The 1959 Borgward Isabella came from a brief but distinctive chapter in postwar European car design, blending compact proportions with a more upscale feel than many of its contemporaries. That character makes tire choice especially important, because the Isabella’s stance and driving presentation depend heavily on keeping the size and construction in the right vintage range. Fitment spans both bias-ply and radial options on 13-inch rims, with 165R13 or 590-13 used on the Base and TS, and 175R13 or 640-13 used on the SW. Available choices range from traditional wide whitewall bias-ply tires to blackwall radials, so the right selection depends on whether appearance, driving feel, or restoration priorities come first.
Which Tire Size Is Right for The 1959 Borgward Isabella
The 1959 Borgward Isabella uses four primary tire sizes, and the right one depends first on the exact sub-model. All of them fit 13-inch rims, but the Base and TS use one pair of sizes while the SW uses a larger pair. The real decision is confirming the sub-model, then deciding whether to stay with the vintage bias-ply fitment or choose the radial size associated with that version of the car.
165R13 is a Euro-metric radial size in which 165 refers to nominal section width in millimeters, R identifies radial construction, and 13 is the wheel diameter in inches. On the 1959 Borgward Isabella, this radial fitment is used on the Base and TS and gives those cars a period European radial sizing format rather than an older numeric bias-ply designation. Available choices include Michelin and Dunlop blackwall radials in series such as XAS, XAS-FF, and SP Sport Aquajet. It is the size to evaluate when the car is set up for radial tires and the goal is to keep a traditional European look on a 13-inch wheel.
590-13 is a numeric bias-ply size, with 590 representing an approximate 5.90-inch nominal section width and 13 identifying the rim diameter. On the 1959 Borgward Isabella, this bias-ply fitment appears on the Base and TS and suits owners who want a more traditional construction and presentation. The available product in this size is a BFGoodrich Silvertown Classic Bias Ply with a wide whitewall sidewall treatment. This size deserves a closer look when restoration appearance matters and the car still uses wheels matched to vintage bias-ply rim-width requirements.
175R13 is a Euro-metric radial size, with 175 indicating nominal section width in millimeters, R for radial construction, and 13 for the wheel diameter. On the 1959 Borgward Isabella, this size is associated with the SW and serves as the radial counterpart to that wagon’s larger bias-ply fitment range. While product selection is not as broad here as in 165R13, the size remains important because it keeps the SW in the correct radial sizing family on a 13-inch rim. It should be considered only after confirming that the car is in SW configuration and still uses compatible wheel dimensions.
640-13 is a numeric bias-ply size in which 640 refers to an approximate 6.40-inch nominal section width and 13 is the rim diameter. On the 1959 Borgward Isabella, this size is used on the SW and represents the larger vintage bias-ply fitment tied to that sub-model. The available option is a BFGoodrich Silvertown Classic Bias Ply with a wide whitewall, giving the wagon a distinctly traditional sidewall treatment. This is the size to review when the goal is to preserve the SW’s period-style bias-ply appearance while staying within the correct 13-inch wheel family.
Sub-model fitment matters on the 1959 Borgward Isabella because the Base and TS share one tire-size pair, while the SW uses a larger pair. Before choosing a tire, confirm whether the car is a Base, SW, or TS so the size and construction match the vehicle’s configuration.
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1959 Borgward Isabella Base
The 1959 Borgward Isabella Base uses the same two-size pattern as the TS, with one radial option and one bias-ply option on 13-inch rims. That makes the key decision less about trim differences and more about choosing the construction, sidewall presentation, and wheel compatibility that suit the car’s current setup.
The 1959 Borgward Isabella SW uses the larger tire-size pair within the Isabella range, again offering a radial choice and a bias-ply choice on 13-inch rims. Tire selection here should focus on confirming SW fitment first, then deciding between vintage bias-ply appearance and a radial alternative in the proper size family.
The 1959 Borgward Isabella TS shares its tire-fitment pattern with the Base, using the same radial and bias-ply size pair on 13-inch wheels. That consistency helps narrow the decision to construction type, appearance, and wheel dimensions rather than searching across multiple TS-specific tire sizes.
Bias-Ply to Radial Tire Conversion for the 1959 Borgward Isabella
The 1959 Borgward Isabella has radial equivalents for both primary bias-ply sizes. For 590-13, the available alternatives are 165R13 as an 80-series metric radial, P165/75R13 as a 75-series P-metric radial, and P175/70R13 as a 70-series P-metric radial, with a recommended rim-width range of 4 to 5 inches. For 640-13, the options are 175R13, P175/75R13, P185/70R13, and 650R13 as a bias-look radial, with a recommended rim-width range of 4 to 6 inches. Each should be checked against wheel width, overall vehicle setup, and clearance before conversion.
