Recommended offset for after market 17" wheels?

The OE 17" wheel on the V (Five) is 50mm but due to certain wheel designs some 50mm wheels will not fit nor will some 48mm wheels. I would try nothing higher than 48mm. 45mm would be good if you want to play it safe. The Prius Plus forged wheels are 42mm or 43mm and the Lexus CT200h wheels are 45mm.

If you want to reduce the mpg hit from 17s as much as possible stick with a 45mm-48mm wheel and choose a very fuel efficient tire.

I assume you mean a 2010 model Prius because they stopped using Roman numerals for 2011-2013.

 

No worries. I figured as much after looking at your old car.

Life would be so much better if they made the Energy Saver A/S in a 215/45/17. They don't, however.

The two most efficient tires I know of in the size we need is the Ecopia EP422 and the PureContact with EcoPlus. The MXM4 is a fantastic tire but not the best for fuel economy. If you want a quiet comfortable ride the EP422 and MXM4 are great,the former is best for economy but sucks for handling and the later does everything very well except economy. LOL

The Bridgestone Serenity Plus is a good alternative because it does most things well, has long tread life and it is inexpensive which makes up for some of the mpg loss. If you can get the $80 rebate on the Goodyear ComfortTread tires that could work well.

 

The correct size would be a 205/50/17. That size looks better on a non-lowered Prius anyway because of the taller sidewall. Unfortunately that size makes it an Extra Load tire so it rides pretty rough. That I why I got rid of them. They handled well though.

 

If you are not looking for awesome handling then yes, the Ecopia EP422 in a 205/50/17 would be the way to go if you are not lowering the car. It's sort of a mushy tire but aired up to 40+psi they handle well enough for me. Fuel economy seems better than the other tires I've tried in a 17" size and they are not too harsh. Try to get the $70 rebate from Costco or other retailer. Otherwise the Goodyear ComforTread in the same size could be a good option since they have an $80 rebate at Discount Tire and it is not an XL rated tire so it may be more comfortable and quieter. The difference in tire size is not huge between the 205/50/17 and the 215/45/17 but it is noticeable and since there is no tire that stands out in terms of mpg in the 215/45/17 I decided to go with what looks nicer by reducing wheel well gap. Plus now my speedo reads correctly though my Odometer reads slower. I don't mind that though.

I think the lug nuts from the OE 15s will fit the Plus wheels. I'm using the OE lug nuts from my Prius on my Lexus wheels.