumetric efficiency of an engine is basically a % value representing how well it has managed to fill its cylinders in a cycle.
Now, picture an engine sat there on your bench at home.
You slowly turn it over, as the piston comes down and the valve opens it draws in air to fill the cylinder.
First thought is that it will draw in 500cc (in a 2 litre) of air exactly, as thats the amount of space there is available to fill.
However this wont be the case in reality.
The reason is that the valve is never open till EXACTLY the bottom of the cylinder, and if it either stay open after bottom dead centre or shuts before bottom dead centre it means that you have sealed in the amount of air at that point in the cycle instead.
Now, complicate things further by having this happen very quickly (the engine turning over i mean, instead of you doing it slowly by hand), this will drop the VE even further because the cylinder wont have time to fill properly.
So from that, you can see that as RPM increases, the VE will naturally drop in this simple example.
So why does Stu mention it being a curve, surely thats just a pretty much linear result???
Well, in that simple example yes, but in the real world things are far more dynamic than this simple example.
Im actually NOT going to go into a massive amount of detail on this as TBH it would end up longer than this topic is so far if we start getting down to thing like reversion at the valves and cam overlap etc.
But suffice to say that based on the specs of the cams (in terms of lift and duration) and the amount of overlap dialled into the cams, its going to effect the VE differently at different points in the rev range, port size in the head is another of these factors, and the reason why when you port a head you need a remap all the way up, its NOT just that a ported head means it breathes higher up the top, it can actually make it breath LESS well lower down, especially off boost, due to drops in gas speed.
HOW DOES THIS EFFECT THE MAPPING REQUIREMENTS OF THE ENGINE?
If any of you have had a very hot cam in a normally aspirated motor you will have noticeabley felt it "come on cam" at a point in the rev range, thats the point at which the VE suddently increases dramatically, and this will show up as an increase in torque, but in terms of the mapping (what this topic is about) it will require:
more fuel
less timing
So you will find that on many ignition maps you will get a line that starts to increase, then levels off, (or even goes back down in an extreme case!) and then starts to increase again as the RPM continues to rise still further.
The fuelling obviously will basically be a mirror image of this, with more fuel required at the points of higher VE where less timing is required. (well in our oversimplified example anyway, lol)
WHY ARE THE NUMBER OF LOAD SITES SO IMPORTANT?
This again points towards why its SO important to have as many map points as possible and why you need to have them positioned in the correct places to allow the interpolation between them to be as near to correct as possible.
Imagine this sitation, a peak in VE at 5500 rpm, and map points every 1000rpm.
What is going to happen is that you want timing of 12 degrees at 5000, 10 degrees at 5500, then back to 12 degrees at 6000. (for example, not actual figures from any specific engine!)
In order to avoid Det on that engine on 1000rpm increments you are going to have NO CHOICE but to dial in 10 degrees of timing at 5000 and 6000, costing you both economy and horsepower through that hole chunk of the rev range with the excepction of the 5500 point.
Obviously if you could move the load site to where this peak is, then even on the same number of sites, you can still manage to better map it.
)WHAT IS VOLMENTRIC EFFICIENCY? (VE)
The volumetric efficiency of an engine is basically a % value representing how well it has managed to fill its cylinders in a cycle.
Now, picture an engine sat there on your bench at home.
You slowly turn it over, as the piston comes down and the valve opens it draws in air to fill the cylinder.
First thought is that it will draw in 500cc (in a 2 litre) of air exactly, as thats the amount of space there is available to fill.
However this wont be the case in reality.
The reason is that the valve is never open till EXACTLY the bottom of the cylinder, and if it either stay open after bottom dead centre or shuts before bottom dead centre it means that you have sealed in the amount of air at that point in the cycle instead.
Now, complicate things further by having this happen very quickly (the engine turning over i mean, instead of you doing it slowly by hand), this will drop the VE even further because the cylinder wont have time to fill properly.
So from that, you can see that as RPM increases, the VE will naturally drop in this simple example.
So why does Stu mention it being a curve, surely thats just a pretty much linear result???
Well, in that simple example yes, but in the real world things are far more dynamic than this simple example.
Im actually NOT going to go into a massive amount of detail on this as TBH it would end up longer than this topic is so far if we start getting down to thing like reversion at the valves and cam overlap etc.
But suffice to say that based on the specs of the cams (in terms of lift and duration) and the amount of overlap dialled into the cams, its going to effect the VE differently at different points in the rev range, port size in the head is another of these factors, and the reason why when you port a head you need a remap all the way up, its NOT just that a ported head means it breathes higher up the top, it can actually make it breath LESS well lower down, especially off boost, due to drops in gas speed.
HOW DOES THIS EFFECT THE MAPPING REQUIREMENTS OF THE ENGINE?
