The 1978 American Motors Pacer came at the end of AMC’s most unconventional compact era, with its wide stance, large glass area, and distinctly late-1970s American character. Buyers looking after one today are often balancing originality, drivability, and the realities of a car that may have seen wheel or suspension changes over time. Tire fitment on the 1978 American Motors Pacer depends on engine and sub-model, with both bias-ply and radial primary sizes used on 14-inch rims. That means the decision is not just size, but also whether to stay with a vintage-style bias-ply setup or use the radial fitment where appropriate. Getting that choice right helps preserve both the Pacer’s look and its intended stance.
Which Tire Size Is Right for The 1978 American Motors Pacer
The 1978 American Motors Pacer uses four primary tire sizes, and the correct one depends on the exact sub-model and engine configuration. All of them mount on 14-inch rims, but the fitment splits between D78-14 or DR78-14 for 6-cylinder models and E78-14 or ER78-14 for 8-cylinder models. Before choosing a tire, confirm whether the car is a Sedan or Wagon and whether it has the 6-cylinder or 8-cylinder setup.
D78-14 is a vintage alphanumeric bias-ply size in which the letter identifies the tire’s size class, the 78 refers to its profile family, and the 14 designates a 14-inch rim. On the 1978 American Motors Pacer, this is a primary bias-ply fitment used on certain 6-cylinder configurations. Bias-ply construction suits buyers who want a traditional tire format that matches the period feel of the car. This size should be chosen only after confirming that the Pacer is one of the covered 6-cylinder sub-models and that the wheel setup still matches the intended fitment.
DR78-14 uses the same vintage alphanumeric sizing language as a bias-ply tire, but the R designates radial construction and the 14 indicates a 14-inch rim. On the 1978 American Motors Pacer, this radial primary fitment is used on certain 6-cylinder Sedan and Wagon applications. Its role is important for owners who want to stay within the original fitment family while selecting radial construction rather than bias-ply. The key step is confirming that the car is one of the 6-cylinder sub-models that use this size before comparing tire choices.
E78-14 is a vintage alphanumeric bias-ply size, with the letter denoting the tire’s size class, the 78 indicating its profile family, and the 14 identifying the 14-inch rim diameter. On the 1978 American Motors Pacer, this is the bias-ply primary fitment for certain 8-cylinder Sedan and Wagon models. Available choices include Coker Classic and STA products, with Wide Whitewall and Blackwall sidewall styles and tire series such as Coker Classic Bias Ply, Traxion, and Transport Highway. This size is the one to evaluate when preserving a period-style bias-ply presentation on an 8-cylinder Pacer.
ER78-14 is an alphanumeric radial size in which the E marks the size class, the R confirms radial construction, the 78 defines the profile family, and the 14 corresponds to a 14-inch rim. On the 1978 American Motors Pacer, this is the radial primary fitment for certain 8-cylinder Sedan and Wagon versions. It matters to buyers who want the correct radial-type primary sizing rather than converting from a bias-ply fitment. Confirming the exact 8-cylinder sub-model and checking the existing wheels remain the important first steps before selecting a tire.
Sub-model fitment on the 1978 American Motors Pacer is straightforward once the engine and body style are confirmed. The main difference is that 6-cylinder models use the D-size fitments, while 8-cylinder models move to the E-size fitments, so choosing the correct tire starts with identifying the exact sub-model.
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1978 American Motors Pacer Sedan 6 Cyl.
The 1978 American Motors Pacer Sedan 6 Cyl. uses the smaller D-series fitment family, with both bias-ply and radial primary options available. That gives the owner a choice between maintaining a vintage-style bias-ply setup or selecting the radial primary size while keeping the correct 14-inch rim format in view.
The 1978 American Motors Pacer Sedan 8 Cyl. uses the E-series fitment family, again with both bias-ply and radial primary sizes. This matters because product selection, sidewall appearance, and available radial-equivalent comparisons center on the larger 8-cylinder tire sizing rather than the D-series options.
The 1978 American Motors Pacer Wagon 6 Cyl. shares the D-series fitment family with the 6-cylinder sedan, using either the bias-ply or radial primary size tied to that setup. Tire selection therefore comes down to confirming the wagon’s 6-cylinder configuration and deciding whether a traditional bias-ply or radial construction better matches its use.
The 1978 American Motors Pacer Wagon 8 Cyl. uses the E-series fitment family and can be matched with either the bias-ply or radial primary size used on 8-cylinder Pacers. For buyers comparing tires, this is the configuration where the available E78-14 product choices and the radial-equivalent discussion become especially relevant.
Bias-Ply to Radial Tire Conversion for the 1978 American Motors Pacer
E78-14 has three radial-equivalent options for the 1978 American Motors Pacer. Those are 185R14 as an 80-series metric radial, P195/75R14 as a P-metric 75-series radial, and P205/70R14 as a P-metric 70-series radial. These alternatives give a progression from a more traditional Euro-metric radial format to lower-profile P-metric options. A recommended rim-width range of 4 to 6 inches applies to this equivalent grouping, and any change should still be checked against wheel compatibility, overall tire dimensions, and clearance at the car.
