Two items to update:
1) Sport exhaust upgrade!
(I didn't look to see if the Metro is on its original muffler, as the Firefly was until relateively recently.)
I noticed earlier this winter that the car had quite a nice (to my ear) sound to the exhaust that I didn't remember from last year. An exhaust note that reminded me of old, old engines (like this one Model A in town, and some old 4-cylinder boat motors).
Then I noticed it was getting a bit louder. I had a quick look for leaks and couldn't find one, so I think the baffles inside the muffler itself may be going. Fun!
2) Too light in the back = easy FWD oversteer on snow?
(Flickr photo: Greg Gjerdingen)
I've taken a couple of highway trips (80-90 km/h = 50~55 mph) recently on snow-covered roads, and was SHOCKED at how loose the back of the car is. It'll oversteer at the slightest steering input. I've had the back end start to come around at constant throttle/speed in a gentle sweeping curve.
And it's got snow tires with lots of tread on all 4 corners.
I double-checked tire pressure - normal. I don't believe I have an alignment problem - car tracks true, rolls forever, no unusual tire wear.
At first I thought: maybe my kammback is the problem -- generating lift? But the Firefly had the same aero mods on, and it
never behaved like this. The biggest difference between the two cars is a lot more weight stripped out of the Metro, all of it from behind the front seats. But I'm sure I haven't taken more than 100 lbs out. Is it possible that little weight change on the rear tires can make that much of a difference?
Anybody ever experience this kind of behavior in a FWD car? I'm going to try adding weight in the back next time I head out on snowy roads and see if it helps.