Instructions to change fuel maps on 14CUX Griffith, Chimaera

[stevesprint]

Adam, I‘ve merged and emailed your logs, we can carry on via email.

Adam and for the benefit of others, if you stop logging all parameters in RoverGauge you'll capture more records per seconds. For example turn off water & fuel temps, voltage, currentFuelMapIndex, target idle & lambda etc.

Enjoy, Weather permitting

[stevesprint]

Josh (Discoveryunlimited)

Thanks for your Bosch & 5AM comparison graph, excellent work & certainly confirms everyone’s thoughts and findings.

I'm sure your little Bosch airflow converter would be very popular if its plug & play and you overcome the issues Mark experienced as it won’t require a remap. We all know 5AMs are now all very old and failing and therefore could be the death of the 14CUX. Bosch 4.6L MAFs are still available new and its replaceable hot film cartridge is also used on some BMWs so hopefully will remain available new for a long time.

Furthermore, we currently can’t properly remap a 3.5, 3.9 & 4L to use the Bosch 4.6L MAF as the AFM scalar can’t be increased enough. This means a 4L with the Bosch 4.6L MAF don't flow enough air to use the bottom few rows of the main fuel table. As a result I really hope you can get your head around the AFM linearization code and workout what the linearization parameters do at prom offsets $1C3 $1C5. Dan once said its very impressive code for a 1980s processor without a maths co-processor. I personally think Motorola wrote the linearization code to help sell their processors to the motor trade, sadly I didn't pay attention enough in my physics lessons to King's law of hot wire & 4th order linearization polynomial equations because I never thought I’d use pure maths & differential equations again.

I’ve personally got excellent results remapping my home made 4.5BV with a Bosch 4.6 MAF by increasing both the AFM scalar (prom offset $483) and the AFM offset (prom offset $1C9). The scalar effectively amplifies the whole of the AFM output curve to hit the bottom row of the fuel table on full load and increasing the offset pulls the active row back up to the top of the fuel table on overrun. Works really well & my Bosch MAF has been 100% reliable but won’t work on a 4L.

Josh, do you know what vehicle uses your EV6 injectors? I’m hoping they are available in the UK.

Good luck with your airflow converter, I don’t mind testing its reliability on my Griff.
Steve
P.S, Good to hear you're using Dan’s assembler code and a GEMS 200 step stepper motor.

[stevesprint]

Paul (TRIUMPHBULLET)

Sorry for the delayed reply, I've been busy in the garage but you're always welcome send me a message to get my attention.

Yes you're right.

The code uses the throttle pot input to detect sudden throttle increases & decreases, the throttle table is used to calculate the amount and duration of the extra burst of fuel required for about a second when suddenly flooring it.

There are 5 throttle tables in TunerPro, 12&3 for non-cat maps and 4&5 for cat maps, here's an example how the throttle table works with your R2832 map2.

98°89°73°46°29°17°6°-4°–11–17 - Top row is temperature in hex but here’s Degs C.

18 21 31 5A 7C 99 B3 CC DD EA - coolant temperature (low hex is hot)
06 08 0C 10 14 1C 26 30 33 33 - Detect Throttle opening sensitivity (Accel clamp)
07 07 07 07 07 00 00 00 00 00 - Detect Throttle Closing Sensitivity (Decel clamp) 
3C 3C 3C 64 96 FF FF FF FF FF – Accel Fuel Multiplier for throttle opening
50 3C 32 1E 19 1E 1E 1E 19 19 - Accel time multiplier for throttle opening   
55 55 55 55 55 1E 1E 1E 1E 1E - Decel time Multiplier for throttle closing

Decel Fuel multiplier is the same at all temperatures & found in each fuel map1-5.


Dan created this table so we can convert hex temperatures to degrees C.

first Hex digit down then second Hex digit across, then see Degs C in the table
     0   1   2   3   4   5   6   7   8   9   A   B   C   D   E   F
 0  130,129,127,126,124,123,121,120,118,117,115,114,112,111,109,108,  0
 1  106,105,104,103,102,101,100, 99, 98, 97, 96, 95, 94, 93, 92, 91,  1
 2   90, 89, 88, 87, 86, 85, 84, 83, 82, 81, 80, 79, 78, 77, 76, 75,  2
 3   74, 73, 72, 71, 70, 70, 69, 68, 67, 66, 65, 64, 63, 63, 62, 61,  3
 4   60, 59, 59, 58, 58, 57, 56, 56, 55, 55, 54, 54, 53, 52, 52, 51,  4
 5   51, 50, 50, 49, 49, 48, 48, 47, 47, 46, 46, 45, 45, 44, 44, 43,  5
 6   43, 42, 42, 41, 41, 40, 40, 39, 39, 38, 38, 37, 37, 36, 36, 35,  6
 7   35, 35, 34, 34, 33, 33, 32, 32, 31, 31, 30, 30, 29, 29, 28, 28,  7
 8   28, 28, 27, 27, 26, 26, 26, 25, 25, 24, 24, 23, 23, 23, 22, 22,  8
 9   22, 21, 21, 20, 20, 19, 19, 18, 18, 17, 17, 16, 16, 15, 15, 14,  9
 A   14, 14, 13, 13, 12, 12, 11, 11, 10, 10,  9,  9,  8,  8,  7,  7,  A
 B    7,  7,  6,  6,  6,  5,  5,  5,  4,  4,  3,  3,  3,  2,  2,  2,  B
 C    2,  1,  1,  0,  0, -1, -1, -2, -2, -3, -3, -4, -4, -5, -5, -6,  C
 D   -6, -6, -7, -7, -8, -8, -8, -9, -9,-10,-10,-11,-11,-11,-12,-12,  D
 E  -12,-13,-13,-14,-14,-15,-15,-16,-16,-17,-17,-18,-18,-19,-19,-20,  E
 F  -20,-20,-21,-21,-22,-22,-22,-23,-23,-23,-24,-24,-24,-25,-25,-25   F
     0   1   2   3   4   5   6   7   8   9   A   B   C   D   E   F

To increase your sudden throttle opening fuelling you need to increase the hex values in the throttle table on the 4th row at the required temperatures, you could also increase the duration by increasing the hex values on the 5th row. The column on the left comes into play when the temperature is between the columns and unfortunately its trial and error, good luck.


I also have a copy of the UK 3.5L version if you want to try it
www.remap-14cux.uk/bins/LR_R2667_3.5_UK_Disc.bin

Which fuel map do you run, non-cats or cat and are you in Australia?

Please let us know if Sardonicus suggestion worked, advancing the ignition timing, would be good to know. If not and your running a non-cat map its worth checking your CO TRIM in RoverGauge is over 1.25volts as you could be running generally too lean below 3,400rpm. If you don’t have RoverGauge you could try increasing you’re CO TRIM by turning the AFM screw clockwise half a turn at a time.

Good luck, its all good fun & let me know if you have any further questions
Steve