Good mapping

[BabyGodzillaGTi-R]

Hey guys is there such thing as a "dummies/ idiot's guide to mapping ecus"?
Till today i've yet to come across a book like that.
Have anyone come across on the internet a good, comprehensive article or website on ecu mapping?
I've yet to come across 1 especially for dummies like me who know bugge r all about it.

So far the best i've read is megasquirt website.
U guys got anything to share?
cheers

 

[celicaGT4st205]

http://www.gtiroc.com/forums/showthread.php?t=32831

 

[Fusion Ed]

Just a quick pointer here. if you are flooring your R out of a bend you need the cars map to allow for the resistance that is being placed on the drivetrain this involves quite a few parameters that are very difficult to replicate on a rolling road, so I would agree fully that the car needs a good set up after the rolling eoad

Dont agree. You can simulate any load condition on a r/r infact more than you can in a car on the road, the only thing that most done have is a decent wind tunnel to simulate cooling as well.

 

[turblio]

Ed, the diffs on mine create varying torque and resistance as I turn left or right sometimes so much the wheels jump unless you know those torque equations you will not replicate nearside over offside diff resistance under power, there are so many other things to take into account as well, tyre grip for one, wheel size, suspension travel will affect cornering/tyre resistance put it this way, you could guess!...lol

 

[Keira]

frank...

the above is the dumbest thing i have ever read on the internet :lol:

how about if its raining and the weight of the water on the car then affects the power to weight ratio...:lol:

would you need a hose pipe aswell as the rollers to replicate that situation :lol:

 

[Fusion Ed]

Ed, the diffs on mine create varying torque and resistance as I turn left or right sometimes so much the wheels jump unless you know those torque equations you will not replicate nearside over offside diff resistance under power, there are so many other things to take into account as well, tyre grip for one, wheel size, suspension travel will affect cornering/tyre resistance put it this way, you could guess!...lol

None of this in any way affects how you map an engine. The engine has just one source of power out and that's via the crank. Any variations of loading regardless of how they are placed be it LSDs etc will only load certain cells on the map, all of which could be replicated with a r/r.

 

[turblio]

oh ok kieron thank you darling, and the words "could be replicated" are never going to happen as most rr would not bother would they? or to put it into perspective most would not know how to, and as for it not affecting the way you map an engine, come on Ed! lol

 

[Fusion Ed]

Its true that some RR operators simply map the main full load cells and miss allot of the others, quite because (in my opinion) people are not willing to pay or don't understand the time it takes to do it right.

Having any kind of diff or strange load on the engine doesn't suddenly throw the map into any cells it wouldn't other wise be able to get. Nor does it need anything magical to re-create this load. All you have to do on most eddy-current controlled dynos is just dial in an RPM load and then get it to hold this and you apply power and map each cell in that RPM column. proceed to do this through out the entire map, both for fuel and ignition and then go and work on the transient load fuel enrichment and other temp calibration maps (which will take a while)

 

[campbellju]

group hug gents. I don't think any of us would argue a RR creates a perfect map but if I had access to one I would do 90% of my work on that as its far easier and safer.

An RR can't easily mimic air flow through the engine bay and intercooler at different speeds and often the bonnet is left up which is even less realistic.

It can't mimic bits like the entance to the main straight at Cadwell over the weekend where it goes from high load to low load and back again in tenths of a second as you almost jump the brow. I think this is similar to what Frank is trying to say with his diffs.

Slightly less exciting I found a point on the map on the motorway going down hill at 60mph that was only normally found on the overrun but I could happily cruise at it.

Howerver, a road map isn't perfect though and the only way to slow tansitions through cells is to use 5th gear, find some good hills and/or left foot brake but one of those is quickly illegal.

 

[Fusion Ed]

totally agree with the above!! One day when I have my own r/r I'll invite all those who are interested in their own mapping to come and have a go if they wish. God knows when that will be though!

 

[stumo]

Jim, i've found a pair of pretty steep hills that should be perfect for holding back the cars...trouble is they're over an hour away.:sad:

 

[turblio]

Yea, tbh it all sounds equal in the long run, its all about attention to detail I suppose

 

[PaulB]

totally agree with the above!! One day when I have my own r/r I'll invite all those who are interested in their own mapping to come and have a go if they wish. God knows when that will be though!

Il hold you to that one mind !!

 

[Odin]

My own feeling about mapping is that it is best to do the basics on the rolling road, But you can't mimic the real road conditions on a rolling road, Its hard to explain but I can feel through the throttle pedal that the map isn't perfect in some places and if you have someone sitting next to you with a lap top you can explain just how it feels, And they can then make adjustments as you drive which you can feel.

This is how power station did such a good job when they fitted my motec, He said take it away a see what you think, And let him know if their was anything I didn't feel was right, The hardest part to get right in my opinion is the part throttle mapping, Which we sorted out on the road. Kieron you may not agree but this is my opinion gained from the last 5 years of having my motec mapped and re mapped with varying degree's of success.

So though I don't 100% agree with Franks reasoning I do agree that you can't truly mimic road conditions on the rollers, And a degree of real time road mapping is needed to get a perfect all conditions map, Which is something a drag only car wouldn't really need as it spends all its time at full load.


Rob