Modern Radial Equivalents
165R13
Equivalent 80-series Metric Radial (590-13)
P165/75R13
Equivalent P-metric 75-series Radial (590-13)
P175/70R13
Equivalent P-metric 70-series Radial (590-13)
175R13
Equivalent 80-series Metric Radial (640-13)
P175/75R13
Equivalent P-metric 75-series Radial (640-13)
P185/70R13
Equivalent P-metric 70-series Radial (640-13)
650R13
Bias-look Radial Equivalent (640-13)
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 1959 Borgward Isabella Tires for Sale
Available 1959 Borgward Isabella tires include Michelin and Dunlop blackwall radials in 165R13, along with BFGoodrich Silvertown Classic Bias Ply wide whitewall options in 590-13 and 640-13. That gives buyers a clear split between European-style radial choices and restoration-oriented bias-ply presentation.
These 1959 Borgward Isabella FAQs focus on the exact tire sizes used by each sub-model, how the radial and bias-ply fitments relate, and what to inspect before choosing tires for restoration or regular road use.
Tire Size & Fitment
What tire size fits a 1959 Borgward Isabella?
The 1959 Borgward Isabella does not use one universal tire size across every version. Base and TS models use 165R13 as the radial fitment or 590-13 as the bias-ply fitment, while the SW uses 175R13 as the radial fitment or 640-13 as the bias-ply fitment. All four sizes are built around a 13-inch rim.
The first step is identifying the exact sub-model, because that determines which size family belongs on the car. After that, the decision shifts to construction and presentation, especially if the car has been restored, modified, or converted from bias-ply to radial tires at some point in its life.
What size rim does a 1959 Borgward Isabella use?
The 1959 Borgward Isabella uses a 13-inch rim diameter across its supported tire sizes. That applies to the radial sizes 165R13 and 175R13 as well as the bias-ply sizes 590-13 and 640-13, so wheel diameter stays consistent even though tire size and construction vary by sub-model.
Rim diameter is only part of the fitment picture on a vintage car. Wheel width also matters, especially when choosing between a narrow bias-ply fitment and a radial alternative, so it is worth checking the actual wheel on the car before selecting a replacement tire.
Do all 1959 Borgward Isabella sub-models use the same tire size?
No. The 1959 Borgward Isabella Base and TS share the same tire-size pair, while the SW uses a larger pair. Base and TS use 165R13 or 590-13, and the SW uses 175R13 or 640-13, so sub-model identification is necessary before choosing a tire.
That difference matters because selecting by model name alone can lead to the wrong size family. A buyer looking at an SW should not assume the same tire options apply to a Base or TS, and a car with replacement wheels should be checked carefully before changing construction or profile.
Bias-Ply & Radial Options
Is 590-13 a bias-ply or radial tire for the 1959 Borgward Isabella?
590-13 is a bias-ply tire size for the 1959 Borgward Isabella Base and TS. It is the vintage numeric bias-ply fitment associated with those sub-models, while 165R13 serves as the radial size in the same general fitment range for owners comparing original-style construction with a radial alternative.
That distinction affects both appearance and wheel compatibility. A bias-ply tire in 590-13 follows a different sizing convention than a radial, so anyone changing from one construction to the other should confirm wheel width, tire clearance, and the car’s current setup rather than assuming the change is automatic.
What radial tire sizes are equivalent to 640-13?
Radial equivalents for 640-13 include 175R13 as the 80-series metric radial option, P175/75R13 as the 75-series P-metric radial option, P185/70R13 as the 70-series P-metric radial option, and 650R13 as a bias-look radial equivalent. These give the 1959 Borgward Isabella SW several radial-format alternatives to compare.
The practical differences come from sizing style and intended presentation rather than from one option being universally right. The recommended rim-width range for this equivalency is 4 to 6 inches, and any conversion should still be checked for wheel width, clearance, and how the car is actually equipped.
What should I check before converting my 1959 Borgward Isabella from bias-ply to radial tires?
Start by confirming the exact sub-model and original bias-ply size, since the Base and TS use a different size family than the SW. Then compare the intended radial equivalent with the car’s 13-inch wheel setup, including wheel width, because the radial alternatives for 590-13 and 640-13 follow different sizing conventions.
The car should also be inspected for steering and fender clearance, suspension condition, and any previous wheel changes. On a collector car, a conversion can also change the overall visual character, so owners often balance road-use goals against the more traditional look of the original-style bias-ply fitment.
Choosing the Right Tire
What should I consider when choosing a 165R13 tire for a 1959 Borgward Isabella?
