This page lists 46 ignition parts for the 1978 MG MGB, across 10 part types, covering the 1.8L L4 engine. Every part shows its brand, manufacturer part number and fitment notes.
On the 1978 MG MGB, the ignition system delivers spark at the right moment — plugs, coils, wires, distributors and ignition modules. Most of the listed parts are Spark Plug (20 parts), Spark Plug Wire (8 parts) and Ignition Coil (7 parts). The other 7 part types cover the remaining 11 parts.
The 1978 MG MGB came with a single engine, the 1.8L L4, and every part is verified against it.
16 brands supply ignition parts for the 1978 MG MGB, led by STANDARD MOTOR PRODUCTS (8 parts), NGK (7 parts) and WELLS (5 parts), plus 13 more brands. Quality grades include Copper / Nickel, Standard Replacement and Iridium.
A "Popular" badge means the source catalog flagged the part as frequently chosen for the 1978 MG MGB. 8 parts have it, including SPECTRA PREMIUM C632 (Ignition Coil) and BOSCH 7900 (Spark Plug). Each part number opens a page with every vehicle that part fits.
Ballast Resistor
Economy
| Brand | Part Number | Markets | Notes | Buy |
|---|---|---|---|---|
| STANDARD MOTOR PRODUCTS | RU10T | 🇺🇸 US 🇨🇦 CA | T-Series | View on Amazon |
Standard Replacement
| Brand | Part Number | Markets | Notes | Buy |
|---|---|---|---|---|
| STANDARD MOTOR PRODUCTS | RU10 | 🇺🇸 US 🇨🇦 CA | View on Amazon |
This table covers the Ballast resistors.
2 Ballast Resistor parts for the 1978 MG MGB come from STANDARD MOTOR PRODUCTS.
The Economy section lists 1 option from STANDARD MOTOR PRODUCTS — the catalog's value-priced group. STANDARD MOTOR PRODUCTS RU10T is listed in this group.
In the Standard Replacement grade, STANDARD MOTOR PRODUCTS supplies 1 part: built to original-equipment specification. A representative part number is STANDARD MOTOR PRODUCTS RU10.
Listed part numbers: STANDARD MOTOR PRODUCTS RU10T and STANDARD MOTOR PRODUCTS RU10.
Distributor Cap
| Brand | Part Number | Markets | Notes | Buy |
|---|---|---|---|---|
| STANDARD MOTOR PRODUCTS | LU430 | 🇺🇸 US 🇨🇦 CA | View on Amazon | |
| WELLS | 5D1042 | 🇺🇸 US 🇨🇦 CA | View on Amazon |
This table covers the Distributor caps. Typical signs include a leak at the neck, a cap that will not hold pressure, or a missing tether. Match the pressure rating or thread in the notes — radiator, reservoir and fuel caps are not interchangeable.
2 Distributor Cap parts are listed for the 1978 MG MGB, from STANDARD MOTOR PRODUCTS and WELLS.
Listed part numbers: STANDARD MOTOR PRODUCTS LU430 and WELLS 5D1042.
Distributor Reluctor
| Brand | Part Number | Markets | Notes | Buy |
|---|---|---|---|---|
| WELLS | 1A4052 | 🇺🇸 US 🇨🇦 CA | View on Amazon |
This table covers the Distributor reluctors.
One part is listed for the 1978 MG MGB — WELLS 1A4052.
Distributor Rotor
| Brand | Part Number | Markets | Notes | Buy |
|---|---|---|---|---|
| STANDARD MOTOR PRODUCTS | LU324 | 🇺🇸 US 🇨🇦 CA | View on Amazon | |
| WELLS | 4R1189 | 🇺🇸 US 🇨🇦 CA | View on Amazon |
This table covers the Distributor rotors. Typical signs include shudder under braking, or a lip at the outer edge. Do not put new pads on a rotor that is below minimum thickness.
2 Distributor Rotor parts are listed for the 1978 MG MGB, from STANDARD MOTOR PRODUCTS and WELLS.
Part numbers include STANDARD MOTOR PRODUCTS LU324 and WELLS 4R1189.
