There are a lot of web pages available that you can use to compare your stock tire size against the two you've listed.

Search for "tire size calculator" or something like that.

More importantly, I'm a fan of using OEM wheels (Honda or Acura) because of the correct centerbore size of 64.1mm. Your Gen 3 Odyssey is a 5x120mm bolt circle with a 50mm positive offset. If you want 18" wheels, 2014-2015 Acura RLX 18"x8 seven-spoke wheels are a perfect fit in terms of centerbore, offset and bolt circle. On that note, I don't know if bringing the rim lip that much closer to the suspension will be a problem.

Those 225/50R17's would look really small in your wheel wells. The 235/55R18 would be pretty close in circumference to both the 235/65R16 and 235/60R17 stock sizes.

OF

 

Thanks for the reply and great info!

 

I bought a set of BMW 16 alloy rims to replace my rusted steelies, bolt patern are same as 120x5, but you need to add in hub centric rings to compensate Center bore gap between Honda and BMW, also switch to Conical lug nuts

 

Yes, tire will fit, that is what I have on my 07 235/55 R28 Continental DWS06 Plus, for wheels, search is your friend

 

READ the stickies up to. There is one for DePax. It has links to the original DePax threads. The wheels, bore, offset, tire size all of it has been beaten to death dozens of times over the years.

 

This is mine with BMW 16' 12spoke rim, switched Honda center caps.
I like it and notice my handling is better than riding on steelies!