How Wide Are Your Pants?

I've gotten questions about the difference between Redpants fitment and Widepants fitment. Here are a few things to help clear up some of it.

You can get pretty much any sizing and fitment that you'd like. I have two pre-set sizes to help make things easier. Redpants fitment is the same width and diameter as OEM: 19x8.5" in front, and 19x9.5" in rear. The offset is more aggressive to bring the rim of the wheel out to the fender so the wheels don't look tucked-in. Widepants fitment looks the same from outside the car, but are wider wheels to accommodate wider tires. The specs of the Widepants wheels is completely different, as the offset is changed to work with the extra width.

When choosing wheels, tires must be taken into consideration. Not all tires are available in all sizes, and tire sizing has to keep the original specs in mind especially where overall diameter is concerned.

The RZ05 wheels on my grey car are Widepants fitment. The RT50 wheels on my red car are Redpants fitment. The fitment looks the same from the outside, but the tires on them are very different. Take a look:

Redpants vs Widepants.jpg

Redpants Fitment

You can see that the sidewalls of the tires on the red car are slightly taller. The overall diameter of those tires is slightly taller than the tires on the grey car. Taller tires affect things in a few ways:

-Slightly taller final gear ratio
The slightly taller gear ratio will give you slightly better fuel economy at the cost of slightly lower acceleration.

-Slightly more ground clearance
The slightly higher ground clearance may be just enough to give you that slight bit of extra height to not scrape the front lip or side sills going over speed bumps, or into parking garages or driveways.

-Slightly less fender gap
The reduced fender gap is because the slightly-taller tires extend further into the wheel well, reducing the space between the tire and the fender.

-Slightly more road comfort
The slightly improved road comfort is a result of the extra sidewall acting as an extra layer of shock absorption. (This is assuming you're using the same type of tire but in a slightly taller size.)

Each of these is a *slight* change - none of them are going to be a massive game changer - but they do add up. Because of that, and the fact that you can swap your tires straight over without needing to spend a bunch of money to buy new ones, and that there are generally more tire options, is the reason I recommend the Redpants fitment to most people. Unless you need the extra grip of a wider tire, or you want to brag about girth *cough* there's no practical reason to get a wider tire. So, I usually suggest Redpants fitment wheels so you can get a better look for your Aston Martin without any of the drawbacks.

Widepants Fitment

On the other end we have Widepants fitment. These are wider than OEM: 19x9.5" in front, and 19x11" in the rear. While factory sizing ranges from 275-295 width for the rear, the Widepants fitment lets you run 305-width rear tires. For an early V8 Vantage, like we have, that means you're getting an extra 30mm of width in the back. The fronts, meanwhile, go from 235 on the early V8 Vantage to 265 - also 30mm wider.

When you pinch your fingers 30mm apart, it doesn't seem like much. But keep in mind that the contact patch of a tire is surprisingly small, and it's the only thing keeping your car connected to the road. That extra 30mm of width equates to around 9% more contact patch for the rears, and about 14% more contact patch for the front. What that means for you is you have a lot more grip at the front to use for turn-in, and a good amount more in rear to keep the back-end in check when you throw the car around.

Using the early V8 Vantage as a baseline, the 265/305 tire setup I recommend for Widepants fitment is slightly shorter overall. This basically takes all the benefits I listed above for the Redpants fitment setup and reverses them.

-Slightly shorter final gear ratio
A shorter gear ratio will give you quicker acceleration, but limit your top speed in each gear.

-Slightly less ground clearance
Having less ground clearance gives you slightly better high-speed aerodynamics.

-Slightly more fender gap
Well, there's no real benefit to this, unless you want to slam your car.

-Slightly less road comfort
Not much benefit here, either.

Again, each of these is slight and none will be a momentous change compared to another tire setup. The benefits you do get are, again, slight. But if you're looking for outright performance, it's worth considering. On track, the differences can and often do matter. So if you're looking for every ounce of performance you can get, and grip is a key factor, then Widepants is the way to go.

Fitment that Fits

If you're on the fence and not sure which to pic, email me at and I'm happy to discuss things with you. Style is entirely subjective - everyone's taste is unique and each car has its own style. But fitment is something that can be sorted out objectively, and I'm happy to help you figure that out.