Ignition Coil
Economy
| Brand | Part Number | Markets | Notes | Buy |
|---|---|---|---|---|
| SPECTRA PREMIUM Popular | C632 | 🇺🇸 US 🇨🇦 CA | Pack | View on Amazon |
| HOLSTEIN | 2IGC0146 | 🇺🇸 US 🇨🇦 CA | View on Amazon |
Standard Replacement
| Brand | Part Number | Markets | Notes | Buy |
|---|---|---|---|---|
| WELLS Popular | 5C1057 | 🇺🇸 US 🇨🇦 CA | Requires External Resistor: YES | View on Amazon |
| BECK/ARNLEY | 1788074 | 🇺🇸 US 🇨🇦 CA | Electronic Ignition | View on Amazon |
| STANDARD MOTOR PRODUCTS | UF2 | 🇺🇸 US 🇨🇦 CA | View on Amazon | |
| UNITED MOTOR PRODUCTS | C2 | 🇺🇸 US 🇨🇦 CA | View on Amazon | |
| WALKER PRODUCTS | 9201017 | 🇺🇸 US 🇨🇦 CA | Single Coil | View on Amazon |
This table covers the coils that fire each spark plug. Typical signs include a misfire that follows one cylinder, a snap in damp weather, or a coil that is swollen or cracked. Swap a suspect coil with a neighbor to confirm, then replace boots that tore on the way off.
7 Ignition Coil parts for the 1978 MG MGB come from 7 brands — SPECTRA PREMIUM, HOLSTEIN, WELLS and 4 other brands. The "Popular" part is SPECTRA PREMIUM C632.
The Economy section: 2 options from SPECTRA PREMIUM and HOLSTEIN. SPECTRA PREMIUM C632 is listed in this group.
Standard Replacement: 5 parts, from WELLS, BECK/ARNLEY, STANDARD MOTOR PRODUCTS and 2 other brands. A representative part number is WELLS 5C1057.
Part numbers include SPECTRA PREMIUM C632, HOLSTEIN 2IGC0146 and WELLS 5C1057, among others listed above.
Ignition Conversion Kit
| Brand | Part Number | Markets | Notes | Buy |
|---|---|---|---|---|
| STANDARD MOTOR PRODUCTS | LX806 | 🇺🇸 US 🇨🇦 CA | View on Amazon | |
| WELLS | 1A4175 | 🇺🇸 US 🇨🇦 CA | with Lucas Distributor # 45DM4, 45DE412 Volt | View on Amazon |
This table covers the Ignition Conversion kits.
2 Ignition Conversion Kit parts are listed for the 1978 MG MGB, from STANDARD MOTOR PRODUCTS and WELLS.
Part numbers include STANDARD MOTOR PRODUCTS LX806 and WELLS 1A4175.
Ignition Lock Cylinder
| Brand | Part Number | Markets | Notes | Buy |
|---|---|---|---|---|
| ÜRO PARTS | BHM7144 | 🇺🇸 US 🇨🇦 CA | View on Amazon |
This table covers the lock cylinders in the ignition switch.
This group shows a single part: ÜRO PARTS BHM7144.
Spark Plug
Summary: Notes include pre-set gaps of 0.03", 0.031", 0.032", 0.035", 0.036", 0.040", 0.041" and 0.044". Replacement brands in this table include NGK, CHAMPION and DENSO.
Copper / Nickel
| Brand | Part Number | Markets | Notes | Buy |
|---|---|---|---|---|
| BOSCH Popular | 7900 | 🇺🇸 US 🇨🇦 CA | NickelPre-Set Gap: 0.031" | View on Amazon |
| NGK Popular | 4008 | 🇺🇸 US 🇨🇦 CA | StandardPre-Set Gap: 0.032" | View on Amazon |
| ACDELCO | R42XLS | 🇺🇸 US 🇨🇦 CA | ProfessionalConventional | View on Amazon |
| CHAMPION | 415 | 🇺🇸 US 🇨🇦 CA | Copper PlusPre-Set Gap: 0.032" | View on Amazon |
| CHAMPION | 300 | 🇺🇸 US 🇨🇦 CA | Copper PlusPre-Set Gap: 0.032" | View on Amazon |
| CHAMPION | 4151 | 🇺🇸 US 🇨🇦 CA | Copper PlusClassification: Champion Copper Plus Small Engine | View on Amazon |
| DENSO | 3066 | 🇺🇸 US 🇨🇦 CA | U-Groove ConventionalHex Size: 20.6 mm | View on Amazon |
| NGK | 6427 | 🇺🇸 US 🇨🇦 CA | V-PowerPre-Set Gap: 0.032" | View on Amazon |
