cg13 and cg10 timing values

[micra_pete]

what you see is what you get, timing in degrees, rpm scale down one side, load across the top

standard ecu's

CG13DE

CG10DE

Difference - cg10 minus cg13

 

[micra_pete]

if anyone is interested, you can happily run a cg10 ecu on the cg13 without any knock, just making that clear if anyone was concerned.

you are however running 8 degrees more at the high end.

if anyone is interested in general the timing maps on all 1.0's are the same, the 1.3's are the same, and most japanese k11 1.3s are also the same (mostly) as uk cars.

the load on the top is a calculated value the ecu uses based on airflow, temperature, and throttle position (sometimes other things too)

 

[Ed]

Very interesting stuff, for those looking at this notice how at maximum torque (RPM) of the engiens there is slightly less ignition advance. Max torque = max (average) cylendar pressure so this is usually the minimum advance of an engine at a hight load point. This becomes critical on turbo cars most pull out too much ignition all the way to the redline but after peak torque you can dial more back in to gain some more top end high rpm power. Also if you experience det the area of max torque is usually where it will happen first.

 

[rlees85]

Ok think of ecu1 is from an engine thats maximum torque output is 2600-2800RPM and ecu2 is from an engine thats maximum torque output is 4000RPM

is you used ecu2 in the car ecu1 came from... that could potentially cause problems couldnt it??

 

[Ian]

ok im no expert here (as we all know ) but if i run a 1.0l ECU on my 1.3 then the timing will be mainly advanced a few degrees. So this could make slight more power with higher octane fuels?

or am i way off the mark here?

 

[Ed]

Not quite, I read that as the torque point on both engines being very similar, but the 1.3 being more defined on the maps.

Ian that would follow yes, a few degrees can make a big difference.

 

[Ian]

ok sounds pretty good then. Suppose it could take a 10th or two of a 1/4 mile run when used with optimax + octane booster?

Guess i gotta go get hold of a 1.0 ECU to try out with a full janspeed

 

[Ed]

You shouldnt need both. But in any case, its quite a marked difference between them. Anyone got the compression ratios of both engiens and cam timings to hand? - im posting from bulgaria at the moment and have access to nothing haha.

 

[Ian]

both engines are the same iirc 9.5:1. pete posted up cam info yesterday.

 

[Alienfish360]

so if I run a CG13 ecu in my CG10 at the higher revs my ignition will be retarded by a few degrees?

 

[Ed]

the CG10 ECU has a more agrssive timing map. you would loose power going to the CG13 ECU.

 

[Ian]

pete. Are the fuel maps of a 1.0l ECU and a 1.3 ECU widly different? Will a 1.3 run leaner on a 1.0l ECU?

 

[mrmaz]

Explaning the high ignition timing values

Hello all,

Was a little puzzled by the top right corners of the tables with timing advance from 241 to 254 degrees!!! Surely this would be trying to fire a spark in the wrong cylinder.... Anyway here an explanation as to why they are these values (or not!)..

I take it these map were read directly from the memory map in the ecu. The numbers are stored in memory as a binary number which are either 0 or 1. Clearly this is not that useful if we want to represent numbers greater than 1!! so the numbers (called bit(s)) are grouped together as 8 bits, know as a byte. Using 8 bits (a byte) we can represent any whole number from 0 to 255. 00000000 to 11111111. For example:

00000000 = 0
00000001 = 1
00000010 = 2
00000011 = 3
00000100 = 4
........
00001000 = 8
........
00010000 = 16
........
00100000 = 32
........
01000000 = 64
........
10000001 = 129
........
11111100 = 252
11111101 = 253
11111110 = 254
11111111 = 255

Note how nothing in the above table is greater than 255!

However, it can be seen that there is no way of representing negative numbers. Will actually there is and its called the "Twos complement notation", I'm not going to explain it here, but http://en.wikipedia.org/wiki/2s_compliment give a desent explanation if your interested. Because we are stuck with 8-bits, the range of number we can represent also changes. Using 2s Complement we can represent numbers from -128 to 127.

Positive number are repreresented in just the same way. Any number equal to or greater that 128 in the above tables are negative! They need to be converted by subtracting 256 from then. So 254 is actually [254-256= -2]

So the top 2 lines for the CG13DE ECU (i.e 600rpm & 800rpm) is

15 15 15 15 10 9 8 4 2 -2 -7 -12 -12 -12 -12 -15
15 15 20 20 13 9 9 4 1 0 0 0 0 0 0 -7

Thats better! Clearly negative number represent timing retard. i.e degrees BTDC.

I'll leave you to do the one for the CG10DE ECU!!

Hope this is useful...Laters