RaulChavez

Hi everyone, few months ago i had taken my car to a tuner to get tune which he had set vtec at 5800.

Since then i have been messing with the tune, and was able to lower vtec to 3800, was able to verify with data-logs and the torque and horsepower increase in the mid range.

The only issue I've been trying to deal with has been the fuel map for the new vtec window. I've done many pulls and data-logs and was able to get a flat curve for the afr, but when i look at the actual fuel map graph I see a lot of valleys / peaks, well more like mountain compared to plots next to each other. Not sure if it should look like this or if Im doing something wrong.

Thanks ahead of time.

Haven't had any engine knocks either.

The car is a 03 with AEM intake, T1R Header with T1R Sparrow Single, TP running AEM V2 ECU using 91 pump gas.

blasphemy101

I'm certainly no expert, but you're showing us the whole (3D) fuel map, but just a small portion of the AFR graph. Anyone looking at this isn't going to have any perspective on what is going on with your AFRs vs. your fuel map.

Are you just tuning WOT? The partial-throttle area looks nice and smooth...

RaulChavez

Yeah WOT is the last thing i need to tune, at least with the fuel map. I got the partial throttle fuel map / afr pretty much where i want them. The AFR graph is for WOT.

06Estukay

Show us a 2d map for the the fuel.

Generally, the load lines will not be linear. It's ok for it to have peaks and dips, as long as the resultant afr is where It needs to be. The engine will require different amounts of fuel at different points depending on the volumetric efficiency at different rpm's (camshafts, cylinder head, intake, header, exhaust setup, etc etc. will all affect this).

You should see that the shape of the fuel curve is similar to your torque curve. As a rule of thumb, give the engine what it's asking for, and not necessarily what you assume it wants. I.e. If your fuel maps have peaks and valleys, but the afr is flat, then that's all you need to worry about.

Here is a local S2000 I've been tuning with KPro. Notice how closely the fuel curve correlates to the torque curve. VTEC point here is at 3500 rpm. Note, the fuel values increase towards fuel cut, to gradually richen up the AFR for safety.

2D High Cam Fuel Map:


Virtual Dyno plot:

yamahaSHO

You'd be fine running the AFR flat without the need to richen the mixture up top. Maybe if you were running a lot of boost, it may be warranted, but a good, moderate boosted tune can still be run flat.

RaulChavez

Cant seem to view the map in 2D on AEM or if its possible. So took a snapshot of the fuel table in raw values.

Heres the virtual dyno plot.

06Estukay

OP, the afr looks good. Don't worry too much about the shape of the 3D map.

wadzii

The aem tuner software tends to rescale the maps and make the peaks and valleys look much more drastic than they really are.

If the measure afr looks good and the car drive smoothly its nothing to worry about.

It is a little odd to see a big swing like that but not totally unusual. Sometimes you can get an odd resonance depending on the parts you have and you'll get an area of the map that needs a ton of fuel.

blasphemy101

Interesting to know. My only tuning experience has been with a turbo car on Megasquirt. Weird that the software automatically rescales the graph...

RaulChavez

i change the fuel prefrence from raw to duty cycle and yeah the peaks and valleys are a ton better looking. The car drives smooth and afr is smooth also so i guess its all good. Got to say i was a bit scared to even change the tune but its not that hard to learn the software, sure im not an expert but its nice to know the basics.