| NGK | 7131 | 🇺🇸 US 🇨🇦 CA | StandardPre-Set Gap: 0.036" | View on Amazon |
Double Platinum (lasts up to 3x longer than Copper / Nickel)
| Brand | Part Number | Markets | Notes | Buy |
|---|---|---|---|---|
| ACDELCO | 41804 | 🇺🇸 US 🇨🇦 CA | ProfessionalDouble Platinum | View on Amazon |
| CHAMPION | 7415 | 🇺🇸 US 🇨🇦 CA | Double Platinum PowerPre-Set Gap: 0.032" | View on Amazon |
Iridium (lasts up to 4x longer than Copper / Nickel)
| Brand | Part Number | Markets | Notes | Buy |
|---|---|---|---|---|
| NGK Popular | 6637 | 🇺🇸 US 🇨🇦 CA | Iridium IXPre-Set Gap: 0.032" | View on Amazon |
| CHAMPION | 9804 | 🇺🇸 US 🇨🇦 CA | IridiumPre-Set Gap: 0.03" | View on Amazon |
| DENSO | 5306 | 🇺🇸 US 🇨🇦 CA | Iridium PowerHex Size: 20.6 mm | View on Amazon |
| DENSO | 4709 | 🇺🇸 US 🇨🇦 CA | Iridium TTSolid Terminal | View on Amazon |
| SKP | SP1041 | 🇺🇸 US 🇨🇦 CA | Tapered Ground Electrode with Platinum Chip | View on Amazon |
Platinum (lasts up to 2x longer than Copper / Nickel)
| Brand | Part Number | Markets | Notes | Buy |
|---|---|---|---|---|
| NGK Popular | 7084 | 🇺🇸 US 🇨🇦 CA | G-PowerPre-Set Gap: 0.040" | View on Amazon |
| ACDELCO | 4 | 🇺🇸 US 🇨🇦 CA | ProfessionalRapidfire | View on Amazon |
| DENSO | 4502 | 🇺🇸 US 🇨🇦 CA | Platinum TTSolid Terminal | View on Amazon |
| NGK | 6764 | 🇺🇸 US 🇨🇦 CA | Platinumuse Iridium #6637 | View on Amazon |
This table covers the spark plugs for this engine. Typical signs include misfire under load, rough idle, or a flashing check-engine light. Verify the gap even on pre-gapped plugs, and replace coil boots that come off a high-mileage engine.
20 Spark Plug parts are listed for the 1978 MG MGB, from NGK, CHAMPION, DENSO and 3 other brands. BOSCH 7900 carries the "Popular" badge.
In the Copper / Nickel grade, NGK, CHAMPION, BOSCH and 2 other brands supply 9 parts: grouped under the catalog's "Copper / Nickel" designation — the notes column spells out what sets them apart. A representative part number is BOSCH 7900.
In the Double Platinum (lasts up to 3x longer than Copper / Nickel) grade, ACDELCO and CHAMPION supply 2 parts: grouped under the catalog's "Double Platinum (lasts up to 3x longer than Copper / Nickel)" designation — the notes column spells out what sets them apart. A representative part number is ACDELCO 41804.
The Iridium (lasts up to 4x longer than Copper / Nickel) section lists 5 options from DENSO, NGK, CHAMPION and 1 other brand — grouped under the catalog's "Iridium (lasts up to 4x longer than Copper / Nickel)" designation — the notes column spells out what sets them apart. NGK 6637 is listed in this group.
In the Platinum (lasts up to 2x longer than Copper / Nickel) grade, NGK, ACDELCO and DENSO supply 4 parts: grouped under the catalog's "Platinum (lasts up to 2x longer than Copper / Nickel)" designation — the notes column spells out what sets them apart. A representative part number is NGK 7084.
Spark Plug Non-Fouler
| Brand | Part Number | Markets | Notes | Buy |
|---|---|---|---|---|
| DORMAN | 42004 | 🇺🇸 US 🇨🇦 CA | 14mm Gasket Seat Long Reach | View on Amazon |
This table covers the non-foulers that space a spark plug away from oil fouling.
This group shows a single part: DORMAN 42004.
