1999 Chevy Metro 1.0L 5spd ecomodding thread

[Daox]

Another good commute in today despite some very high winds (we're under advisory for 40mph winds today). It was primarily a cross wind, so not horrible which I was pleasantly surprised by since this is just about the lightest car you can buy, and my rear sway bar still isn't hooked up. I didn't get pushed around much at all.

Anyway, the commute in today showed me 62.5 mpg. There was less traffic than usual and thus I did push it a bit farther with the engine off than I have in past days.

The temperature was 34F, and the coolant temp got up to 174F by the time I got to work, and I didn't really use the heat. A grill block would definitely be a good thing to help with that, especially as it continues to cool off.

Just to put things into perspective, my commute home is never as good as my commute in. My trip into work is mostly downhill allowing for much better coasting. My trips home lately have been in the low 50s. So, my tank will probably average out to mid 50s. However, I haven't even filled up once yet. I'm still running the tank of gas that I got with the car (and there is no trip odometer, so I can't calculate this tank). I'll probably fill up soon though and start logging actual mileage.

[mechman600]

Your commute sounds much like mine.

[MetroMPG]

Yes, grille block! That car has a gaping maw of a grille for such a wee thing.

So, roughly half the fuel usage compared to the Sunfire in the same conditions?

[Daox]

Yeah, I'd imagine the Sunfire would be struggling to maintain even 30mpg at this point (on my trip to work). So I'd say half the fuel consumption of the Sunfire is quite accurate.

Another thing I've noticed with the EOC I've been doing now, I've started to pay attention to my battery voltage. Its sags pretty horribly, around 11.5V with headlights on. So, when I went out to the car this morning I checked it before starting. It was at 12.0V when it should be 12.7V. It still starts fine, but there isn't a whole ton of life left in that battery. This is good and bad news. Obviously bad because I don't really want to buy a new battery. But, its good news in that when I replace it, I will be replacing it with a deep cycle for an eventual alternator delete which should show some decent gains.

[MetroMPG]

Have you put it on a charger to see if it comes up/stays up?

I wonder how much net charging you're doing on your commute, especially with lights on.

[Daox]

Well, truth be told, I actually kind of noticed the low voltage before I started doing EOC. EOC just has made me focus on it. I'm seeing up to 14.0V when driving, so I don't think the alternator is bad. I also had a charger on it a few times while I was working on the car just to keep it topped off (also left the door open one night, so I had to recharge it).

I'm not sure if too much EOC is going to be a problem. In any case, it won't be once I get the deep cycle and alt deleted.

[OG VX]

Originally Posted by Old Mechanic

The lighter the car the lower the sectional density, a term used in ballistics to explain how heavier (longer in bullets of the same diameter) projectiles retain velocity for longer ranges.

Basically you have less mass, with which to store inertia, and with less inertia your aero drag will slow the car down faster. Confirm this by adding passenger weight too see if coasting distances increase.

The cool thing is lowering your aero will lengthen coasting distances more that it would with a heavier car, so your aero is more important. Also less mass means the same bsfc will provide you with quicker acceleration, evidenced by your 44 mpg climbing a hill.

regards
mech

One of the most informative posts I've read here in a while. Thank you.

I figured I had a brake drag on the Civic, but last I checked the rear wheels spun (very) freely. This must be it.

Need to lower the OG VX pronto.

[2000mc]

dont hold out on getting something else in there

i almost commented when i saw the brand of the battery in the pics, but hate to poke at someones new car. ive replaced personal friends walmart batteries with thier free replacement walmart battery, more times than all the customer vehicles (not counting those under bumper to bumper) with ac delco batteries less than 18 months old.

[Daox]

Thanks for the tip. Ive never used walmart batteries. I didnt even notice it was one.

[Chrysler kid]

You will want to replace that battery soon as you are overworking that alternator for long periods of time to try to charge a bad battery. So your alternator is dragging your mileage down because it's always trying to draw 14v to charge instead of 12.5 to maintain