Modern Radial Equivalents
185R14
Equivalent 80-series Metric Radial (E78-14)
P195/75R14
Equivalent P-metric 75-series Radial (E78-14)
P205/70R14
Equivalent P-metric 70-series Radial (E78-14)
Important Considerations When Replacing Bias Ply With Radial
Compare overall diameter and section width carefully to ensure proper fit.
Verify recommended rim range (4-6 in) and load needs match your vehicle specifications.
Check fender clearance, steering clearance, and stance before installation.
Consider suspension condition and intended road use when choosing equivalents.
Important Fitment Notes
The tire sizes listed on this page assume factory-standard vehicle configuration. The following modifications may affect tire fitment and are not reflected in this guide:
Suspension changes (lowering, lift kits, spring replacements)
Body alterations (fender modifications, custom bodywork)
If your vehicle has been modified from factory specifications, verify tire clearance before purchase.
Best 1978 American Motors Pacer Tires for Sale
Available E78-14 tires for the 1978 American Motors Pacer include Coker Classic and STA offerings in bias-ply construction. The product mix gives buyers a choice between Wide Whitewall and Blackwall styling, along with series such as Coker Classic Bias Ply, Traxion, and Transport Highway.
These FAQs focus on the exact tire sizes used on the 1978 American Motors Pacer, how fitment changes between 6-cylinder and 8-cylinder sub-models, and what to review when comparing bias-ply, radial, and radial-equivalent options.
Tire Size & Fitment
What tire size fits a 1978 American Motors Pacer?
The 1978 American Motors Pacer uses D78-14, DR78-14, E78-14, and ER78-14, depending on the exact sub-model. All of these are 14-inch tire sizes, with D78-14 and DR78-14 used on 6-cylinder Sedan and Wagon models, while E78-14 and ER78-14 are used on 8-cylinder Sedan and Wagon models.
That means the first step is identifying whether the car is a Sedan or Wagon and whether it has the 6-cylinder or 8-cylinder configuration. Once that is confirmed, the next decision is whether the car should stay with its primary bias-ply size or use its primary radial size, while also checking that the wheels on the car still match the intended fitment.
What size rim does a 1978 American Motors Pacer use?
The tire sizes used on the 1978 American Motors Pacer all mount on a 14-inch rim. That applies across the D78-14, DR78-14, E78-14, and ER78-14 fitments, so rim diameter stays consistent even though tire size and construction vary by sub-model.
Rim diameter is only part of the fitment picture, especially on a collector-era car that may no longer have its original wheels. It is still smart to verify the wheel width and the actual tire size currently on the car before ordering, particularly if the Pacer has aftermarket wheels, suspension changes, or a long service history with mixed replacement parts.
Why does the 1978 American Motors Pacer have more than one tire size?
The 1978 American Motors Pacer has more than one tire size because fitment changes by engine configuration and because both bias-ply and radial primary sizes were used. The 6-cylinder Sedan and Wagon use the D-series sizes, while the 8-cylinder Sedan and Wagon use the E-series sizes.
That split matters because a buyer cannot choose by year, make, and model alone on this page. The exact sub-model determines whether the car belongs in the D78-14 or E78-14 family, and the construction choice determines whether the tire should be selected as a bias-ply or radial primary fitment rather than treated as a one-size-fits-all replacement.
Bias-Ply & Radial Options
Is E78-14 a bias-ply or radial tire for the 1978 American Motors Pacer?
E78-14 is a bias-ply tire size for the 1978 American Motors Pacer. The radial primary size in the same fitment family is ER78-14, so the construction difference is reflected directly in the size code rather than being hidden within the same designation.
That distinction matters most on 8-cylinder Pacers, where the buyer may be deciding between a traditional bias-ply presentation and the radial primary fitment for that configuration. The wheel still needs to be the correct 14-inch diameter, and the car’s current wheel width and overall setup should be verified before changing from one construction type to the other.
What radial tire sizes are equivalent to E78-14?
Radial equivalents for E78-14 include 185R14, P195/75R14, and P205/70R14. Those represent an 80-series metric radial, a P-metric 75-series radial, and a P-metric 70-series radial, giving the buyer several ways to compare modern radial sizing to the original E78-14 bias-ply format.
A recommended rim-width range of 4 to 6 inches applies to this equivalent group, which makes wheel confirmation especially important. Equivalent sizing is best treated as an alternative to evaluate carefully, not as automatic interchangeability, so it is worth checking wheel width, overall dimensions, and clearance at the fenders and steering before making the change.
What should I check before converting my 1978 American Motors Pacer from bias-ply to radial tires?
Start by confirming the car’s exact primary size family, since 6-cylinder Pacers use D-series fitments and 8-cylinder Pacers use E-series fitments. On an 8-cylinder car using E78-14, the radial-equivalent options include 185R14, P195/75R14, and P205/70R14, while ER78-14 is the primary radial fitment in that family.
