Mopar Engines

Many people like to talk about the rarity of a particular car model or engine option. This is especially true discussing the iconic 426 Hemi engine. How rare is a 426 Hemi? During the 426 Hemi’s production, only 0.7% of the car models which offered the engine as an option were produced with the 426…

Many people wonder how many 426 Hemi engines were produced for cars available to the public. There was a total of 10,669 426 Hemi engines produced for production cars between 1964 through 1971. This figure includes race and street versions. Of the 10,669 426 Hemi engines produced for production cars, the following is a breakdown…

Many Mopar owners wonder what their stock 426 Hemi should idle at or was set by the factory. The following are the 426 Hemi idle speed specs for each year. This article will dive into more detail including the fast idle speed specifications for each year. In addition, I’ll explain the discrepancy in 1969 and…

Mopar tuning tips.

The 426 Hemi head torque sequence and torque specs for the cylinder head bolts and nuts is a question often asked. A factory 426 Hemi head cylinder bolts and nuts are torqued to 75 foot-pounds. The head bolts and stud nuts are torqued in two steps, first 50 ft. lbs. then 75 ft. lbs., while…

You may be wondering what that old Hemi cylinder head casting number for sale is or collecting dust in your neighbor’s garage. The following are the 426 Hemi head casting numbers for the production street and race cylinder heads: The following 426 Hemi head casting numbers are for less common, experimental or revised race cylinder…

There are many ways to identify the iconic Hemi. Sometimes a quick visual inspection will tell you, how to identify a 426 Hemi? A 426 Hemi engine is identified by its casting #2468330. It has wide black valve covers with the spark plug wires through the center. The engine has its distributor in the right…

Since both engines are iconic and share the same cubic inches, many people ask about their differences. Let’s answer, what is the difference between a 426 Hemi and a 426 Wedge? The main difference between a 426 Hemi and 426 Wedge is the cylinder head design. Hemi has a hemispherical combustion chamber and the Wedge…

One of the common questions about the 426 Hemi is its pistons, rings and wrist pins. Let’s examine, what size pistons are in a 426 Hemi? 426 Hemi pistons are made to fit the 4.250″ bore size. They weigh 841-845 grams and have an overall length of 4.060 in. The wrist pin size is 1.0310″-1.0312″…

Knowing the deck height may help when modifying the engine or doing a stock rebuild. Let’s answer, what is the deck height of a 426 Hemi? The deck height of a 426 Hemi is 10.725 inches. The deck height is the distance from the centerline of the crankshaft to the deck surface of the block….

For people tuning their own engine, knowing the firing order of their Mopar is crucial. Let’s find out what is the firing order on a 426 Hemi? The 426 Hemi firing order is 1-8-4-3-6-5-7-2. This article will inform you where the cylinder numbers are located on the engine. In addition, where they are on the…

Due to the resurgence of the Hemi Engine and its iconic history, many questions are asked about it. One often asked is, what is the largest Hemi ever made? The largest Hemi ever made for production cars is the 426 Hemi produced by Chrysler from 1966 to 1971. The race version of the 426 Hemi…

One of the questions asked about the Hemi engine is gas mileage. When driving a beast like this, who cares? Even though, let’s answer, how many miles per gallon did a 426 Hemi get? 426 Hemi cars averaged 11 miles per gallon overall with a range between 7 and 14 MPG. The lower end represents…

The Hemi intake manifold installation and torque specs can be a confusing topic. It’s due to the different screws and studs why people ask many questions. Let’s take a close look at the 426 Hemi Intake Manifold torque specs. The 426 Hemi intake manifold has two different torque specifications. The middle eight screws and nuts…

The Chrysler engineers changed some details during the production run of the 426 Hemi. One of those changes was the oil capacity of the engine. Let’s answer, what was the 426 Hemi oil capacity? The 426 Hemi oil capacity was 6 quarts, five quarts for the oil pan and one for the filter, from 1966…

