Roocars

I would like to ask the tuning guys on the forum what is the best way to set the injector pulse width in the main fuel table. I was trying this on the road, I use two broad band units, the fast unit and a PLX300M.
I center the curser in the box and increase and decrease the pulse time, as required, to get the desired A/F ratio as close as possible to the one listed in the table. I am trying to attain as little positive or negative adjustment by the broad band in each of the fuel cells. Is there an easier way to do this due to the fact that you can't use the auto adjust utility, as you must be at a fixed load and RPM.

Thanks, Roocars

macsperformance

I can help you with your question but may I first ask why you are running the ECU in Alpha-N mode and not speed density? Just wondering your benefit from that form of management.




Chris Macellaro

RonRed89

Not sure that he mentioned Alpha-N in his message. Seemed to me like he had two wideband sensors (perhaps for comparison) and was adjusting manually (without the "L" key in the base fuel table). That's pretty much the way to go as far as I can tell.

Be sure that you're not getting any additional enrichment from other tables so that your adjustments are reflective only of the base VE table. (aka, let the car get to operating temprature and ensure that you have no CTS or IAT enrichment).

Ron

macsperformance

Yes Ron you are dead on... One of his problems could be his enrichment tables adding fuel when they are not needed or trying to adjust the base fuel table while the engine is still warming up.

Alpha-N mode on a FAST uses a Pulse width table for the base fuel map. I may have misread his post but he said he was adjusting pulse width so I assumed he was running the ECU in Alpha-N mode.While speed density mode uses a Volumetric Efficiency table for its base fuel table.

The other reason I ask is this type of table requires more time to get correct than a VE table out on the street.

To address your question Roocars...
There is an easier way to calibrate a Base Fuel table. You need a good load bearing chassis dyno for your car. With the dyno you can hold the car steady state in the load cell you want and then adjust the cell untill you get your desired results. This is much easier than trying to hold the car in one cell long enough to get it correct on the street.


Chris Macellaro

Roocars

Thanks Ron and Chris
I adjust the system in speed density with the closed loupe turned off and try and set the the pulse width in the table, one box at a time . I do use the second broad band to monitor the the change and compare it to the reading I get from the Fast units broad band . Thay are very close. The fast unit is located in the y pipe and the PLX in the header. I can see the need for a dyno it would make this much easer. At this time I go out and do a data logging a run at a set speed and load,then come back and adjust the injector pulse width on the table and try it again .Is this okay, I run at 13.5 to 14.2 at 70 to 80 KPH with little load this seems okay but dose it need more adjustment. I would like to know what A/F you think I should set the unit for when cruising at all speeds to 100 / 110 KPH at this time it runs at 12.8 to 13.5 with a light load. When I turn the closed loupe on I still get a fair bit of adjustment from the fast unit. Is this normal.
Thanks Brian

macsperformance

Hello Friend...

If you would like... you can send me your most current gct file and your most recent log and I will send you in the right direction.

macsperformance@gmail.com

thank you
Chris Macellaro

Roocars

Thanks Chris
I have sent you a e-mail with the information.

Thanks very much
Brian

macsperformance

I returned your email Brian. Thank you very much for your questions.



Chris Macellaro