1978 Jeep J20 Performance Engines

Keep Your 1978 Jeep J20 in Top Shape with Quality Performance Engines

Whether you’re repairing or upgrading your Performance Engine, using high-quality parts is key to keeping your 1978 Jeep J20 looking sharp and performing at its best. At Advance Auto Parts we carry a wide selection of dependable options, including Performance Engine Timing Sets and Components, Performance Engine Cylinder Head Gaskets, and Performance Engine Rocker Arms. Whether you’re replacing a damaged part or enhancing your truck’s style and protection, you’ll find exactly what you need to get the job done right.

Top-Rated Performance Engines from Trusted Brands

Looking for a reliable Performance Engine? We’ve got you covered with options from brands you know and trust like Competition Cams, Omix, and B & M. For example, Competition Cams Performance Engines start at just $33.99 with an average 4.1 star rating. Omix and B & M offer similar pricing and quality, backed by strong customer feedback. With over 111 reviews and a solid 4 star average, you can shop with confidence knowing other Jeep J20 owners approve.

Explore Related Parts

While you’re upgrading or replacing your Performance Engine, don’t forget to check out other key components like Performance Fuel Systems and Performance Oil Filters. At Advance Auto Parts, we’re here to help you keep your 1978 Jeep J20 in peak condition, inside and out.

Essential 1978 Jeep J20 Performance Engines

Omix – Rocker Arm Bridge; 258CI; 72-06 Jeep CJ/Wrangler YJ/TJ (Part No.17408.11)

Rocker Arm Bridge; 258CI; 72-06 Jeep CJ/Wrangler YJ/TJ

from

$6.49
Direct OE replacement Jeep parts and accessories built to the original specifications by Omix-ADA.

Product Features:
  • Metal
  • OE Style
  • Direct Fit
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B & M – Torque Converter, Nitrous Holeshot 3600 (Part No.20482)

Torque Converter, Nitrous Holeshot 3600

from

$749.99
Nitrous Holeshot Converters are Built with the same features as the other B&M Holeshots, with the addition of anti-balloon plates. The anti-balloon plates will allow these converters to stand up to the instant horsepower nitrous delivers.

Product Features:
  • 3400-3800 RPM
  • Small And Big Blocks
  • Serious Performance
  • Furnace Brazed
  • Fully Balanced
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B & M – Tork Master 2400 (Part No.20404)

Tork Master 2400

from

$373.99
Torque Converter – Tork Master 2400 for GM 1965 to 1991 TH400, 425, 375 and 1968 to 1981 TH350, 375B (not 350C) APPLICATION: Tork Master 2400 for GM 1965 to 1991 TH400, 425, 375 and 1968 to 1981 TH350, 375B (not 350C) The Tork Master is B&M’s lowest cost performance torque converter. The Tork Master is an excellent all-around performance street converter. The best value priced street converters available, Tork Master converters come with a new precision pump drive tube and all are pressure tested and fully balanced. The Tork Master torque converter is not recommended for big block or supercharged applications. New alloy steel pump drive tube. Needle thrust bearing when factory equipped. New thrust washer between turbine and cover when required. Due to torque converter core availability, the actual converter size may vary but performance functionality will be as advertised.

Product Features:
  • New Precision Pump Drive Tube
  • Pressure Tested
  • Fully Balanced
  • Needle Thrust Bearing
  • New Thrust Washer
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B & M – Torque Converter, Nitrous Holeshot 3000 (Part No.20481)

Torque Converter, Nitrous Holeshot 3000

from

$899.99
Nitrous Holeshot Converters are Built with the same features as the other B&M Holeshots, with the addition of anti-balloon plates. The anti-balloon plates will allow these converters to stand up to the instant horsepower nitrous delivers.

