I am using 225/50-16 Falken Ziex 512's (all season z-rated) installed on hydras. They were left over from my audi so I'm using them up on the volvo.

The tires are decently grippy for all-seasons, but very pudgy and a bit squishy because of the narrow wheel. For my purposes, I'd seriously consider going with a very stiff, grippy 205 for improved response - at least in the front, possibly going with the 225/50 in the back for a little more flex over bumpy turns. Oh I've only noticed a little bit of rubbing in the front during low-speed u-turn situations (almost full lock). Thats dropped on tme springs and bil hd's.

If I was left with no choice but to use the hydras I have now, I would choose the grippiest 205's I could find. Less rubber, less weight, tighter sidewall, better response, marginally smaller footprint on narrow wheels vs. 225. With a wide enough wheel to stretch out that 225 a bit more, then I would go for 225.

In my current application the problem with the pudginess is that the sidewall isn't able to resist rolling over as well as it should since it is already rounded a bit. But hydras are what, 6"? Way narrow for 225's :) Get this, when I bought the car the rear had 255's on the hydras!! Talk about a marshmallow...daammmn.

With either 205 or 225, you will have more torque than traction with the V8 swap.