From what I know, the purpose of a spoiler is to push the car down for better traction. This increases the downward force and the car has to compensate for the increased friction from the downward force by applying more power and this has to result in reduced MPG. It is quite difficult to reduce aerodynamic drag by retrofitting a spoiler on a car that has been properly designed to begin with. When a car manufacturer adds a spoiler after the fact, they are admitting that the design without the spoiler was defective! (something I find hard to believe from a Toyota designed vehicle)<br><br>I am fairly certain that the Toyota cheif engineer liked the "sporty" look of the spoiler and made up a story about increased MPG to shut up Priusman. The fact that Toyota is actively pursuing car racing and enticing race car drivers away from Honda makes me believe that the spoiler is there just for looks and MPG be damned. <br><br>Was there not a posting in this group about a Toyota executive getting upset that a customer had removed a spoiler and therefore ruining the "look" of the car. The sporty look ties in with the lack of cruise control.

I'm eager to spend time driving in a Prius so I can tell more, but isn't the real reason for the spoiler to make it harder for the cop behind you to read your speedo display?!<br><br>;-)<br><br>Eric, getting punchy at P minus 23 days

I did some checking on the readability of the speedo from outside the car. Driving in the SUV, my wife could not read the speedo from behind the vehicle. While driving in my old truck next to the new car, it was easy to read the speedo from both sides of the car and as far as 3 lanes over. I could see the computer screen well enough to see what kind of milage she had been getting by looking at the bar height in the history screen.<br><br>Beware of any cops driving to either side. Your speedo is your enemy. No playing dumb here.

Spoilers do other things than just provide negative lift. I learned this from a rocket scientist/professional motorcycle racer friend of mine. (Yes, that is a frightening combination, BTW). I was remarking about what I thought was a dumb looking little spoiler on the back of a motorcyle. My friend explained that its purpose was to clean up the air flow around the back of the bike and rider, and that it worked very well. Apparently it extends the effective (from the air's point of view) structure of the motorcycle.<br><br>From what Priusman and his engineers say, I imagine that the intended function of the spoiler is cleaning up air flow, not negative lift.<br><br>I'm also in the "I like the looks of the car with the spoiler" camp.<br><br>Michael Stirrat

hbprius said: Beware of any cops driving to either side. Your speedo is your enemy. No playing dumb here. <br><br>SML say: just switch it to KPH

&lt;&lt;&lt; hbprius said: Beware of any cops driving to either side. Your speedo is your enemy. No playing dumb here. <br><br>SML say: just switch it to KPH &gt;&gt;&gt; <br><br>If your running lights or headlights are on, you can also use the dimmer switch/dial to lower the light level on the speedo way down or even off! The dimmer is to the left of the steering column, right next to the outside mirror adjuster switch. So when entering known speed traps . . . .

I talked to a guy today about the spoiler, he ended up talking me into removing it and adding a bigger one, we are going to add a 3 foot deal with built in break light, he is also lowering the shocks so the car will sit on the ground, he is going to paint the hood a Red color with a nice gradient fade to a bright Orange, I am blacking out the headlights and taillights and I am exchanging the Toyota wheels for some gold Daytons. I am hooking 2 14 inch subwoofers and a 300watt amp directly to the large battery behind the seat.<br><br>with the final change being a momo stearing wheel I think my Prius will be the coolest on the block<br><br>SML

I presume you'll also be taking out the hybrid system and dropping in a Hummer engine...

NO, that is not cool

What's with the red to orange fade on the hood? You need LIGHTNING BOLTS, man!!!!! Big fat yellow lightning bolts on a black background. Then it'd be cool!!!<br><br>Also, be sure to cover those grilles in the rear deck with toy dogs that bob their heads! <br><br>Robert Snyder

Orange, no headlights or taillights, sits on the ground ... you're turning it into a pumpkin!

&gt; sml2030 said:<br>&lt;snip&gt;<br>&gt; a momo stearing wheel I think my Prius will be <br>&gt; the coolest on the block<br>ROTF-LOL!!!<br>Want to play the "Jetsons" car sound thru that killer sound system? :-)<br><br>Bill Powell<br>(playing with sound samples...)

I like the lightning bolt idea. In the old days we would have put nitrous on it but this is the year 2000 and I think an extra set of Nicads is the perfect performance enhancer.

I think this is a response to my posting; I discussed "cleaning up the airflow" which is just another way of saying that the intent is to reduce drag. If so, it should increase milage, or, conversely, when removed milage should decrease.<br><br>I tried it. Milage didn't decrease, if anything it increased slightly. I do aerodynamics and am prepared to discuss the absurd design of the spoiler, but the experiment speaks even more loudly than theory.<br><br>Besides, a Toyota executive has stated that it was put there purely for marketing reasons.

Yes, there was such a posting. I'm the person to whom it happened. Also, I posted a calculation that shows that the spoiler is too small to create a useful downward force. Besides, the cross-section shape is wrong if that were the intended purpose.

Please post pictures of your wildly modified Prius when you're done! Thanks,<br>Eric in Enfield