1999 Chevy Metro 1.0L 5spd ecomodding thread

[Daox]

First trip to work with the synchromesh in the trans. It seems to shift a bit nicer, although it wasn't real cold. It acts a bit more like its all warmed up right off the bat which is nice.

MPG was pretty good at 60 mpg. It could have been a lot better but I was tailgated by a few people the entire way to work. Temp was ~40F.

[Daox]

Last night was a quick, dirty, and temporary mod night.

I've been focusing on learning to drive the Metro since I did the P&G vs just driving calculation. It showed me that optimal MAP is 4 psi (10.5 MAP on the SG). So, I've been trying to drive quite close to that. However, I was disappointed in the SG when trying to achieve this. It updated too slowly, and it also jumped around a lot (likely due to the 3 cylinders). I couldn't seem to just stick it at 10.5 very well. It would jump up to 11.3, then 9.8, then 10.7, and so on. So, I figured an analog vacuum gauge would be the way to go. I was SO right. I've only driven with the gauge once, but I LOVE it so far. I'll be looking for something a bit more permanent.

I started out with what I had kicking around. Its just a cheapo vacuum gauge for diagnosing engine issues. I must say it is nice to have a big gauge. It makes for better accuracy.





Next, I found the MAP sensor and used the included tee and some extra rubber hose to tap into the manifold pressure.





For now, I just ran the rubber line over the engine bay, under the front fender, and through the door.





To mount the gauge, I used some wire and hooked it into one of the vents. Its ugly, but it works, and its only temporary.





Using this gauge, I was able to get 71.9 mpg on the SG in to work this morning! It was 40F out. I did ecodrive pretty aggressively though.

I noticed that once I added the gauge, the SG readings seemed to smooth out a little. I'm not sure if this is due to the extra length of tubing acting as a filter/buffer/accumulator, or if I was just able to keep the pedal that much closer to optimal vacuum with the more instant feedback.

As mentioned, I REALLY like this gauge. With the smaller engined Metro, its very easy to find yourself cruising above optimal engine load. This gauge gives me instant and smooth feedback, and allows me to avoid P&Ging when unnecessary.

In other news, I also installed a quick and dirty voltmeter. I found my SG voltage reading is up to .5V off (reads low)! I've seen it off a little, but this is very far off. I'm wondering if I have a grounding problem? The battery still isn't being charged as much as it should though with the P&G I do. I'll eventually have to swap in a deep cycle.

[Sven7]

That's a slick little mod. Maybe a good'n to try until I can get someone (someone, anyone, please!) to make me an MPGuino.

[Chrysler kid]

Great work! Vacuum definitely helps give you a reading on air volume and throttle input. Get working on a grill block to increase the under hood temps and you'll get even better

[MetroMPG]

^ Good luck with that suggestion! I've been bugging him about making a block since he got the car. With that thing's gaping maw, talk about leaving money on the table!

[Daox]

Haha, its coming! Yeah, I know it'll really help too. Its kinda next on the list...

[Daox]

Another great commute in for the temperature. It was only 19F out this morning. Yet, I managed a hair under 62 mpg on the way in today. I'm loving that vacuum gauge!

So, I'm planning on finding a permanent 2-1/6" gauge to mount in the car. I think I can tuck it in the corner of the instrument cluster. I'll have to remove the bezel and carve out an opening for it and figure out a way to mount it there. The picture below shows a spray can cap that is a bit larger in diameter (~2.5") than the gauge, but it gives a good approximation otherwise.





I have a few choices picked out. I'd like something that relatively matches the OEM gauges (black background, white text, red/orange needle). I'd also like a 270° sweep gauge, not a 90° gauge. This really helps with accuracy. There are two VDO gauges that will give me this. If anyone has any other suggestions, I'm all ears.







There is also this Autometer gauge that I kind of like too. It just doesn't have the red/orange needle.

[MetroMPG]

Because you're going to lose points at the next Concours d'Elegance if the needle colours don't match!

[Daox]

Haha, I know it sounds picky. But, if I'm going to be staring at it every day I'd like it to look okay. That being said, if I found a $5 gauge that fit, I'd probably go for it. But, if I'm going to spend ~$35 on a new gauge, I might as well get the one I want.

Another thing I did last night was put the battery on a charger. It topped off last night and removed the charger. This morning it was still holding a nice 12.7V according to the voltmeter. So, it looks like the deep cycle replacement is on hold for now.

[dirtydave]

I really need to get a vacuum gauge.