ITB fuel & spark map help

[dsyfer]

Hi all,

Looking for some help getting a base map ready for my new setup.

Ford 4.0 I6
EMS6860
Individual 48mm throttle bodies - running sequential
Coil on plug ignition: 2 x 3 coil EMS igniters, BA/BF coils - running sequential
24lb injectors

I will be getting a Bosch LSU4.2 5-wire, wide-band O2 sensor, I can run this straight into the EMS without the LC1 controller I think?? please correct if not right.

So am really looking for advice on getting a map that will get me somewhere in the ballpark and up and running, so I can get it to the dyno.

Any help much appreciated.

[RMS]

Judging by your injector size this is NA correct? If its turbo you are going to want the map sensor hooked up to the ITBs for a vacuum signal. If not, with that size injector you might be able to tune it without the map/vacuum line to the ecu hooked up. The fuel map will be very steep, starting at maybe 30 and going to 255 at the high end.

Normally The ECU looks at intake vacuum and will pull a %age out of each fuel cell by vacuum/pressure (fuel override) This is to make the fuel #s more manageable. Most ITB setups have a bouncy map signal which can make tuning tough. If you dont want to use the map sensor you will need a fuel # at 0% tps around maybe 30-40 i think to get it running and up to 255 at the high end/80-100% tps (if you think you will max the injectors out) if you dont use the map signal for fuel override. If you think you can get a somewhat smooth vacuum signal from the ITBs I would definitely try to keep the map sensor signal in there.

If you can get a clean map signal you can have better fuel # resolution (less of a step between fuel #s using fuel override) and can use TPS with the ford 4 liter engine base map in the software and see if that works. That file is map based, but its fairly linear, so if you pick load source as TPS instead of internal Map in ecu setup it will switch the map to tps and the #s should be close to be able to run it. Then you should be able to get it running with the fuel trim %. Just make sure you save your map so you dont lose settings you did. Take a screenshot or write down your ecu setup if you have that done already and load in the 4 liter map. Make sure the ECU setup screen is right with what you had (if you know its right.) MAKE SURE your TPS is in good shape and calibrated well if you decide on tps based load source, if its off or bad it will throw the whole tune off when you get a good/calibrated one!

If you can get a very clean map signal you can use map sensor as the load source but this is VERY hard to do. This is how i have mine setup (mine is ITB & turbo) but it took forever to get the signal good enough to work well off the map signal. It also has a slight delay i believe because of vacuum line length with how fast ITBs get air in the engine when you snap them open. TPS is a better choice if you are NA.

Also if your cams have some to a lot of overlap your higher vacuum maps wont run at 14.7 a/f. They will need to be at least a little rich to run right. It depends on how much overlap but can be up to 11:1 on some engines with crazy overlap.

The bosch 4 wire wideband sensor is $$$. The LC-1 Is nice because the sensors are cheap if you foul one out (easy to do when you start the fuel map from scratch.) The LC-1 is more accurate, but the 0-1v signal gets thrown off a bit going to the EMS. You can manually calibrate it to be more accurate but its a pita. The bosch is plug it in and go, $$$, and a little less accurate.

[dsyfer]

Cheers for that,

Yes it is NA (for now) I am working on the vacuum rail this weekend, so it will have MAP connected, but I was thinking of using TPS for main source and MAP to pull fuel as you suggested. I guess I need to get it running to see what sort of and how smooth a vacuum I can get out of it.

Thanks again

[dsyfer]

It is running , it has good vacuum, brakes work well, it sits at -50kpa at idle, just going over the first log at the moment.

Thanks for the help