Grill Block on 2000 Chevy Cavalier...
 

I have been hypermiling for about three months now when I finally decided to take it to the next level, and try some grill blocks. The material that I used was a white cardboard box that I believed would match the color of my car (which in the end it did very well). I used duck tape in order to hold all of the cardboard pieces to the car.

https://img244.imageshack.us/img244/7527/img0759ec9.jpg

The toughest part of this project was attaching the cardboard to the hood in order to fill the gap between the hood, and the bumper. I had to tape the cardboard on the underside to the underside of the hood in order to make it work. In the end it all worked out yet i had a little more of a gap at the bottom than I would of liked so I added more to the cardboard hood piece.

https://img244.imageshack.us/img244/2448/img0760xz6.jpg

With the bumper pieces I had to line stips of duck tape together to form a block, and then thread them through the bumper, extend the duct tape so it could have a lip of the card board, and wall la instant grill block. I left the center piece of the bumper clear so some air could pass through to the radiator to prevent massive overheating.

After achieving all of this I decided that it was time to head out for Dodge City Kansas! Yehaw! This trip would take about 70miles, and a round trip of 140 not including intown driving time. I first arrived in Dodge City, and my fuel gadge was still on the Full Needle, and had not moved since I started out on my ride. When all was said, and done I traveled 159 miles, and used what my fuel gauge said was 3/16 of a 15 gallon tank of gas.

https://img169.imageshack.us/img169/1741/img0756mp3.jpg

The only problem with this was I didnt know if topping off the tank hurt my results any or the minimal driving I did before testing.

So these are my estimations....Give me your opinions...
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Total Mileage = 159 Miles

min = 4.5 gals/quarter -> 17.25gals/tank -> 1.125 gals per 1/16th
mid = 4.032gals/quarter (subtracted min, and max to get) ->16.125gal/tank
->1.008 gals per 1/16th
max = 3.75gals/quarter -> 15.00 gals/tank -> .9375 gals per 1/16th
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Total Gas used (2/16, and as the pictures shoes a little less than 1/16th)

min = (1.125 * 2) + 1.025 = 3.275 total gallons used
mid = (1.008 * 2) + .908 = 2.924 total gallons used
max = (.9375 * 2) + .8375 = 2.7125 total gallons used
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MPG

min = 159 / 3.275 = 48.5496 mpg
mid = 159 / 2.924 = 54.37756 mpg
max = 159 / 2.17125 = 58.61751 mpg (Actual 15 Gallon Tank)

Avg Mpg = (48.5496 + 54.37756 +58.61751 ) / 3 = 53.848 mpg

2000 Cavalier Stock Mileage
City (mpg) 23 - 24
Highway (mpg) 29 - 34

So just wondering what your opinions are....


Thanks!

Gas gauges are notorious inaccurate and are not linear. Also since this was all highway and the only mod was the grill block I would not expect the mileage to me much over the EPA value especially it the highway speed way at 65 mph. Welcome to the site let us know how it goes when you fill. Also you might want to delete the duplicate posts. Just use the edit mode on your thread.:)

Any 4 or 5 speed j body is capable of 40mpg stock. Just drive about 55mph.

As for your results I'd have to agree that the gas gauge measurements work only for rough estimates. My actual half tank point is 5/8ths on the gauge.

yea and the guage doesnt factor in the gas that in the filler neck (possibly 2 gallons or more)

but they do make white duct tape FYI :D

lol... ohh well live and learn I guess...

How does the mod look? lol it raind tonight so I think im going to get some sign material and redo it.

...but the mods are [with scottish brogue:] "deadddd sexy." :D

Well even though my numbers are crap I can definitely say that the change aero wise made the car alot more stable in wind, and when coasting in gear. The changes made it feel almost as though I was coasting in neutral while I was in gear, and I couldn't figure out if I was imagining the difference or not. When out of gear in neutral coasting was really good as I could go a tremendous distance drafting someone (more so than before when I had the extra drag). Its just amazing how much difference you can feel, and my car only went up at most 6 degrees from where it usually sits, and on a very hot day my car is usually up 5 degrees from norm so it wasn't that out of norm. On the highway the temp went down to a 1-2degree difference so not much of a difference I was happy about that.

I am not sure how much it helped I would like to think it helped me at least some.:D

After all it took me an hour to do it!

I'm a little late on the reply here, but a search for 'Cavalier' found this thread for me. :-)

I did a grill block and passenger mirror delete on my '96 4-door Cavalier. I not only felt the difference in the butt-o-meter, but I saw a 3-4 mph increase on my nuetral coasts (same hills, same commute, every weekday). So I can attest that you are not just imagining the difference.

I'm eyeballing that opening between the hood and bumper now. I want to block it, but it seems like opening the hood will be a challenge. With your block attached to the hood, did you have any trouble reaching the latch?

Good luck with your hypermiling efforts.

I owned a 1991 Cavalier (hence my screen name) with an older version of the same motor as the 2000 Cavalier base model had. Amazingly, I saw better gas mileage at 80 mph than I did at 60 mph!! 42 mpg vs. 38 mpg Granted, my 91 had a differant body style than the 3rd generation Cavaliers, but it does show the possibility for great gas mileage at typical highway speeds.

s2man,

Some car makers use foam to seal the area between the hood and the lock panel so that may be an alternative.

Pete