Product Features:
  • 2800-3200 RPM
  • Small And Big Blocks
  • Serious Performance
  • Furnace Brazed
  • Fully Balanced
See More

Edelbrock – Pushrod Set for AMC 343-401 (Part No.9637)

Pushrod Set for AMC 343-401

from

$217.99
Product Features:
  • Case-Hardened Tubing
  • Surface Hardening
  • Welded Ends
  • 0.3125 in. Diameter
  • Use with or without Hardened Steel Guideplates
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Omix – Thermostat 180 Degree; 41-71 Willys/Jeep Models (Part No.17106.02)

Thermostat 180 Degree; 41-71 Willys/Jeep Models

from

$8.29
Direct OE replacement Jeep parts and accessories built to the original specifications by Omix-ADA.

Product Features:
  • OE Style
  • Direct Fit
  • Steel
  • Better Flow Control
See More

Mr. Gasket – High Performance 180 Degree Thermostat for Increased Flow (Part No.4364)

High Performance 180 Degree Thermostat for Increased Flow

from

$29.99
Mr. Gasket High Performance Thermostats are designed to resist large variations of coolant pressure at high RPM (revolutions per minute). This allows them to fully open at correct temperature consistently regardless of engine RPM. The design also provides the high flow that engines operated a higher RPM need. This thermostat also features a copper/brass construction to further resist corrosion. Mr. Gasket High Performance / High Flow Thermostats are suitable for street, drag race, or oval track applications.

Product Features:
  • Opens At 180 Degrees
  • Designed to Resist Large Variations of Coolant Pressure at High RPM
  • Fully Opens at Correct Temperature Consistently Regardless of Engine RPM
  • For High Performance Street, Drag Race, and Oval Track
  • Copper & Brass Construction – Resists Corrosion
  • High Flow
See More

Mr. Gasket – High Performance Thermostat – 160 Degree Brass & Copper (Part No.4363)

High Performance Thermostat - 160 Degree Brass & Copper

from

$29.49
Mr. Gasket High Performance Thermostats are designed to resist large variations of coolant pressure at high RPM (revolutions per minute). This allows them to fully open at correct temperature consistently regardless of engine RPM. The design also provides the high flow that engines operated a higher RPM need. This thermostat also features a copper/brass construction to further resist corrosion. Mr. Gasket High Performance / High Flow Thermostats are suitable for street, drag race, or oval track applications.

Product Features:
  • Opens at 160 Degrees
  • Designed to Resist Large Variations of Coolant Pressure at High RPM
  • Fully opens at Correct Temperature Consistently Regardless of engine RPM
  • For High Performance Street, Drag Race, and Oval Track
  • Copper & Brass Construction – Resists Corrosion
  • High Flow
See More

Edelbrock – RPM AMC/ Jeep Cylinder Head With Exhaust Crossover Complete (Part No.60139)

RPM AMC/ Jeep Cylinder Head With Exhaust Crossover Complete

from

$1414.99
Product Features:
  • Complete Single For Flat Tappet (With Crossover Port)
  • 54cc Combustion Chamber Volume
  • 185cc Intake/70cc Exhaust Runner Volume
  • 2.02 in. Intake/1.6 in. Exhaust Valve Diameter
  • 0.625 in. Deck Thickness
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Omix – Timing Chain Kit; 5.9L/6.6L; 79-91 Jeep SJ (Part No.17452.08)

Timing Chain Kit; 5.9L/6.6L; 79-91 Jeep SJ

from

$87.99
Timing chains stretch over time. If left untouched, they can begin jumping teeth on the camshaft and crankshaft sprockets. This will change your timing and will do major damage to your Jeep’s engine. It is recommended that you change the timing chain.

Product Features:
  • 3 Piece Kit
  • OE Style
  • Direct Fit
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Omix – Engine Gasket Set; 5.9L/6.6L; 71-91 Jeep SJ (Part No.17440.08)

Engine Gasket Set; 5.9L/6.6L; 71-91 Jeep SJ

from

$175.99
Are your Jeep’s engine gaskets leaking? Or, are you rebuilding an engine and need fresh gaskets? Omix-ADA offers high-quality replacement gaskets that will give you years of service and get you back on the road.

