How to run Ford wheels on a Chevy wheel pattern
"Why would you want to use a Ford wheel on a Chevy?" is more than likely the first question that will come to mind. The reason is, most hot rodders like to think out of the box and will take the best parts from different cars and use these parts in their latest creation.
Anyone who has ever removed the front steering/suspension from an old Pinto or Mustang from the '70s and installed it on a '30 or '40s chassis has come up against this problem. After mounting the front end onto the chassis and setting up the upper and lower A-arms, mounting the spindles and springs, things start to get a little weird. It is known how to mount pre-'82 Camaro calipers to a set of Ford Granada disc brake rotors, which will provide more than sufficient stopping power for a 3000 pound hotrod. If a Ford nine inch rear end is also used, there is no problem.
But hot rodders being what they are, want to try something different. So, the Chevy 10 or 12 bolt rear end goes in along with the TH350 or 400 transmission and SBC 350 engine that they got from that donor Monte Carlo or Nova. Their short sightedness shows up when they go to put a set of matching bolt pattern wheels on the car, only to find out that the bolt patterns (and back spacing/offset) won't allow the wheels to go on the car. Sure, you could put Ford bolt pattern wheels on the front and Chevy wheels on the back and they would work, until someone tried installing the spare tire out of the trunk- which will only fit one of the two different bolt patterns. Hopefully, we're going to be able to show you one or two ways to remedy that problem.
 Identifying wheel bolt patterns
The bolt circle diameter is sometimes referred to as PCD (Pitch Circle Diameter). It may be measured in mm but many people are more familiar with the US inch standard measurement used previously.
To convert mm to inches, a calculator can be used, or simply multiply mm by 0.03937, i.e. 120.65mm x 0.03937 = 4.7499" (rounded to 4 3/4" or 4.75"). For slightly better accuracy (really not needed in this case), divide mm by 25.4.
In everyday language you would say, "My rim has a 5 on 4 3/4" wheel pattern", meaning that the rim has five bolts or studs and an imaginary circle of 4.75" is formed by the lug pattern.
 How to measure wheel patterns
This page will be mostly about the 4 1/2" Ford and the 4 3/4" Chevy bolt circle patterns. The accompanying pictures will illustrate how these bolt circles are measured.
As shown in the image above, the bolt circle is projected through the centerline of the holes or studs. On a FIVE bolt circle, the spacing is measured from the centerline of the top bolt to the base of the arc of the bolt circle at the bottom. Another way to estimate that distance is by taking the distance between the centerline of a bolt hole across to the back side of the hole.
For reference, the image above illustrates how bolt circle measurements are calculated for other bolt patterns.
 Wheel bolt circle measuring tool
Often overlooked is the humble wheel bolt pattern gauge. Of the several different types available, the type that comes with the gauges on a large plastic ring may be cumbersome to use. It comes as a kit and has two separate rings, one is SAE, the other is metric, and the kit is expensive.
An alternative is part number 555-80850 available from Jegs (www.jegs.com) for less than $20.00 (shipping included). The tool works like a typical measuring caliper and measures both SAE and metric 4, 5, 6 and 8 bolt wheels. You place the points in the holes of the rims and read the corresponding chart on the tool. Or, you can place the flat pegs over the tips of the studs and read the supplied chart. The chart stays affixed to the tool, everything is self-contained.
