I have had some discussions with one of the techs at Omex on the possibility of throttle bodies for the GDI engine. It seems that it is technically a very difficult problem as the injection is performed in several microbursts (my words as I don't remember the exact technical terms used). This is required in order to get a good fuel/air mix for efficient combustion, also it is phased so that no fuel is lost before the exhaust valve is closed. There would be few problems getting an engine to run on a test bed and to produce good power figures. To get it to work efficiently across the range, have good fuel economy, and comply with emission regulations is another story and would require a very sophisticated ECU and a complex calibration.

If you want a tuned engine with variable valve timing similar to the GDI it is much easier with external injection. The Ford 1.60, Mazda 2.0 (MZR), and the Ford 2.5 all have this feature.

In hind sight I think I would have changed my engine to a 2.5 VVT with throttle bodies rather than fit them to my existing 2.0 engine.

Last edited by Gambalunga; 23/07/15 04:52 PM.
Peter

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