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Power Fc

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Hello there

Can someone explain me please what is the difference between Inj Map and BaseVTO and VT1?

The only thing i can understand is that the inj map is the fuel target?

BaseVto and vt1 is the fuel in ms or duty..

Attached Files

you can choose what is displayed by selecting the drop down menu in the bottom right of the table area.

having never done a VTEC car on power FC I'm guessing that those tables are the fuel tables for when VTEC is operating

So should i set my targets at Inj map and tune the vehicle from there and on adjusting(base vto and vt1) map?

As I said, I've never done a VTEC Power FC so I couldn't say for certain but that sounds about right.

So on a Speed density Power FC (Honda, Mazda, Nissan, etc), here's how it works. The Power FC is pulsewidth based, not VE based. It's basically a mid 90s ECU.

You have the "base" map, and then a multiplier on top of it, which is the INJ map. The "base" map is the basic injection pulsewidth required to achieve lambda=1 (assuming it's tuned correctly). The INJ map is the target equivalence ratio (enrichment of the base map), but in your case you have AFR view selected which is just a difference in arithmetic. Since you have VTEC, you have two different base maps, because there are two different valve lift settings which breathe differently.

In a practical sense usually the easiest thing to do is to go to your Base maps. In the bottom right, change to "base x INJ" view. Then use the "recalc base" option in the menu. What this does is multiply the "Base" value by the "INJ" value for each cell, and then apply a smoothing algorithm on top of it. Recalc the base maps for VT0 and VT1, and then leave the INJ map alone for now. After the injectors are set tune fuel by adjusting the VT0 and VT1 base maps. Leave INJ alone.

The INJ map is the only map that is accessible via the handheld Commander unit. You can make small changes with it, but most of your tuning should be done in VT0 and VT1 maps. Also be mindful of your air temp correction curve because that has a big difference on fuel as well. You also need to have O2 feedback off for this method to work.

Now, you COULD set your targets in your INJ map and adjust your respective basemaps until actual AFR is the same as target AFR. It might not be practical though. It assumes you want the same target AFR for both VTEC and non VTEC operation, in theory at least.

Use the mapwatch feature to help you see what your AFR is in a particular cell.

Hello Raymond herchenroder, After the recalc base the inj map is all 14.7 (graph is flat obv.).

Since i will tune the VTO and VT1 .When i'll be back to set my targets to INJ map my whole fuel will change ?

I though i should first add my targets to INJ map and then go for the base VT0 and VT1 or nothing will happen?

Thanks in advance!

in the event that you don't have the manual

Attached Files

You don't need to use the INJ map at all once you recalc base. INJ map is just a multiplier. If you view "base * iNJ" you will see final calculated pulsewidth.

Cool awesome got it the only thing is that because there isn't any type of 3d map to see how smooth they are.That's why i though tuning with inj map is better :P

Thank you Kester for the manual:)

Thank you Raymond :))

The FC Edit software for the Datalogit can easily copy and paste in and out of Microsoft Excel. So you can make 2D or 3D plots and see how smooth the tables are.

You can also still tune with the INJ map. However, there is only 1 INJ map, and it applies to both VTEC ON and VTEC OFF. So be careful with it.

Awesome ,what's the best chart to use in excel from your experience ? (2-D graph)

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