 5 on 4-1/2" (5 on 114.3mm) "Ford" bolt pattern
- AMC Gremlin, Hornet, Pacer, Javelin, Matator, AMX
- AMC - most models (exc. Jeep) '40-'89
- Chrysler/DeSoto - all full size RWD car (exc. Imperial) '37-'89
- Dodge van (to 1985)
- Dodge 1/2 ton pickup (2WD to 1985)
- Dodge - all full size car and pickup '37-'89
- Dart, Demon, Swinger '73-'80
- Ford 1/2 ton van (1960s-era Econoline and 1968-74 E100)
- some F100 c. early 1980s have the 5 x 4.5" bolt pattern
- Ford Granada, Monarch
- Ford - all full size cars '49-'72; '79-'85
- Fairlane '62-'79
- T-Bird '55-'71; '77-'79
- Mustang (5-bolt) '65-'73
- Maverick 5-bolt all
- Mustang SVO '85-'86
- Ranchero '68-'84
- Aerostar, Probe, Bronco II/Ranger to '89
- Honda Accord FWD (mid-90s - present)
- Lexus RWD
- Lincoln - all '70-'72; '80-'89
- Mercury - all full size cars '52-'54; '61-'72; '79-'85
- Cougar '67-'79
- Mopar '73-up "A" body
- Plymouth - all full size cars '37-'89
- Barracuda '70-'74
- Duster, Valiant, Volare '73-'80
- Toyota 2WD pickup (Hilux, Tacoma)
- Toyota Camry '92-present
- Mazda RX-7 (2nd and 3rd gen FC and FD chassis)'89-98
 5 on 4-3/4" (5 on 120.65mm) "Chevy" bolt pattern
- Buick - Regal, Century, Special (most mid-size) '64-'80s
- Chevrolet, all (exc. as noted elsewhere) '49-'89
- Corvette, all
- Corvair '65-'69 5-bolt
- GM compact and midsize
- Oldsmobile - 442, Cutlass, F-85, Toronado
- (most mid-size) '60s-'80s
- Pontiac - GTO, LeMans, Firebird, Grand Prix
- (mid size) '64-'80s
 Bolt Pattern Adapters
Bolt pattern adapters normally fit between the rotor and the wheel. The adapters usually come with pressed in lugs for the new bolt pattern, with a lug length of about 1.5". These can be found on eBay for relatively cheap ($30-50USD per wheel+ shipping) in various materials and thicknesses. Note that you'll need to consider the offset/backspacing of your wheels, and factor in the adapter spacing. Like using non-stock wider wheel rims that have additional negative offset to fit wider tires, when you change how far the wheel centerline is away from the hub, you can (adversely) change the handling of your car. This changes the geometric relationship of the tire's contact patch to the suspension's king pin angle. If the centerline of the wheel rim is too far out, bump steer can become more noticeable and the life of your wheel bearings can be affected. Match the adapter thickness to your wheel backspacing to your intended suspension geometry. The adapters currently on the market range in thickness from 20mm to 3 inches. 5x120 to 5x4.5 adapters on eBay
One thing to consider with really thin adapters (20mm and 1 inch) is that the existing lugs on your hub may be longer than that. If the wheels you are putting on have hollow space in between the lug holes, the existing lugs may protrude into those holes (that's OK). If they don't have space for the old lugs to protrude into, you may have to shorten the lugs by cutting or grinding off the appropriate amount. If your are using thicker adapters, this should not be a problems since the old lugs will be completely covered by the adapter.
Because using bolt pattern adapters compromise wheel rim to hub mounting strength, they may not be legal for use in some forms of automotive racing.
Some aftermarket wheel manufacturers make wheels having what is commonly called a 'unilug patten' which have elongated lug nut slots, requiring no adapter and allowing swapping between many popular bolt patterns.
 Things to consider
 Center bore
The center bore of a wheel is the machined or stamped opening in the wheel that centers the wheel properly on the hub of a vehicle along with the lug nut OD and/or lug and wheel hole taper. Ideally this hole is machined to exactly match the hub or spindle so the wheels are precisely positioned as the lug hardware is torqued down. Keeping the wheel precisely centered on the hub when it is mounted will minimize the chance of vibration. Some wheels are vehicle/model specific and will come from the factory with a bore machined to match that vehicle. Some wheels are designed to fit multiple vehicle models and will use a centering ring system to reduce the bore size to match the hubs of different vehicles. These rings keep the wheel precisely positioned as the lug hardware is torqued down.
The offset of a wheel is the distance from its hub mounting surface to the centerline of the wheel. The offset can be one of three types:
 Zero offset
The hub mounting surface is even with the centerline of the wheel.
 Positive offset
The hub mounting surface is toward the front or outer side of the wheel. Positive offset wheels are generally found
 Negative offset
The hub mounting surface is toward the back or brake side of the wheels centerline. "Deep dish" or "reversed" (as in "chrome reversed") wheels are typically a negative offset.
If the offset of the wheel is not correct for the car, the handling can be adversely affected. When the width of the wheel changes, the offset also changes. If the offset were to stay the same while you added width, the additional width would be split evenly between the inside and outside.