Product Features:
  • Complete Kit
  • OE Style
  • Direct Fit
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Omix – Engine Gasket Set; Lower V8; 72-91 Jeep CJ/SJ (Part No.17442.07)

Engine Gasket Set; Lower V8; 72-91 Jeep CJ/SJ

from

$77.99
Are your Jeep’s engine gaskets leaking? Or, are you rebuilding an engine and need fresh gaskets? Omix-ADA offers high-quality replacement gaskets that will give you years of service and get you back on the road.

Product Features:
  • Full Lower Gasket Set
  • OE Style
  • Direct Fit
See More

Competition Cams – VALVE SEALS, TEFLON 3/8" 1 ST (Part No.505-16)

VALVE SEALS, TEFLON 3/8" 1 ST

from

$33.99
COMP Cams offers a complete line of valve stem seals, from the umbrella seals to the positive-stop Teflon seal. These seals are a must to keep unwanted oil from entering the combustion chamber through the clearance in the valve guides. The umbrella seal is normally used when a larger-than-stock diameter spring is used, in the case of a double spring, the positive-stop Teflon seal is used. The umbrella seals require no machining, but with the Teflon seal it is necessary to disassemble the heads and machine the top of the guide with a special .530 diameter cutter. Whenever you are planning an engine overhaul or a cam change, don’t forget the valve seals.

Product Features:
  • Work with .530″ guides and 3/8″ valve stem diameter
  • Valve stem oil seals keep unwanted oil from entering the combustion chamber
  • Several different types of valve seals are offered
See More

Edelbrock – Engine Gasket Set (Head / Intake / Exhaust / Valve Cover) for AMC/Jeep (Part No.7372)

Engine Gasket Set (Head / Intake / Exhaust / Valve Cover) for AMC/Jeep

from

$179.99
The Edelbrock #7372?head gaskets provide the best sealing solution and are matched to Edelbrock cylinder heads for optimal performance. Edelbrock relies on industry leading head gasket manufactures to ensure our head gasket sets will provide the best fit

Product Features:
  • Head: 4.275″ Bore/0.045″ Thick/10.60cc Vol.
  • Intake: 1.13″x2.21″ Port/.030″ Thick
  • Exhaust: 1.80″x1.30″ Port
  • 3/16″ Valve Cover
  • Multi Piece Configuration
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Most Popular Performance Engine Timing Sets and Components for 1978 Jeep J20s

Enhance your 1978 Jeep J20 with one of the 2 Performance Engine Timing Sets and Components we have in stock, starting at just $65.99.

Competition Cams – ENGINE TIMING SET (Part No.2118)

ENGINE TIMING SET

from

$129.99
ENGINE TIMING SET

Competition Cams – ENGINE TIMING SET (Part No.3218)

ENGINE TIMING SET

from

$65.99
ENGINE TIMING SET

Best-Selling 1978 Jeep J20 Performance Engine Cylinder Head Gasket

Upgrade your J20 with our best-selling Performance Engine Cylinder Head Gasket.

Edelbrock – Engine Gasket Set (Head / Intake / Exhaust / Valve Cover) for AMC/Jeep (Part No.7372)

Engine Gasket Set (Head / Intake / Exhaust / Valve Cover) for AMC/Jeep

from

$179.99
The Edelbrock #7372?head gaskets provide the best sealing solution and are matched to Edelbrock cylinder heads for optimal performance. Edelbrock relies on industry leading head gasket manufactures to ensure our head gasket sets will provide the best fit

Product Features:
  • Head: 4.275″ Bore/0.045″ Thick/10.60cc Vol.
  • Intake: 1.13″x2.21″ Port/.030″ Thick
  • Exhaust: 1.80″x1.30″ Port
  • 3/16″ Valve Cover
  • Multi Piece Configuration
See More

Top-Quality Performance Engine Rocker Arms for 1978 Jeep J20s

Choose a high-quality OEM or aftermarket Performance Engine Rocker Arm for Jeep J20s and enjoy top-notch performance from $6.49.

