48mpg City Geo Metro - Page 2 - Fuel Economy, Hypermiling, EcoModding News and Forum

MadisonMPG · 11-09-2009, 03:49 AM

I got my wording mixed up.

If I get another Geo, I will get the cam gear for this one. If I don't, I won't. I still need the stock cam for the highway.

drew1d · 11-09-2009, 12:46 PM

Let the car warm up for a few minutes, than go. I know it sounds like "waste fuel to save fuel," but you'd be surprised what a difference on older cars it can make. (Not necc'l FE but definitely health of the car.)

Also, I'm not sure about Geo's, but do they have an insulated tube that takes heat from the exhaust to the intake to warm it up? Make sure that isn't disconnected.

Christ · 11-09-2009, 01:10 PM

Quote:

Originally Posted by drew1d

Let the car warm up for a few minutes, than go. I know it sounds like "waste fuel to save fuel," but you'd be surprised what a difference on older cars it can make. (Not necc'l FE but definitely health of the car.)

Also, I'm not sure about Geo's, but do they have an insulated tube that takes heat from the exhaust to the intake to warm it up? Make sure that isn't disconnected.

Care to explain how that's any healthier for the vehicle?

You realize that the general consensus is that extended idling periods are harmful to an engine, right?

Here's what happens - You leave your engine idle while it's cold, and the pressure doesn't build up substantially in the oiling system, thereby making it so that even less of the cold oil can make it through to the bearings and piston ring contact surfaces, causing scoring and extensive wear.

Also, even though you've left your engine warm up, now your drivetrain and tires aren't warmed to the road conditions yet, so they're struggling to keep up with an efficiently running engine, dragging your FE down even more.

You're right when you say it's "wasting fuel", because that's all it is. You're not gaining anything except a few MPG in instant economy, which isn't what we're worried about here. We want numbers from the long haul, so to speak.

Have you read the 100+ Hypermiling Tips yet? Good information in there, could change your mind about wive's tales such as this.

drew1d · 11-09-2009, 04:50 PM

Hey, I just figured, if his car was never getting up to operating temps, waiting a few minutes in the morning would get it there.

99metro · 11-10-2009, 10:20 AM

I'm with Johnny Mullet. Block heater. MUCH more efficient with a head start on a warm engine. Don't idle it, just get in and go. I wouldn't worry so much about aero mods since you are probably driving too slow and your commute too short for the benefits. Mostly you will benefit from driving technique. Coast A LOT. On that short of commute, trying not to exceed 40 mph EVER - as a matter of fact, I'd shoot for under 30 mph.

MetroMPG · 11-10-2009, 12:35 PM

I take it your goal is efficiency itself rather than saving money, since you're considering another car.

Instrumentation! You need an MPGuino.

drew1d · 11-10-2009, 01:39 PM

Quote:

Originally Posted by Christ

Care to explain how that's any healthier for the vehicle?

Have you read the 100+ Hypermiling Tips yet? Good information in there, could change your mind about wive's tales such as this.

Did some reading here and on the net. I guess with Modern Cars with fuel injection, the computer really adjusts the fuel flow as needed. Just don't push it when you first get goin'.

When I had my '84 Camaro Berlinetta, that car needed to be warmed up, but I guess that's more because the carbs and other tuning was all geared toward running temps, rather than cold.

I figured old Metro's where 2barrel carbed, but with further reading it's like a single point fuel injection, then moved to multipoint.

It's funny how much cars have changed.

wyatt · 11-10-2009, 02:09 PM

Quote:

Originally Posted by MetroMPG

I take it your goal is efficiency itself rather than saving money, since you're considering another car.

Instrumentation! You need an MPGuino.

I agree, I thought the "48mpg until the end of the school year" was a budget constraint, not a FE goal. As far as the MPGuino goes, I could help him with that, I will be doing an order soon for more parts (broken LCD on current MPGuino), and getting parts to rebuild it from scratch. If you are interested Madison, I just live up the road...

MadisonMPG · 11-15-2009, 02:51 PM

Quote:

Originally Posted by wyatt

I agree, I thought the "48mpg until the end of the school year" was a budget constraint, not a FE goal. As far as the MPGuino goes, I could help him with that, I will be doing an order soon for more parts (broken LCD on current MPGuino), and getting parts to rebuild it from scratch. If you are interested Madison, I just live up the road...

IS that an offer to make me one? How much?

wyatt · 12-02-2009, 02:21 PM

Quote:

Originally Posted by MadisonMPG

IS that an offer to make me one?

Sorry it took so long to respond, I saw this a long time ago and couldn't at the time.
I am not offering to make you one, I am offering to help you make one. I think it is important for you to know how it works (at least some of the basics) and know how to repair it if you need to... or build a second one if you someday have use for a second. I haven't built mine yet since I am still waiting on the Atmega chips to come in from Fundamental Logic (if I knew how to flash them I would just do it on my own... FL is in Canada and shipping takes forever). Once those come in, I will be looking to order the other components. If you want to look into learning how to flash your own Atmega chip (I didn't order extras), we can order parts ahead of time and get you one built and installed. Cost would be the cost of parts (about $25 or $35, depending on what you are hoping for). I should have all the tools you would need.