If any of you have had a very hot cam in a normally aspirated motor you will have noticeabley felt it "come on cam" at a point in the rev range, thats the point at which the VE suddently increases dramatically, and this will show up as an increase in torque, but in terms of the mapping (what this topic is about) it will require:
more fuel
less timing
So you will find that on many ignition maps you will get a line that starts to increase, then levels off, (or even goes back down in an extreme case!) and then starts to increase again as the RPM continues to rise still further.
The fuelling obviously will basically be a mirror image of this, with more fuel required at the points of higher VE where less timing is required. (well in our oversimplified example anyway, lol)
WHY ARE THE NUMBER OF LOAD SITES SO IMPORTANT?
This again points towards why its SO important to have as many map points as possible and why you need to have them positioned in the correct places to allow the interpolation between them to be as near to correct as possible.
Imagine this sitation, a peak in VE at 5500 rpm, and map points every 1000rpm.
What is going to happen is that you want timing of 12 degrees at 5000, 10 degrees at 5500, then back to 12 degrees at 6000. (for example, not actual figures from any specific engine!)
In order to avoid Det on that engine on 1000rpm increments you are going to have NO CHOICE but to dial in 10 degrees of timing at 5000 and 6000, costing you both economy and horsepower through that hole chunk of the rev range with the excepction of the 5500 point.
Obviously if you could move the load site to where this peak is, then even on the same number of sites, you can still manage to better map it.
23-11-2005, 12:54 PM
#430
Slight side note this one, not sure if its welcome in this topic or not, so have done as a seperate post.
WHY ARE ALL CHIPS THAT YOU CAN BUY "OFF THE SHELF" NEVER EVER REALLY ANY GOOD?
Ok, so looking backat my previous post, you can see that cam timing is critical thing that effects the VE of an engine, and obviously we all know that CR plays a big part in determining how much ignition advance an engine can take in order to avoid the PCP being at the wrong time.
So lets apply that bit of logic to off the shelf chips and fitting them to an engine.
How is an off the shelf chip made?
Well fundamentally, they are made in exactly the same was as the live mapped chips we are talking about here, a tuner takes their given "mule motor" for testing, puts a certain spec of parts on it (or possibly uses a customer car of the correct spec) and they map a set of chips for it.
Then what?
Well, then they take account of the points i just made about cam timing and CR, as these are the two things that vary most from engine to engine (skimming a head for example is common practice and effects BOTH cr and cam timing)
So what do they do to "take account" of potential differences?
Well they aim safe, VERY fooking safe, after all whats going to ruin your reputation more, someone making 10bhp less than they could have done, or someone blowing their engine up?
So how do they "aim safe" with the chips?
Easy, they delibertely go through and richen the chip up, so that it runs more fuel than is needed, so that if your injectors are slightly down on flow, or your regulator isnt quite adjusted correctly, it will still avoid that leanout that can kill your engine.
Same for the timing, they take their nice "3 degrees from det" or whatever it is basemap and they take a HUGE chunk of timing off of it, like literally as much as half a dozen degrees in some cases!
This means if your CR is too high (4wd head on a 2wd bottom end or whatever) you still have some sort of hope of keeping your engine in one piece!
How well will it work on MY engine?
Well, the answer is (compared to a live map) probably not very well at all in reality!
But it should be nice and safe, and due to the increase in boost on a stage 3 chip or similar, you should get a good increase in power, but my god will you notice the difference when you get a live map (or custom chip) instead!
Are some better than others?
Yes, some tuners (Stu@MSD) for example, will ask a lot of questions about your car, and select a chip that better suits it so that it doesnt have to be too far in the safe direction, but its still always going to be that little bit safe no matter how much detail you give him, as he isnt going to want to kill your engine just cause you didnt know the head has been skimmed after all, so he will ALWAYS assume you are mistaken at least a little bit with what you tell him!
Why should i have my chip setup by a tuner?
Well see above basically, if you go to someone like stu, they can fit the chip, give it a go, and if its detting its tits off cause you happen to have an engine fitted with N/A pistons by mistake then at least it will get noticed before its too late, and you can either by a slightly different chip, or not buy one at all until your engine fault is corrected, same for if the fuel pump isnt up the job (or more usually the wiring) or the fuel pressure is wrong or whatever.
Thats a bit off topic though, so feel free to move to another topic "Off the shelf chips, why arent they the optimum" or something like that if you want.
WHY ARE ALL CHIPS THAT YOU CAN BUY "OFF THE SHELF" NEVER EVER REALLY ANY GOOD?
Ok, so looking backat my previous post, you can see that cam timing is critical thing that effects the VE of an engine, and obviously we all know that CR plays a big part in determining how much ignition advance an engine can take in order to avoid the PCP being at the wrong time.
So lets apply that bit of logic to off the shelf chips and fitting them to an engine.
How is an off the shelf chip made?
