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Zulu's Build Thread (Honda CR-Z)

Hi fellow ecomodders !

I have had my CR-Z for almost a year now and it has been a blast so far and I think I have reached somewhat of a plateau in terms of efficiency. I mainly use neutral coasting (engine ON), DFCO and DWL as techniques to boost my mileage and seems to be working since my tank average is sitting at 45-48 MPG consistently.

I am currently working on an arduino-based active grille block. It is somewhat functional but it still requires a few tweaks, especially if I want it to survive through our harsh Winter months.

I am also working on redesigning the front fascia and bumper to clean up the aerodynamics. To do so, I have created foam blocks inserts (same approach as the ones on my Toyota Echo). This project is also far from being completed.

Last, but not least, I want to build some sort of Kammtail extension/cavity box at the rear of the CR-Z since I know the big efficiency gains are there. This is where I need input from you guys/gals. My objective here is to extend the kammtail by a fair amount, maybe 10-15 inches MAX, rear visibility being the key factor. I want this design to make use of the existing, albeit primitive, rear diffuser.

http://i1381.photobucket.com/albums/...psriqaie0e.png

Let me know what you guys think ! I shall post updates on the progress of each mod.

Cheers.
http://ecomodder.com/forum/%3Ca%20hr...22/%3E%3C/a%3E

Excellent news! Subscribed.

I'm so glad you're planning mods for this car too. You did some inspirational work on the Echo.

For the rear of the car, I would say you should ideally get a receiver/hitch mount on which to base your work.

When I made the tail for the Insight, it blocked the lower segment of the two segments on the hatchback, but I didn't miss it as much as I thought I would. On the open road, no problems at all. But it made it somewhat harder when reversing in tight spots. Solution: backup camera.

I like the CR-Z for all the progressive tumblehome.

What do you propose to do with the taillights?

Subscribed! I love the CRZ and their potential.

I'm now impatiently waiting to see the goodness that is to come :D

I think you should perform coast-down testing like I did in my Escort to get a baseline. Then as you add mods, you can see their effects, both positive and negative :thumbup:

This should be good. Looking forward to updates. :)

Quote:

Originally Posted by CigaR007 (Post 492497)

I have had my CR-Z for almost a year now and it has been a blast so far and I think I have reached somewhat of a plateau in terms of efficiency. I mainly use neutral coasting (engine ON), DFCO and DWL as techniques to boost my mileage and seems to be working since my tank average is sitting at 45-48 MPG consistently.

It's kinda surprising to me that the CR-Z has some low mileage figures compared to other hybrids. Its platform seems very good for an efficiency-oriented project, almost as much as the 1st-gen Insight.

--Active Grille Block--

Here are some details on the prototype Active grille bock:

The systems consists of an arduino UNO board, motor shield and a control panel to activate 2 steppers motors, independently. The vane mechanism is a vent miser, as seen in this thread : http://ecomodder.com/forum/showthrea...ore-29966.html

I took apart the vent miser and kept only the core and added a stepper motor for greater control and torque. A servomotor can also be used and it would provide position feedback, which isn't the case with stepper motors.
I wrote a few lines of code for the arduino+motor shield and it works pretty good.

https://www.youtube.com/watch?v=qm0N3cUInhQ

Arduino Code :

PHP Code:


		
			
#include <AFMotor.h>

// Connect one stepper motor with 200 steps per revolution (1.8 degree)

AF_Stepper motor(200, 2);        // to motor port #2 (M3 and M4)
const int  buttonPin = 2;        // the pin that the pushbutton is attached to

int buttonState = 0;             // current state of the button
int lastButtonState = 0;         // previous state of the button

void setup() {

  pinMode(buttonPin, INPUT);     // initialize the button pin as a input
  Serial.begin(9600);            // set up Serial library at 9600 bps
  motor.setSpeed(60);            // 30 rpm   

}

void loop() {

  buttonState = digitalRead(buttonPin);      // read the pushbutton input pin

    if (buttonState != lastButtonState) {    // compare the buttonState to its previous state
    if (buttonState == HIGH) {
      Serial.println("MICROSTEP steps");
      motor.step(50, FORWARD, MICROSTEP);    //CLOSE GRILLE VANE
      delay(500); 
    }
    else {
      Serial.println("MICROSTEP steps");
      motor.step(50, BACKWARD, MICROSTEP);   //OPEN GRILLE VANE
      delay(500); 
    }

    lastButtonState = buttonState; // save the current state as the last state for next time through the loop

  }
}

Below are a few design sketches and the actual arduino code for the grille block.http://i1381.photobucket.com/albums/...psucgik4eo.png

Here is a basic overall diagram of the system (still in design):

http://i1381.photobucket.com/albums/...pssjs4etzk.png

Looks like the wheels protrude beyond the sides of the body.Maybe okay at the front,but shreds the air near the sides nearest the tail.Not so good.
Cleaning up the rocker panel area and rear skirts would almost be a necessity if the Kamm extension were going to have a fighting chance to operate.And that's complicated given the sophisticated bodywork of the CR-Z.
----------------------------------------------------------------------------
As far as the Kamm extension,here are some examples.And you can use the streamlining tool at the top of the forum page to help with the layout
http://i1271.photobucket.com/albums/...titled1_10.jpg
http://i1271.photobucket.com/albums/...ntitled4_5.jpg
http://i1271.photobucket.com/albums/...itled310-1.jpg
http://i1271.photobucket.com/albums/...d2/Scan102.jpg
http://i1271.photobucket.com/albums/...d2/Scan101.jpg
http://i1271.photobucket.com/albums/...d2/Scan2-2.jpg

CigaR007, you have a great looking car. I love the look of the CR-Z.

I even went to a dealership to sit in one. ( Can't afford one of course )
I noticed almost zero visibility from the rear side windows, and the back of the car.

I just had to ask how you have overcome this issue.
It's a shame, because you can't remove your mirrors, or even install smaller ones.

Your grille block mod is genius !

Please post some images of the full car as you mod. It's a great looking design !

Oh and one more thing - while i was at the dealership, I took a peek at the bottom of the car, the wheel spat design, and also noticed that a large portion of that grille is already closed off from the factory.
I'd still block it though. Anything helps.