Reading many threads on debating likes of turbo sizes ecu hardware software this then that all means shit to me For argument sake going to refer to a normally aspirated engine in standard trim. All i understand from reading from here the whole point to mapping is to make more power aight but how? How would you even begin mappng a standard car after u hook up everything like??

 

"Mapping" is just making sure the ignition is advanced as far as is safe, and the fuelling is doing what you want (so for an N/A car about 12:1 flat out)

 

I seen various screen prints of what looks like series of tables and a green mountain next to it? I guess this is where you would change the ignition and fuel figures but what do all the figures means? Fair enough 12:1 is what a non-turbo car should be, but what about everywhere else like normal driving how does that translate?

 

https://passionford.com/forum/viewto...hlight=mapping

https://passionford.com/forum/viewto...hlight=mapping

 

The best thing you could do is read Stu's live mapping tutorial, but essentially the grid next to the graph is like an excel sheet, up one side is RPM and up the other is either Boost or Throttle position

The values in the grid tell the ECU how much fuel to put in for any set of cricumstances.

So at 6000rpm and 90% throttle, it looks up the values for that, and opens the injector for the amount of time it says in the map.


Get your head round that concept first, and then we can talk some more about other factors that also enter into it that arent clear from that map.

 

Stu's topic is here:

https://passionford.com/forum/viewtopic.php?t=93911

 

Been reading that thread but sort of lost me, just want to learn how you guys go about mapping a road car. I do not care at this stage about ecus hardware software firstly like to get my head around concepts but what are they

 

CLICK HERE FOR FULL SIZE: http://i7.photobucket.com/albums/y25...icp-rp-005.png


Thats an ignition map.


The ecu looks at sensors on the engine to determine your current RPM and Boost.

It then looks up on that table to find the appropriate value, (if its in between two or 4 cells it takes an average basically)


So at 1 bar of boost (2000mpa) and 5000rpm, it would take the values of 18.25(1751mpa) and 14.25(225amap) and come back with 16.25

So that would be your base timing in degrees

 

Right so how do you get those figures to start off with?

 

Right so how do you get those figures in the tables to start off with? is a base map basically all the tables filled in with default numbers or one which is designed to run a standard car 'out the box'

 

When you buy an ECU, its blank.

You either guess at some figures to get it running, or you beg/borrow/steal them from someone else with the same ecu

Thats just to get you "in the right ballpark" you then do the process of "mapping" to refine them to more suitable values for your car than for audi 20vt or whatever you just stole the numbers for!

 

ooo so its a crafty job then

Looking a your picture you got RPM against Map sites (whats map sites?) sticking with non-turbos how would this work? guess you would use RPM against throttle position or from air flow sensor or manifold pressure (map)?

 

Yes any of those 3 options is fine for an N/A motor.

Airflow meter being the most common on production cars

 

what sort areas would you look at getting a car to idle?

 

To get a car to idle you only need to look at the no load values at the low rpm end of the scale.

but most ECU's have seperate idle strategy's as well not on those maps, on the L8 from RP Labs for example you have a curve of required idle speed versus temp, and you have adjustments for timing based on distance from idle etc.


There isnt just a single box that you enter a value in to get the car to idle, its more complicated than that.

 

Is there something specific you are after knowing, or just "in general"

Ie, Have you just bought a mappable ECU or something?

 

Just in general really the typical way you would go about setting up a standard engine hopefully if i understand the process and concepts then i might understand these books on tuning, gotto start somewere

 

If it has a seperate thing for idle as the temperature goes up you would decrease the fuel values and what about ignition? how does a idle valve play into this? How do you make sure it stable in different conditions like high altitude or middle of artic weather or in the outback of aussie land.

 

Idle valve control tends to be of closed loop operation.
So the further the idle strays from the required value the more the ICV opens to control it.

So if you are somewhere with less pressure (high altitutude) it would automatically compensate for that by being open a bigger percentage of the time.

Ignition as idle speed control is crude but some systems do it.

you basically set an "idle screw" of some sort to allow enough air in to idle on both a cold day or a hot day, and then you set the ignition to control the speed.


The way this works would be something like

500rpm 15 degrees
1000rpm 12 degrees
1500rpm 5 degrees

What this means is that if the revs increase, the ignition is naturally pulled further and further down as the ECU interpolates towards the higher rpm values which are less ignition.

 

AFR baffle me are you ment to target the same ratio for all revs and loads you mentioned 12:1 for non-turbo, other threads for turbos always mention 14.7:1?

 

you use different air fuel ratios for different applications,,,so different points in the map



this may help you

 

So if AFR not constant for all revs and load sites how do you know how rich or lean to make it?

 

The same way an electronics engineer knows what components to use to make a circuit do what he wants i guess? Thats his trade and he has learnt exactly what works and what doesnt.

There are various rules to learn in any trade, AFR being one of them in a tuners.

Excuse my answwer if you actually meant "What AFR do you need for all the different loads" as oposed to what you actualy asked...

 

POTENTIALLY WRONG RULE OF THUMB:

On boost hard = 11.5:1
On boost a little = 12:1
Part throttle economy 15:1



Thats a total ballpark to aim for, but can vary from engine to engine, and you need to do things such as monitor EGT to know whats happening.

 

you need to buy dave walkers book and read it

 

totally agree,,(or we should bully stu to write his book ) it will give you an understanding of what and how ecu's work

http://www.amazon.co.uk/Engine-Manag...e=UTF8&s=books

 

On my shelf for months to be frank i felt a little out of my depth reading that got me fuzzooled the books aimed i felt at people with some basic knowledge and concepts in some sort of order me aint got a banana

 

As you are in london its a shame you werent at the middlesex RSOC meet last month, there was some properly in depth mapping chat going on

 

the only person i got to bounce ideas of is my mother and jade

 

Gareth, well come down to weston one sunday

 

i have promised to pop down one day,,, just dont seem to ever get there

 

That is cause you are a CUNT

 

Not ready for hardcore mapping chat bud you lot would make me look smaller than my manhood