Wheel width, wheel condition, and available clearance should be reviewed before any conversion. It also helps to inspect the suspension and steering components on a low-use Pacer so the tire change is not masking worn parts, and to verify that the chosen radial works with the actual wheels currently installed on the car.
Choosing the Right Tire
What should I consider when choosing a tire for a 1978 American Motors Pacer?
Start with the correct sub-model and size family, since a 6-cylinder Pacer uses D78-14 or DR78-14 and an 8-cylinder Pacer uses E78-14 or ER78-14. From there, the key factors are construction type, correct 14-inch rim fitment, and whether the goal is a traditional bias-ply look or a radial setup within the proper size family.
On E78-14 applications, product differences also matter because available tires vary by brand, sidewall treatment, tire series, and rim-width specification. A buyer choosing for road use, restoration appearance, or a mix of both should compare those details carefully while making sure the wheel dimensions and current vehicle setup support the selected tire.
What sidewall styles are available for 1978 American Motors Pacer tires?
For the available E78-14 products used on certain 1978 American Motors Pacer applications, sidewall styles include Wide Whitewall and Blackwall. That gives the buyer a visible appearance choice within the correct bias-ply size, rather than limiting the decision strictly to construction and brand.
Sidewall style can change the whole character of the car, especially on a late-1970s AMC where whitewall and blackwall presentations create very different period impressions. The important point is to choose the proper tire size first, then select the sidewall treatment that best suits the vehicle’s restoration direction, trim level appearance, and intended road use.
What brands offer tires for the 1978 American Motors Pacer?
The available E78-14 tires for the 1978 American Motors Pacer come from Coker Classic and STA. Within that size, the product mix includes the Coker Classic Bias Ply series as well as STA’s Traxion and Transport Highway lines, all in bias-ply construction.
Brand matters mainly as part of the overall selection process rather than as a ranking exercise. It makes sense to compare the brand together with sidewall style, tire series, rim-width specification, and the kind of look or use the car is being prepared for, especially if the Pacer is an 8-cylinder model using the E-size fitment family.
Restoration & Appearance
Which tire should I choose for a period-style 1978 American Motors Pacer?
A period-style choice starts with using the correct primary size family for the exact 1978 American Motors Pacer sub-model, then deciding whether a bias-ply presentation or a primary radial fitment better matches the car’s intended character. On 8-cylinder applications, E78-14 is the bias-ply size and ER78-14 is the radial size in that same fitment family.
For many restoration-oriented buyers, appearance matters just as much as construction, so sidewall treatment and overall stance should be considered along with size. If exact originality is important, the final brand and sidewall choice should be checked against marque references or period vehicle documentation rather than assumed from size alone.
How does tire construction affect the appearance of a restored 1978 American Motors Pacer?
Tire construction can noticeably influence how a restored 1978 American Motors Pacer presents, even when the rim diameter stays the same. A bias-ply size such as E78-14 gives a more traditional vintage tire format, while radial primary sizes such as ER78-14 or radial-equivalent options move the car toward a more modern tire type visually and functionally.
That difference becomes more noticeable when sidewall style enters the picture, especially on E78-14 products available in Wide Whitewall and Blackwall form. Buyers aiming for a restoration-oriented look should decide early whether the goal is a strong period-style impression or a less traditional presentation shaped by radial construction and different sidewall choices.
Fitment, Maintenance & Road Use
Can modifications affect tire fitment on a 1978 American Motors Pacer?
Yes, modifications can affect tire fitment on a 1978 American Motors Pacer even when the nominal tire size is correct. Wheel changes, altered ride height, suspension work, or body modifications can all change how a D78-14, DR78-14, E78-14, or ER78-14 tire sits in the wheel opening and behaves at full steering lock.
That is why the actual wheel diameter and width on the car should be checked before selecting tires, particularly on a Pacer that has passed through several owners. Clearance at the fender, suspension, and steering components deserves a close look as well, since a modified car should never be judged by original fitment assumptions alone.
What should I inspect before driving a 1978 American Motors Pacer on new tires?
Before driving a 1978 American Motors Pacer on new tires, inspect the wheels for correct diameter and sound condition, and make sure the selected tire size matches the exact sub-model. It is also wise to check basic suspension and steering condition so the new tires are being installed on a car that can track and carry them properly.
Air pressure, lug hardware, visible clearance, and early signs of rubbing should be reviewed once the tires are mounted. A short initial drive followed by a recheck can help catch problems such as contact at full lock or uneven stance, which is especially useful on a collector car that may not have been driven regularly.
How should tires on a collector 1978 American Motors Pacer be maintained?
Tires on a collector 1978 American Motors Pacer should be maintained with regular pressure checks, visual inspections, and periodic review of tread and sidewall condition. Even a low-mileage car can develop cracking, flat spotting, bulges, cuts, or slow air loss simply from age, storage conditions, and long periods without use.
Storage habits matter almost as much as driving habits on a collector AMC. Keeping the car away from prolonged sunlight, heat, moisture, and ozone sources helps protect the tires, while occasional inspection of the spare and a quick look at wear patterns can reveal alignment or suspension issues before they become road-use problems.