Omix – Rocker Arm Bridge; 258CI; 72-06 Jeep CJ/Wrangler YJ/TJ (Part No.17408.11)

Rocker Arm Bridge; 258CI; 72-06 Jeep CJ/Wrangler YJ/TJ

from

$6.49
Direct OE replacement Jeep parts and accessories built to the original specifications by Omix-ADA.

Product Features:
  • Metal
  • OE Style
  • Direct Fit
See More

Competition Cams – Magnum Rocker Arm and Pushrod Kit for AMC 290-401 (Part No.RPM1410-16)

Magnum Rocker Arm and Pushrod Kit for AMC 290-401

from

$517.99
Magnum Rocker Arm and Pushrod Kit for AMC 290-401

Competition Cams – ENGINE ROCKER ARM (Part No.17044-16)

ENGINE ROCKER ARM

from

$277.99
ENGINE ROCKER ARM

Competition Cams – ENGINE ROCKER ARM (Part No.1442-16)

ENGINE ROCKER ARM

from

$241.99
ENGINE ROCKER ARM

Competition Cams – HIGH ENRGY ALUM ROCK (Part No.17044-8)

HIGH ENRGY ALUM ROCK

from

$148.99
HIGH ENRGY ALUM ROCK

Competition Cams – High Energy Rocker with 1.6 Ratio for ’74-’79 AMC with Pedestal Mount (Part No.1210-2)

High Energy Rocker with 1.6 Ratio for '74-'79 AMC with Pedestal Mount

from

$34.99
Four decades after its founding, COMP Cams keeps its focus on producing the highest-performing products possible, providing superior customer service and leading the industry in technological development. That commitment continues to resonate with racers, engine builders and enthusiasts worldwide, making COMP Cams the preferred choice for valve train components. COMP Cams is unrivaled thanks to its engineering staff – the largest and most highly trained in the performance aftermarket industry – sophisticated manufacturing processes, expert technicians and real-world testing on the track and street. The company’s integration of research, engineering and development, coupled with the free technical assistance it offers customers, makes it the Absolute Leader in Valve Train Technology.
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Competition Cams – ENGINE ROCKER ARM (Part No.1442-1)

ENGINE ROCKER ARM

from

$31.99
ENGINE ROCKER ARM

Competition Cams – ENGINE ROCKER ARM (Part No.17044-1)

ENGINE ROCKER ARM

from

$27.99
ENGINE ROCKER ARM

Our Top Pick for a 1978 Jeep J20 Performance Engine Valve Stem Seal Set

Invest in a durable Performance Engine Valve Stem Seal Set for your 1978 Jeep, knowing you’re getting trusted brands and expert craftsmanship.

Competition Cams – VALVE SEALS, TEFLON 3/8" 1 ST (Part No.505-16)

VALVE SEALS, TEFLON 3/8" 1 ST

from

$33.99
COMP Cams offers a complete line of valve stem seals, from the umbrella seals to the positive-stop Teflon seal. These seals are a must to keep unwanted oil from entering the combustion chamber through the clearance in the valve guides. The umbrella seal is normally used when a larger-than-stock diameter spring is used, in the case of a double spring, the positive-stop Teflon seal is used. The umbrella seals require no machining, but with the Teflon seal it is necessary to disassemble the heads and machine the top of the guide with a special .530 diameter cutter. Whenever you are planning an engine overhaul or a cam change, don’t forget the valve seals.

Product Features:
  • Work with .530″ guides and 3/8″ valve stem diameter
  • Valve stem oil seals keep unwanted oil from entering the combustion chamber
  • Several different types of valve seals are offered
See More

Top-Rated Performance Engine Coolant Thermostats for 1978 Jeep J20s

Make a smart move for your 1978 Jeep J20 with products all priced from $8.29 to $31.99.