A 165R13 tire belongs on the 1959 Borgward Isabella Base or TS when the car is set up for the radial fitment rather than the 590-13 bias-ply option. In this size, available choices include blackwall radials from Michelin and Dunlop, so the main comparisons are tire series, rim-width compatibility, and the kind of period-style radial presentation you want.
Selection should begin with the actual wheel dimensions on the car, especially if it has been restored or altered over time. It also helps to decide whether the goal is a more traditional European radial look or simply a tire that stays within the correct size family for regular driving use.
What sidewall styles are available for 1959 Borgward Isabella tires?
The available sidewall styles for 1959 Borgward Isabella tires include blackwall and wide whitewall. The radial 165R13 choices are blackwall tires, while the bias-ply options offered in 590-13 and 640-13 use wide whitewall sidewalls, creating a clear visual difference between the radial and bias-ply selections.
That makes sidewall style part of the construction decision, not just an appearance detail. A buyer focused on a clean European radial look may lean toward blackwall, while someone restoring the car with a more traditional vintage presentation may prefer the wide whitewall bias-ply sizes matched to the correct sub-model.
What brands offer tires for the 1959 Borgward Isabella?
Tires for the 1959 Borgward Isabella are available from Michelin, Dunlop, and BFGoodrich. Michelin and Dunlop appear in the 165R13 radial fitment, while BFGoodrich covers the 590-13 and 640-13 bias-ply sizes with Silvertown Classic Bias Ply wide whitewall offerings.
Brand choice should come after confirming the correct size and construction for the car. Once that is settled, compare the available series, sidewall style, rim-width compatibility, and any relevant load details, especially if the Isabella has replacement wheels or is being prepared for a specific restoration presentation.
Restoration & Appearance
Which tire should I choose for a period-style 1959 Borgward Isabella?
A period-style 1959 Borgward Isabella usually starts with the correct sub-model size and the construction type that matches the look you want. Base and TS use the 165R13 or 590-13 size family, while the SW uses 175R13 or 640-13, so a period-minded choice begins with that fitment distinction rather than with brand alone.
Bias-ply wide whitewall options create the most traditional presentation among the currently available choices, while blackwall radials keep the car in a classic European radial visual range. When exact originality matters, it is wise to compare the tire choice with marque-specific historical references before finalizing a restoration.
How does tire construction affect the appearance of a restored 1959 Borgward Isabella?
Tire construction changes the visual impression of a restored 1959 Borgward Isabella as much as it affects fitment. The available bias-ply options use wide whitewall sidewalls and a more vintage tire profile, while the radial choices in the Isabella range are blackwall tires with a distinctly European postwar look.
That means construction is often tied directly to restoration intent. A buyer trying to recreate a traditional showroom-era feel may study the bias-ply options first, while someone preserving the car for touring may prefer the radial size associated with that sub-model and accept the different sidewall presentation.
Fitment, Maintenance & Road Use
Can modifications affect tire fitment on a 1959 Borgward Isabella?
Yes. Modifications can change tire fitment on a 1959 Borgward Isabella even when the replacement tire is in the correct size family. Aftermarket wheels, altered wheel width, suspension changes, ride-height adjustments, or bodywork repairs can all affect how a 13-inch tire sits in the wheel opening and how much clearance remains.
That matters even more when moving between the car’s bias-ply and radial fitments, because construction and sizing conventions are different. A modified Isabella should be measured at the wheel and checked through steering travel before choosing a tire based only on the original sub-model fitment.
What should I inspect before driving a 1959 Borgward Isabella on new tires?
Before driving a 1959 Borgward Isabella on new tires, inspect the wheels for correct diameter and condition, make sure the tires are mounted in the proper size for the sub-model, and confirm that there is no interference at the fenders or steering components. Tire pressure should also be checked before the first road use.
It also helps to look over the rest of the car as a complete running system. Old shocks, worn steering parts, weak suspension bushings, or uneven alignment can make a newly installed set feel wrong even when the tire size itself is appropriate for the Base, TS, or SW.
How should 1959 Borgward Isabella tires be maintained on a collector car?
Tires on a collector 1959 Borgward Isabella should be inspected regularly for air loss, sidewall cracking, tread wear, bulges, and cuts, especially if the car spends long periods parked between drives. Keeping the tires properly inflated and moving the car occasionally can help reduce flat-spotting and other storage-related issues.
Storage conditions matter as much as mileage on a vintage car. An Isabella kept away from prolonged sunlight, moisture, heat, and ozone sources will generally give its tires a better environment, and any tire that shows age-related deterioration should be evaluated before the car returns to regular road use.
