Tuning issues with Utec & 650cc RC injectors.
OK so I managed to close everything install the AAM return fuel system, with 650cc RC injectors, connected UTEC for the first time, adjusted idle and out to the road. Then hell broke loose. I attach the modified map.

1. IDLE – CLOSED LOOP FUELING

Overall working OK with MAF rescaling in the order of (-16) to (-12).

The only problem is that the car stalls when put in idle while driving at speeds over 20mph. This does not happen when you rev up the engine with the car stationary.

2. OPEN LOOP FUELING

When we first tested the car with the pre-installed open loop fuel map for the 650cc injectors, it was running very lean with AFRs ranging from 19:1 at 2400 rpm (open loop rpm transition point) to 14:1 at higher rpm with more boost.

The injector pulse widths had to be increased dramatically with values reaching 19-20ms at 6-7psi in order to achieve AFRs of 11.5 to 12.

The fuel pressure regulator is set at 2.8-2.9 bar at idle (RC injectors are specified as 650cc/min at that pressure).

The fact that the RC injectors have significantly different latency times than the stock injectors may have a big effect on this, but unfortunately this is non-adjustable with the current UTEC configuration, or is it?

3. KNOCK CONTROL

During hard shifts, the knock sensor will register knock events and the UTEC will retard timing by the preset parameter value. This timing retard remains active (as far as we can tel from the logger) until the UTEC is reset by switching the car off. As a result we have to use very low max knock retard parameter values, effectively rendering the knock control system useless.

One point we would like to be clarified is what exactly each of the following sets of knock parameters does:
Set 1

Knock Retard Step
Knock Maximum Retard

Set 2

Timing Maps Knock Retard Step
Timing Maps Maximum Knock Retard

 

What is your Map Min/Max Value for Mapping? and at what PSI are you running and Gas Octane? Maybe you are really seeing knock coz your timing is a little high around your Peak TQ and with an A/F of 12. I have my Knock constant at 100 100 75 70 60 60 50 55. By the way Im running at 8psi and at Peak TQ my timing never went above 13 and my A/F is around low 11's, any higher than 11.8 then I start to see knock.

 

1 to 14 PSI. Car is leaning from 7PSI. Injectors are maxing at this boost. I run on 95.
I dont quite understand how is possible to record knock during shifts. It is quite peculiar.

 

I think your Timing is High at around your Peak TQ at that boost level. There is a thread regarding shiftknock somewhere around the Tuning Forum.

 

I have JWT cams. So I believe that settings are OK regarding timing. Thanks

 

Well I have tried to alter the values in "0" column timing for achieving limited knock shift and I have put the delay time from open to close loop fueling, as per the relevant thread instructions. The knock shift is still there. Do U have any additional ideas that can help towards eliminating the phenomenon.

 

What version of the Utec firmware are you running, 2.6 was junk so make sure you have at least 2.8 ...

Also, make sure that your MAP sensor is properly plugged in and reading correctly (your can check this from the dashboard), I had an issue once where the sensor had come unplugged and so the utec was not reading any boost (note: the boost gauge will still read fine).

And finally, get someone to watch the fuel pressor gauge and make sure that it is changing with boost / vacuum, if the fuel pressure is not rising in rate with boost then you will run out of fuelling for sure.

 

The fuel is increasing with boost. I run the 2.8d version of UTEC. The MAP is reading correctly the pressure. I calibrated by using the logger. It works just fine.My problems now have narrowed to following

1) I get regularly shift knocks. I can not understand why is this happening. The recorded knock is at RPM shift change under extreme vacuum.

2) Car is iddling fine. But when I change to neutral, from any gear, engine stalls and shut downs.

I have tried to change the degrees of timing under "0" column but the phenomenon remains.

Does anybody have an idea of the Knock parameters that can be typed in. Is there any possibility to change the settings and make it less sensitive while under no load?

 

pmed also to add, turn the fuel pressure up to around 52 at idle, it works better for us and you will have more injector to play with

 

Everything solved out. Thanks for everything