[brucepick]

Who - re. tire size change.

Take a step back - you mentioned speedo error. Do you have an error now and the taller tire should correct it? That would be nice.

Some thoughts re the tradeoffs with the larger tire:

It's taller so raises car so aero gets worse.
But remember, .7 inch bigger diam. means the car will be .35 inch higher. Yes, .35 inch raise is not ideal but maybe not as significant as the other gains you'll get.

Tire is heavier:

I think the large weight increase will hurt you. But read on, I think there's hope...
A larger tire will be heavier but if tire is taller and also skinnier I don't think it has to be that much heavier than your stock tire, and maybe not heavier at all.

What I'm getting at is I think the tire(s) you've found are rated for a much higher load capacity and so are built with a lot more beef. Probably pricier too. If you find tires with similar load rating and spec'd for 44 psi they'll likely weigh similar to what you have now. You can still run the 44 psi tires at 50-55. If you want more, maybe go to a tire rated at 52 to 55 psi and I'd think you can run it at 60-65-70 psi without worry, if you can stand the hard ride.

Oops - I just noticed you're driving a Santa Fe. Anyway, do look up the orig spec tire and its load rating. No need to get a tire built to carry 50% more weight than OEM spec unless that's how you load up your vehicle.