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AFR with strange VE map Table

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I am using an AEM Infinity to tune a 2GR-FE installed in a MR2.

engine is Stock with the following additions:

Turbo kit with BW369 turbocharger top mount

Aftermarket intake manifold

Water to air intercooler.

I have not been to a Dyno but my road tuning is giving a very rapid change in the VE map to meet my desired fuel in the 5000RPM range.

Anyone care to have a look at my based map and log. Any help will be appreciated.

Please note that this last run is asking for even more VE to reach the desired AFR


When someone says a big step in VE is required in one area I like to cover some basics first.

1) Is fuel pressure significantly dropping, increasing, or becoming less stable in that area?

2) Does cam lift or phasing change significantly in that area, or do secondary butterflies or another major item impacting airflow have a change in that area? This can include normal VVT behavior or a VVT issue, like perhaps a cam goes way off target in that area.

There are other considerations, but let's verify if either of these

Hi Mike thanks for the response.

1. Fuel pressure looks fine throughout the rpm range.

2. I am not certain for the Cams. Throughout the rpm range, the Cam angle remains very close to zero.

3. Can having the wrong injector offset bring about such outcomes?

I have attached some files with pics.

Here we go. The encircle values are typical throughout the rpm range.


Also, Have a look at the VE values""

Thank you, that gives a much better idea of the scale of what you're seeing.

Yes inaccurate injector characterization will skew VE values, but it wouldn't manifest in such an extreme step only in that area. It would cause a greater impact in areas where total injector on time is relatively low since the incorrect deadtime is a greater portion of the total on time, and it would skew VE values some in general.

What you're showing is possible on some highly tuned NA engines, but you're very smart to stop and wonder if this is "real" or something is amiss.

Since you aren't currently moving the cams from 0 deg, I suspect your low/mid RPM VE values will get closer to your high values over 5000 RPM once you apply some intake cam advance at low/mid RPM.

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