Hello,

are the GD3 stock mags directly compatible with the GE8 or do I have to change tyre size? My GD3 was totaled and I am looking at a GE8 with steelies.

Thank you

 

The tires are shorter on a GD than a GE, so you’d want GE sized tires, but the wheels themselves are no issue.

 

When I looked on tire rack, i thought that the base GE8 fit had exactly the same size and aspect ratio as the GD3 Sport? Isn't it?

 

My 2010 Fit Sport came with 185/55R16 alloys. The base model GE8 came with 175/65R15 steelies. Those are (very nearly) the same diameter and circumference, with the base model tires being narrower. Compare that to whatever you have from your 2007. I like to use https://tiresize.com/comparison/

 

I found a clean GD LX I might buy but here’s the comparison from stock GD sport to base tires. Would it hurt anything to have speedo error? I mean, it’s a needle anyway.

GE to GD comparison.

 

I am not familiar with the Canadian model designations or the tire sizes that come with them, but you can run any wheel and tire combo you can imagine as long as it physically fits your hub bore, lug spacing, and the space available under your fenders. If the wheel fits and the tires aren't rubbing at full suspension compression or when turning you won't hurt anything. At some point you will have "quality of life" impacts: a really tall tire will sap power off the line whereas a short tire will reduce ground clearance and make it more likely you'll rub the front bumper entering/exiting the road or over speed humps. Conversely, a tall tire might give you a slight boost in efficiency at highway speed. A wider tire might improve handling (in dry conditions) but will likely reduce efficiency.

Small differences are just that -- small differences that you probably won't notice. A 1.5 mph error in assumed vs true speed at 60 mph is probably within the allowable error in the speedometer by the manufacturer and is much less than the amount that all drivers (besides slow-poke me) where I live exceed posted speed limits.