This page describes an adjustment tool in the ECMLink application that helps to dial in your speed density (SD) VE table based on combined fueltrim data. If you do not plan to run speed density mode with your car, then this page is completely useless to you and you should ignore it.

The SD VE Adjust (CombinedFT) tool maps out and averages CombinedFT over a range of closed loop driving conditions to produce a set of adjustments to the current SD VE table. It's basically letting the ECU track how much adjustment it needs under various conditions and then moves that adjustment into the VE table for you.

If you have the option of running on a mass airflow sensor temporarily while dialing in the VE table, then the SD VE Adjust (SDRatio) tool is probably a better choice to begin your dial in procedure with. Use that tool first to get most of the work done for you and then use this tool to fine tune it once you have switched the ECU over to SD mode.

The following assumes that you have already configured your ECU and installed the sensors for speed density operation. If you have not, please read our ECMLink - Speed Density Setup page. In particular, you must have your manifold absolute pressure (MAP) sensor installed and configured in the ECU Inputs tab of the ECMLink application. And you must have the intake air temp sensor installed and connected to the intake air temp input of the ECU.

You absolutely MUST make sure your fuel settings are already appropriate for your injector size, fuel type and base fuel pressure. If there is any deviation here, then the adjustments to the VE table suggested by this function will simply include those fuel corrections as well! This can create a really confusing configuration if you aren't careful. So please review your global fuel and deadtime settings first to make sure they are at least somewhat reasonable for your setup.