Quote:
Originally Posted by COcyclist
Welcome RAV4. I believe your are using the template correctly. It can be impractical for normal road going vehicles. Despite all the other mods that I have done to the Golf TDi this one is still in the dreaming stage. Most of the ones you will see on this site are done on pickups or small vehicles that already have half of the boat tail built into the car, like the gen 1 Insight. How much of your driving is highway/high speed? You may see zero benefit in town driving or even lose mpg-e due to increased weight. Many users report better handling at high speeds with a boat tail or Kamm cover. If you search for "phantom boat tail" you should find some data Phil has provided about the benefit of an 80% boat tail having nearly the same Cd as a full length one.
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Truth be told I probably do less than 50% high way driving. I was thinking of making the boat tail from card board or something light that will hopefully not weigh much. I also thought benefits from a boat tail could be had at around 30mph + ? That is still within city driving speeds. I generally see 35 to 40s.
Quote:
Originally Posted by freebeard
Yes. It's a common mistake. Here's an example:
Same as yours, but it also ignores the cross section. The template cross section is a half circle, your RAV4 is not (does it have the Tesla drivetrain?)
Here is a 3D version on the Beetle:
The 'rudder' is at 4ft (from stock length) to accommodate a reflex curve. The solid former is at three feet, for a 45° gathering angle. The hollow former is at the location of a stock rear bumper. All shorter than the Template.
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Hi Freebeard,
The rav4 ev does have a tesla power train unfortunately Toyota did a pretty poor job at adapting the power train to the rav4 ev. I don't think it even receive the same sway bar as the rav4 sport! It is FWD do it loses traction very quickly unfortunately, and you can only charge it from a lv2 charger so no CHAdeMO or CCS combo and definitely no super charger. Cruise Control sometiems crashes if you turn it on too fast @ speed. Other than that its a great car. Sits too high though and so has a high roll over risk, but if you look up the RAV4 EV that ran the pikes peak challenge it was lowered and looked great!
I will try again to see if I can fix the lining of the template and vehicle. It really is a challenge now that I notice how flat the roof line is. In fact, after some tries it almost seems like the kam on the back isn't helping? That and almost like I have to chop the top rear end of the rav4 ev. Of course the other option is just to have a ridiciously long boat tail. It seems that with a boat tail you can't go wrong with long!
Quote:
Originally Posted by basjoos
Since the back end of the car is most important for aero, you need to pull the template forward so the top and bottom of the back end of the template matches the top and bottom of the back of your vehicle. You don't need to be concerned that the front end of the template is sitting at the front of your hood. In your example above the bottom of the template is well below the bottom of your RAV4. Pull the template forward and you will get a much more manageable boattail. The trick will be melding the fairly straight rear roofline of your vehicle with the curve of the template.
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Still not sure if it is right. I didn't try to move the template on to the hood since it made the tail too short. Unless I am approaching this completely wrong!sorry