[aarondixon]

There are people here more versed on the technical differences, so I will address the practical differences. The OEM 20" tires and rims on the Passport are Low-Profile, meaning the number of inches between the pavement (road) and the rim are "small".

If you are buying one for city/paved roads driving, there should be no problems at all.

But since Honda touts the Passport as being "off-road capable" these are the complete wrong tire & rim combination. A smaller rim (17' or 18") with a tire that has the same overall diameter, will give you more inches between the dirt (road) and the rim. These added inches are what cushions the off-road ride and allows for better performance on dirt roads.

They also usually have different tire thread patterns for pavement vs dirt.

hope that helps...

 

[aarondixon]

I think you will be fine, with well groomed dirt roads.

I would venture to guess that Honda did some testing and bench-marking of tire and rim combinations prior to the production release.

So, my further guess would be that any tire and rim change away from the OEM set-up could decrease your gas mileage and increase road (tire) noise.