Welcome to the 426 HEMI site
This Site is Dedicated to the Unrepentant Worship of the 426 HEMI Engine and the Muscle Cars They Powered.
There is no other engine in the world more famous for automotive performance than the 426 HEMI
What is a HEMI ?
Many who are unfamiliar with Chrysler's famed 426 HEMI engine are confused as to just exactly what is a HEMI.
A HEMI is an engine with a hemispherical (dome shaped) combustion chamber. The reasoning for this is that it enables the engine valves to be positioned to allow the fuel-air mixture to flow efficiently from the intake to the exhaust and produce maximum performance, especially at high RPM's. Chrysler introduced the concept in American cars in 1951 and it evolved to the now famous 426 HEMI engine in 1964. See the graphic file below to view the "inside" of a simulated 426 HEMI engine. The 426 HEMI engine also had many other features for strength and performance.
There is no other engine in the world more famous for performance than the 426 HEMI ! Read more about the history of the Hemi.
426 HEMI Engine Specifications
| Engine Type: | 90 deg OHV V8 (Hemispherical) |
| Engine Block: | Cast Iron |
| Engine Heads: | Cast Iron (Hemispherical) |
| Engine Mains: | 4-Bolt (cross-bolted) |
| Crankshaft: | Forged Steel |
| Conn Rods: | Forged Steel |
| Pistons: | Forged Aluminum (Hemispherical) |
| Bore x Stroke: | 4.25" x 3.75" |
| Displacement: | 426 cubic inches |
| Horsepower: | 425 HP, 490 Ft-Lbs Torque |
| Comp Ratio: | 10.25 to 1 |
| CC Vol: | 168cc min / 174cc max |
| Valve Dia: | 2.25" Int, 1.94" Exh |
| Cam Type: | Solid lifter (1966-1969) Hydraulic lifter (1970-1971) |
| Cam Lift: | .467" Int, .473" Exh (1966-1969) .490" Int, .481" Exh (1970-1971) |
| Cam Duration: | 276 deg (1966-1967) 284 deg (1968-1971) |
| Intake: | Aluminum Dual-Plane, Dual-Carb |
| Carburation: | 2 x 4-bbl Carter AFB |
| Ignition: | Dual point, vacuum advance |
| Spark Plugs: | N-10Y |
| Firing Order: | 1-8-4-3-6-5-7-2 |
| Exhaust: | Cast Iron Headers, 2.5" outlet |
Will a set of 426 HEMI heads bolt onto my 440?
Answer: NO -- 440 blocks and 426 HEMI heads are not compatible.
What is a the 426 HEMI firing order?
The 426 HEMI firing order is 1-8-4-3-6-5-7-2.
The additional information that is needed is to know how the cylinders are numbered. Looking at the cutaway engine above, the cylinders are numbered 1-3-5-7 on the left side front to rear. Remember that the left side of the engine is the side on the left side of the car. The other cylinders are numbered 2-4-6-8 on the right side front to rear.
A way to remember the cylinder numbering is that the distributor leans "to" the number "two" cylinder. Also, the spark plug wire going to the number "two" cylinder is "too" short to reach anywhere else.