The 426 Hemi Engine is known mostly for its cylinder head design. This sometimes makes people wonder about the lesser known internals of the engine like the camshaft. Let’s take a close look at the 426 Hemi cam specs. The 426 street Hemi in 1966 and 1967 had a cam duration of 276 degrees with…

Many questions popup overtime about Chrysler’s most iconic engine ever produced. One of the topics asked about is the 426 Hemi compression ratio. The 426 street Hemi had a 10.25:1 compression ratio. This engine was produced by Chrysler with the same ratio from 1966 to 1971. The 426 Race Hemi had a 12.5:1 compression ratio…

The 426 Hemi did have some problems during development and post production. Let’s take a close look at them by answering the question, what problems did the 426 Hemi Have? During development the engine blocks were cracking and the piston wrist pin assembly was failing. Post-production there was carburetor related issues like idling and difficulty…

The 426 Hemi engine is legendary. Therefore, why wouldn’t anybody want a new one today? For this reason many people ask, do they still make a 426 Hemi? Dodge, owned by Stellantis, currently produces a 426 Hemi crate engine called the Hellephant. The Hellephant was announced in 2018 and released in 2020. It is not…

Chrysler eight cylinder engines came in big block or small block designs. For this reason some people wonder and ask, is a 426 Hemi a big block? The 426 Hemi is a big block Chrysler engine first released in 1964 for racing. Its Hemispherical cylinder heads were designed to bolt on to a modified big…

The heads on a 426 Hemi is what gives the engine its true power. The Hemi Heads are designed for more power than 440 heads. For this reason many people ask, can you put 426 Hemi heads on a 440? Stock 426 Hemi heads cannot be placed onto a factory stock 440 engine block without…

Most of the newer car manufacturers advertise the size of their engines in liters. When the Hemi was around it was all about cubic inches. This makes many people wonder how many liters is a 426 Hemi? A 426 Hemi is 7.0 L rounded off. The exact liter measurement of the 426 Hemi is 6.980889263397393…

The Hemi Engine was such a huge success and is iconic in the automotive industry. For this reason many people wonder who invented the 426 Hemi and designed it. The 426 Hemi Engine was invented by the Chrysler Corporation headed by President Lynn Townsend who commissioned and approved the development. Assistant Chief Engineer Willem Weertman…

With an engine as iconic as the 426 Hemi, many people want to know everything about it. This includes where it was actually built. The 426 Hemi Engine block and cylinder heads were cast and manufactured at the Indianapolis Foundry located in Indiana. The block and head castings were then sent to the Marysville, Michigan…

The 426 race Hemi came before the 426 street versions. To make the race engine more streetable, changes had to be made. Many people ask me how they differ. Let’s examine the differences between the two engines. The differences between a 426 Street and race Hemi are the street version’s lower compression ratio of 10.25:1…

During the muscle car era, the Hemi and Six Pack were Chryslers two most powerful engines. Some Mopar fanatics can debate all day about which one is faster, the 426 Hemi or the 440 Six Pack? The 426 Hemi was faster than the 440 Six Pack in the 1/4 mile and 0-60 elapsed times recorded…

I’m often asked about the 426 Hemi and its specifications. One topic coming up is about an overhead cam design. Let’s answer, is the 426 Hemi DOHC? The 426 Hemi is not an overhead cam design engine. A 426 Hemi dual overhead cam engine was designed as a prototype in 1964 but was never completed…

Few words in the muscle car world are more recognizable than the word Hemi. The 426 Hemi is so iconic its been given a few nicknames, like the elephant. Why is it called the elephant engine? The 426 Hemi is called the elephant engine due to its wide size, weight and power. It is one…

The 426 Hemi is spoken about all the time. The less celebrated transmission doesn’t come up as often. After all, it plays an important role in the transfer of all that power. Therefore, let’s discuss what transmissions came with the 426 Hemi. The 426 Hemi came with two different transmissions, either the A-727 Torqueflite automatic…