I thought I was all set with a tire and wheel package for my 1996 F150, but because of availability issues I'm having to revisit things.
I'm looking at a lot of factors for this, including but not limited to ...
- Price
- Tread Width
- Load Capacity
- Ride / Handling Characteristics
- Weight of the tire
- Weight of the wheel
- LRR
- Aero considerations
- Aesthetics
Everything I'm considering will have a tire diameter of about 29" to keep the speedometer / odometer happy.
I'm considering tire and wheel options that vary from 53 pounds at 15" wheel size to about 61 pounds at 18". Both would be LRR tires.
I'm trying to figure out offset trade-offs since some wheels (mostly 15") have a negative offset of -19mm to a positive offset of 20mm for 18" wheels. It's my understanding that negative offsets push the outer side of the tire to the outside of the wheel well and positive offsets pull things back under the wheel well.
Of course the 15" wheels are 15x8" and the 18" wheels are 18x9" so there's a width difference of an inch right there. At the extremes you looking at a range of 39mm, or 1.54 inches.
I think having less of the tire out in the airflow would create less drag, but I wonder how that compares to up to 7-8 pounds per corner as a result of upsizing?
I know that more weight is bad because of that whole moment of inertia thing, but I wonder how much difference it makes in terms of energy required to keep a tire rolling versus how much it costs to start and stop a heavier wheel and tire?
Here I am comparing the difference between different sizes of different LRR tires. If the differences are very small no matter what you do (.1 mpg) then that argues in favor of buying what's cheap or pretty or has the best ride or any one of a number of other factors. If it could be .5 mpg or more, well that's something else.
Thanks in advance for your thoughts.