Omix – Thermostat 180 Degree; 41-71 Willys/Jeep Models (Part No.17106.02)

Thermostat 180 Degree; 41-71 Willys/Jeep Models

from

$8.29
Direct OE replacement Jeep parts and accessories built to the original specifications by Omix-ADA.

Product Features:
  • OE Style
  • Direct Fit
  • Steel
  • Better Flow Control
See More

Mr. Gasket – High Performance 180 Degree Thermostat for Increased Flow (Part No.4364)

High Performance 180 Degree Thermostat for Increased Flow

from

$29.99
Mr. Gasket High Performance Thermostats are designed to resist large variations of coolant pressure at high RPM (revolutions per minute). This allows them to fully open at correct temperature consistently regardless of engine RPM. The design also provides the high flow that engines operated a higher RPM need. This thermostat also features a copper/brass construction to further resist corrosion. Mr. Gasket High Performance / High Flow Thermostats are suitable for street, drag race, or oval track applications.

Product Features:
  • Opens At 180 Degrees
  • Designed to Resist Large Variations of Coolant Pressure at High RPM
  • Fully Opens at Correct Temperature Consistently Regardless of Engine RPM
  • For High Performance Street, Drag Race, and Oval Track
  • Copper & Brass Construction – Resists Corrosion
  • High Flow
See More

Mr. Gasket – High Performance Thermostat – 160 Degree Brass & Copper (Part No.4363)

High Performance Thermostat - 160 Degree Brass & Copper

from

$29.49
Mr. Gasket High Performance Thermostats are designed to resist large variations of coolant pressure at high RPM (revolutions per minute). This allows them to fully open at correct temperature consistently regardless of engine RPM. The design also provides the high flow that engines operated a higher RPM need. This thermostat also features a copper/brass construction to further resist corrosion. Mr. Gasket High Performance / High Flow Thermostats are suitable for street, drag race, or oval track applications.

Product Features:
  • Opens at 160 Degrees
  • Designed to Resist Large Variations of Coolant Pressure at High RPM
  • Fully opens at Correct Temperature Consistently Regardless of engine RPM
  • For High Performance Street, Drag Race, and Oval Track
  • Copper & Brass Construction – Resists Corrosion
  • High Flow
See More

Mr. Gasket – High Performance Thermostat (Part No.4365)

High Performance Thermostat

from

$31.99
Mr. Gasket High Performance Thermostats are designed to resist large variations of coolant pressure at high RPM (revolutions per minute). This allows them to fully open at correct temperature consistently regardless of engine RPM. The design also provides the high flow that engines operated a higher RPM need. This thermostat also features a copper/brass construction to further resist corrosion. Mr. Gasket High Performance / High Flow Thermostats are suitable for street, drag race, or oval track applications.

Product Features:
  • Opens At 195 Degrees
  • Designed to Resist Large Variations of Coolant Pressure at High RPM
  • Fully Opens at Correct Temperature Consistently Regardless of Engine RPM
  • For High Performance Street, Drag Race, and Oval Track
  • Copper & Brass Construction – Resists Corrosion
  • High Flow
See More

Top-Rated Performance Engine Brands For Your 1978 Jeep J20

When it comes to finding the perfect Performance Engine for your 1978 Jeep J20, Advance Auto Parts has you covered with a wide selection of high-quality OEM and aftermarket options from 5 trusted brands. We carry the most popular Performance Engine brands including Omix, Competition Cams, and B & M, and more, all known for their exceptional customer ratings (average brand rating of 4.3 stars) and competitive prices, as low as $8.29. Purchasing a Performance Engine from us here at Advance Auto Parts is a smart move for both you and your 1978 Jeep J20, providing peace of mind with parts that meet or exceed OEM standards.