Well fundamentally, they are made in exactly the same was as the live mapped chips we are talking about here, a tuner takes their given "mule motor" for testing, puts a certain spec of parts on it (or possibly uses a customer car of the correct spec) and they map a set of chips for it.
Then what?
Well, then they take account of the points i just made about cam timing and CR, as these are the two things that vary most from engine to engine (skimming a head for example is common practice and effects BOTH cr and cam timing)
So what do they do to "take account" of potential differences?
Well they aim safe, VERY fooking safe, after all whats going to ruin your reputation more, someone making 10bhp less than they could have done, or someone blowing their engine up?
So how do they "aim safe" with the chips?
Easy, they delibertely go through and richen the chip up, so that it runs more fuel than is needed, so that if your injectors are slightly down on flow, or your regulator isnt quite adjusted correctly, it will still avoid that leanout that can kill your engine.
Same for the timing, they take their nice "3 degrees from det" or whatever it is basemap and they take a HUGE chunk of timing off of it, like literally as much as half a dozen degrees in some cases!
This means if your CR is too high (4wd head on a 2wd bottom end or whatever) you still have some sort of hope of keeping your engine in one piece!
How well will it work on MY engine?
Well, the answer is (compared to a live map) probably not very well at all in reality!
But it should be nice and safe, and due to the increase in boost on a stage 3 chip or similar, you should get a good increase in power, but my god will you notice the difference when you get a live map (or custom chip) instead!
Are some better than others?
Yes, some tuners (Stu@MSD) for example, will ask a lot of questions about your car, and select a chip that better suits it so that it doesnt have to be too far in the safe direction, but its still always going to be that little bit safe no matter how much detail you give him, as he isnt going to want to kill your engine just cause you didnt know the head has been skimmed after all, so he will ALWAYS assume you are mistaken at least a little bit with what you tell him!
Why should i have my chip setup by a tuner?
Well see above basically, if you go to someone like stu, they can fit the chip, give it a go, and if its detting its tits off cause you happen to have an engine fitted with N/A pistons by mistake then at least it will get noticed before its too late, and you can either by a slightly different chip, or not buy one at all until your engine fault is corrected, same for if the fuel pump isnt up the job (or more usually the wiring) or the fuel pressure is wrong or whatever.
Thats a bit off topic though, so feel free to move to another topic "Off the shelf chips, why arent they the optimum" or something like that if you want.
07-12-2005, 09:01 AM
#434
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Originally Posted by GARETH T
shall we get different ignition maps on here with specs and talk about why and where?
timing
afr
1.6 cvh, std compression, std cam, active knock control, DIY headwork, efi head and inlet, std. turbo, large-GRS, 1.5 bar boost max, MS-management. Been tested for 208hp at 1.1 bar boost.
14-12-2005, 09:53 PM
#435
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how do i find out what is a good air fuel ratio ?
for a standered cosworth stage 1 2 ect
and when on say a rolling road wil this move around ?
is there anything i can buy to check that i have good fueling through the rev range whilst driving up my local motor way ?
ie if i have the wrong afr then i can take it to a tuner
i do not wish to map anything my self im not rich
hope some one can help advise me
thanks alan
for a standered cosworth stage 1 2 ect
and when on say a rolling road wil this move around ?
is there anything i can buy to check that i have good fueling through the rev range whilst driving up my local motor way ?
ie if i have the wrong afr then i can take it to a tuner
i do not wish to map anything my self im not rich
hope some one can help advise me
thanks alan
16-12-2005, 10:26 AM
#438
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Chip or anyone else who knows for that matter,
Can you please explain a bit more about the 'Mappable point' in relation to the number of points.
I'd imagine that there will be a number considered perhaps too small to be useful enough, but wonder what about the other end, is there ever too many to be useful?
Can you offer up any comparisons of different Ecu's and their number of points???
Can you please explain a bit more about the 'Mappable point' in relation to the number of points.
I'd imagine that there will be a number considered perhaps too small to be useful enough, but wonder what about the other end, is there ever too many to be useful?
Can you offer up any comparisons of different Ecu's and their number of points???
15-10-2006, 06:08 PM
#440
stu asked me to pop this up so i thought id put it here . i run dta pp8 pro on my car and few of you know that stu,chip,gareth,dougy have taught me over the net how to ubderstabd how to use it heres some screen shots
fuel map
ignition map
now the zeitronixs wideband gauge and data logger
after 12 months i still got alot of issues(que the piss takes )
i still have no bottle with the ignition side of things just wxsperimenting with different types of det cans
that stu,chip,gareth,dougy have taught me over the net how to ubderstabd how to use it heres some screen shots fuel map
ignition map
now the zeitronixs wideband gauge and data logger
after 12 months i still got alot of issues(que the piss takes )
i still have no bottle with the ignition side of things just wxsperimenting with different types of det cans