Spark Plug Wire
Economy
| Brand | Part Number | Markets | Notes | Buy |
|---|---|---|---|---|
| B&B | S428224 | 🇺🇸 US 🇨🇦 CA | Suppressor Wire Set | View on Amazon |
Premium
| Brand | Part Number | Markets | Notes | Buy |
|---|---|---|---|---|
| NGK Popular | 54406 | 🇺🇸 US 🇨🇦 CA | Set | View on Amazon |
| DENSO | 6714018 | 🇺🇸 US 🇨🇦 CA | Spark Plug Wire Set7mm | View on Amazon |
| STANDARD MOTOR PRODUCTS | 55429 | 🇺🇸 US 🇨🇦 CA | IntermotorSet | View on Amazon |
| UNITED MOTOR PRODUCTS | 9409 | 🇺🇸 US 🇨🇦 CA | SetUnited-Packard | View on Amazon |
Standard Replacement
| Brand | Part Number | Markets | Notes | Buy |
|---|---|---|---|---|
| STANDARD MOTOR PRODUCTS Popular | 29436 | 🇺🇸 US 🇨🇦 CA | Pro SeriesSet | View on Amazon |
| B&B | M428224 | 🇺🇸 US 🇨🇦 CA | Platinum Class Laser Mag | View on Amazon |
| WALKER PRODUCTS | 9241008 | 🇺🇸 US 🇨🇦 CA | Direct FitSet | View on Amazon |
This table covers the Spark Plug wires.
8 Spark Plug Wire parts for the 1978 MG MGB come from 6 brands — B&B, STANDARD MOTOR PRODUCTS, NGK and 3 other brands. The "Popular" part is NGK 54406.
The Economy section: 1 option from B&B. B&B S428224 is listed in this group.
In the Premium grade, NGK, DENSO, STANDARD MOTOR PRODUCTS and 1 other brand supply 4 parts: a step above OE specification in materials, tolerances or warranty terms. A representative part number is NGK 54406.
Standard Replacement: 3 parts, from STANDARD MOTOR PRODUCTS, B&B and WALKER PRODUCTS. A representative part number is STANDARD MOTOR PRODUCTS 29436.
Part numbers include NGK 54406, B&B S428224 and DENSO 6714018, among others listed above.
Buying Ignition Parts for a 1978 MG MGB
On this vehicle, the ignition system delivers spark at the right moment — plugs, coils, wires, distributors and ignition modules.
- Confirm you have the 1.8L L4 engine — every part on this page is matched to it.
- Read the notes on each row for position, trim and spec qualifiers before you order.
- Where labor overlaps, replace plugs and wires (or coil boots) as a set — one weak cylinder makes the whole set feel bad.
- Cross-reference the manufacturer part number against your old part or a service-manual listing.
Start with the largest groups on this page: Spark Plug and Spark Plug Wire .
Frequently Asked Questions
How many ignition parts fit the 1978 MG MGB?
Our catalog currently lists 46 ignition parts for the 1978 MG MGB across 10 subcategories and 16 brands, covering the 1.8L L4 engine. Each part is matched to the engine(s) it fits.
What are the signs of ignition problems on a 1978 MG MGB?
Common symptoms include misfires under load, rough idle, flashing check-engine light, or poor starting in damp weather. If you notice any of these, identify the affected subcategory above and cross-reference the part numbers listed.
What spark-plug gap is listed for the 1978 MG MGB?
Notes on this page include pre-set gaps of 0.03", 0.031", 0.032", 0.035", 0.036", 0.040", 0.041" and 0.044". Still verify against spec — even “pre-gapped” plugs should be checked before they go in.
What should I replace at the same time?
Where labor overlaps, replace plugs and wires (or coil boots) as a set — one weak cylinder makes the whole set feel bad.
What do the market flags (US, CA, MX) on each part mean?
They show the market for which the manufacturer published application data for that part — where the vehicle was first sold, not where the part was made. If your 1978 MG MGB was originally sold in the US, the safest choice is a part marked for the US market.
How do I make sure a part fits my 1978 MG MGB?
Every part on this page is matched to the 1.8L L4 engine. Then gap matters even on “pre-gapped” plugs — verify against spec, and replace coil boots when they come off a high-mileage engine. The notes column carries position and trim qualifiers where they apply.
Other Parts for the 1978 MG MGB
Ignition Parts for Other MG MGB Years
Switch vehicle or jump to a subcategory
Manufacturer names, model designations and part numbers are used for identification and fitment reference only. AutoFactsDB is an independent catalog and is not affiliated with, endorsed by, or sponsored by any vehicle manufacturer displayed on this page.