Popular Omix 1978 Jeep J20 Performance Engines

If you’re looking for a top-quality Performance Engine for your 1978 Jeep J20, Advance Auto Parts has exactly what you need with our selection of Omix Performance Engines. We have 1 Omix Performance Engines in stock for this fitment, all known for their durability and precision fit. With prices starting at just $8.29, you’ll find the perfect Performance Engine for your needs and budget. Omix Performance Engines for the 1978 Jeep J20 come highly rated, with over 2 customer reviews and an impressive average rating of 4.3 stars. Choosing a Omix Performance Engine from Advance Auto Parts is a smart move to ensure quality and value for your vehicle.
Thermostat 180 Degree; 41-71 Willys/Jeep Models
from $8.29
(2)
Thermostat 180 Degree; 41-71 Willys/Jeep Models
“Product is great. Installing next weekend to my jeep”

Top-Quality Competition Cams 1978 Jeep J20 Performance Engines

For those in search of a high-quality Performance Engine for their 1978 Jeep J20, Advance Auto Parts offers a great selection of Competition Cams Performance Engines. With 1 Competition Cams Performance Engines in stock, you can trust you’re getting top-tier parts designed for durability and a perfect fit. Prices for these Performance Engines start at just $33.99, giving you a range of options to suit your budget. Backed by over 1 customer ratings and an average rating of 4.1 stars, Competition Cams Performance Engines provide both reliability and excellent performance. Choosing a Competition Cams Performance Engine from Advance Auto Parts is a smart investment in your vehicle’s performance and longevity.
VALVE SEALS, TEFLON 3/8" 1 ST
from $33.99
(1)
VALVE SEALS, TEFLON 3/8" 1 ST
“As good as OEM.”

FAQs for 1978 Jeep J20 Performance Engines

What are the best-selling Performance Engines for 1978 Jeep J20s?

Out of 46 Performance Engines that fit 1978 Jeep J20s, the following parts are the top sellers:

What’s the price range for 1978 Jeep J20 Performance Engines?

The prices of Performance Engines for the 1978 Jeep J20 range from $6.49 up to $1,414.99 for the most premium parts.

What is the average price of a Performance Engine for a 1978 Jeep J20?

The average price for Performance Engines for the 1978 Jeep J20 is $298.01. Keep in mind the variety of part types within our Performance Engine category, where you are likely to find a wide range of prices across a variety of parts and components.

Does Advance Auto Parts sell Performance Engines for other Jeep J20 model years?

Yes, we carry Performance Engines for 13 model years of Jeep J20s between 1974 and 1988. The following model years are the most popular for Performance Engine purchases: 1988, 1987, 1986, 1985, 1984, 1983, 1982, 1981, and 1980.

What are the cheapest Performance Engines for my 1978 Jeep J20?

Does Advance Auto Parts sell Performance Engines for any other 1978 Jeep models?

Yes. We stock Performance Engines for 5 other popular 1978 Jeep models. Some of the most popular are 1978 Cherokee Performance Engines, 1978 Wagoneer Performance Engines, 1978 J10 Performance Engines, 1978 CJ7 Performance Engines, and 1978 CJ5 Performance Engines.

What are the top-rated Performance Engines that fit the 1978 Jeep J20?

The one 1978 Jeep J20 Performance Engine we have in stock is the Rocker Arm Bridge; 258CI; 72-06 Jeep CJ/Wrangler YJ/TJ. It costs $6.49.

What types of Performance Engines do you sell for my 1978 Jeep J20?

As of 11/2/25, these are some of the most in-demand types of Performance Engines for a 1978 Jeep J20:

Can I get help with 1978 Jeep J20 Performance Engine orders?

Contact our customer support team by chat or phone, through the help desk page, where you can find instant answers about Jeep Performance Engines and more.

What is your return policy for Jeep J20 Performance Engines?

Advance Auto Parts keeps returns simple. For new Jeep J20 Performance Engines and accessories, your online orders can be returned, in their original condition, within 45 days. For requirements, see the returns page.