GreenHybrid - Hybrid Cars - View Single Post

Tim K · #2 (**permalink**) 01-13-2008, 08:10 AM

Most people already remove the cross rails of the roofrack. That is a common one and I think ford's documentation even spells out the MPG "costs". They even give MPG estimates for running headlights, listening to the radio, etc. Based on that info, it makes sense to drive with no radio, during the day so you don't need headlights or dash lights!

I don't think anyone here has gone to the extremes of building a "tail" though I have seen pics elsewhere. As for the engine block, there are several threads about doing so, but not for the sake of aerodynamics. Rather, in the winter, engine/radiator temps determine if and when the vehicle will be able to operate in EV mode. Therefore, cutting down on cold air flowing through the radiators and engine compartment allows the vehicle to warm up faster and stay warm longer especially at highway speeds. The idea of doing this during warm weather seems like a bad idea. I believe the FEH/MMH actually have THREE radiators up front for cooling the engine, for the AC and for the battery AC. Blocking airflow to these during spring and summer surely would have a negative effect (and could reduce the performance and life of your battery) above and beyond any "fuel savings" that might be realized through reduced drag. Furthermore, with the shape of these vehicles (brick on wheels) I don't think blocking the front of the vehicle will improve airflow around the vehicle reducing drag at all.

As for a belly pan, certainly that is a way to reduce drag, but I would think anything custom like that would be so expensive as not to be worth the fuel savings.

Folding mirrors.....well, I'd say smaller more aerodynamic mirrors might be better only because the idea of driving without ANY side mirrors is certainly more dangerous and in most states probably illegal.

One of the best tips (other than basic hybrid driving techniques of course) is to bump up tire pressure. Ford recommends 35psi. The sidewall on the Conti Eco-pluses says 44psi Max. A number of users here run at 40psi. I usually keep them at about 37.5-38psi.