Get Wheel Fitment Right — Or Pay for It Later
Buying custom wheels for your vehicle is more than just picking a good-looking design. If the wheels don’t fit right, they don’t work. Misunderstanding key fitment specs like PCD, offset, width, or center bore can lead to vibration, rubbing, or even dangerous handling. Whether you’re a professional tuning shop in Europe or an aftermarket wholesaler sourcing from Asia, knowing these specs is non-negotiable.
This guide breaks it all down in simple terms — so you can avoid costly mistakes and choose wheels that fit perfectly, every time.
1. PCD (Pitch Circle Diameter)
What it is:
PCD stands for Pitch Circle Diameter. It defines how many bolt holes a wheel has and how far apart they are.
How it’s written:
It’s usually written like this: 5×114.3
- The first number (5) = number of lug holes
- The second number (114.3) = diameter (in mm) of the circle that passes through the center of each hole
Why it matters:
If the PCD doesn’t match your vehicle’s hub, the wheel won’t mount — period. Even a 1mm mismatch is a dealbreaker.
✅ Pro Tip: Google your car’s year/make/model + “bolt pattern” to quickly find the correct PCD.
2. Offset (ET)
What it is:
Offset is the distance (in millimeters) between the wheel’s mounting face and its centerline. It determines how far in or out the wheel sits on your vehicle.
3 Types of Offset:
- Positive Offset (+ET): Wheel sits further inside the fender. Common for FWD and newer vehicles.
- Negative Offset (-ET): Wheel sits more outside (concave look). Often used for wide-body kits or off-road builds.
- Zero Offset (ET0): Mounting face is exactly centered in the wheel.
Why it matters:
Incorrect offset can cause tire rub, poor handling, or clearance issues with brakes and suspension.
🔧 Rule of Thumb: More positive = tucked in; more negative = pokes out.
3. Wheel Width & Diameter
What it is:
- Diameter = Size of the wheel across the center (e.g., 18 inches)
- Width = Distance between inner lips of the wheel (e.g., 9J = 9 inches wide)
Why it matters:
Wheel width affects how the tire sits — stretched, flush, or ballooned. Width and offset together determine stance and clearance.
📏 Example: “18×9.5J ET35”
- 18-inch diameter
- 9.5-inch width
- +35mm offset
💡 Note: Wider wheels = better grip, but only if properly matched to tire width and fender space.
4. Center Bore (Hub Bore)
What it is:
The center bore is the hole in the middle of the wheel that fits over your vehicle’s hub.
Why it matters:
If the center bore is too small, the wheel won’t fit.
If it’s too big, the wheel can fit — but it needs hub centric rings to prevent vibration.
🎯 Always aim for hub-centric fitment. It ensures the wheel is centered correctly and reduces stress on the lug bolts.
Why All This Matters in B2B Purchasing
For automotive businesses, understanding these terms helps reduce:
- Returns & remakes
- Customer complaints
- Installation delays
- Safety and legal risks
Whether you’re importing forged wheels for European sports cars or off-road builds in Australia, knowing the fitment basics avoids guesswork and builds trust with your end customers.
Final Thoughts & Next Steps
At FLEXIFORGED, we work exclusively with B2B clients worldwide who require precision and consistency. All our custom forged wheels are manufactured with exact PCD, offset, hub bore, and width specifications to meet your vehicle’s demands — and your customer’s expectations.
✅ Need help with custom wheel fitment?
Email Jackie Wei at jackie.wei@flexiforged.com
Or visit our website: https://flexiforgewheel.com/
Choose fitment that fits your business.
Custom forged wheels — done right, from the start.