The Donovan hemi is an American

Top Fuel Top Fuel is a type of drag racing whose dragsters are the quickest accelerating racing cars in the world and the fastest sanctioned category of drag racing, with the fastest competitors reaching speeds of and finishing the runs in 3.641 second ...

drag racing Drag racing is a type of motor racing in which automobiles or motorcycles compete, usually two at a time, to be first to cross a set finish line. The race follows a short, straight course from a standing start over a measured distance, mos ...

engine, designed and built by Ed Donovan and first appearing in 1971. In the 1970s, it was the most popular engine in Top Fuel dragsters.

History

Donovan developed the

hemi Hemi may refer to: People Surname * Jack Hemi (1914–1996), New Zealand freezing worker, rugby union and league player, shearer * Ronald Hemi (1933–2000), New Zealand rugby union player Given name * Hemi Bawa, Indian painter and sculptor * ...

head A head is the part of an organism which usually includes the ears, brain, forehead, cheeks, chin, eyes, nose, and mouth, each of which aid in various sensory functions such as sight, hearing, smell, and taste. Some very simple ani ...

V8 to overcome the tendency of

Chrysler FCA US, LLC, Trade name, doing business as Stellantis North America and known historically as Chrysler ( ), is one of the "Big Three (automobile manufacturers), Big Three" automobile manufacturers in the United States, headquartered in Auburn H ...

s, then used by Top Fuel racers (many of them friends and customers of his), to crack their iron

block Block or blocked may refer to: Arts, entertainment and media Broadcasting * Block programming, the result of a programming strategy in broadcasting * W242BX, a radio station licensed to Greenville, South Carolina, United States known as ''96.3 ...

s. He copied the , which he admired, but tried to eliminate its deficiencies. Donovan milled all the internal oil and water passages, and (unlike the stock 392) sleeved the block with chrome- moly

cylinder A cylinder () has traditionally been a three-dimensional solid, one of the most basic of curvilinear geometric shapes. In elementary geometry, it is considered a prism with a circle as its base. A cylinder may also be defined as an infinite ...

liners, which were stronger as well as easy to replace. Donovan also enlarged the supports for the

main bearing A main bearing is a bearing in a piston engine which holds the crankshaft in place and allows it to rotate within the engine block. The number of main bearings per engine varies between engines, often in accordance with the forces produced b ...

s, which Chrysler would do with the B-block. Cast from aluminium rather than iron, the engine weighed under bare, compared to for the Chrysler.Hughes Engines
(retrieved 24 November 2018) Because it closely followed the Chrysler's specification, many

hot rod Hot rods are typically American cars that might be old, classic, or modern and that have been rebuilt or modified with large engines optimized for speed and acceleration. One definition is: "a car that's been stripped down, souped up and ma ...

ding parts would fit it; only the bore was different, being larger, at (same as the

Chevrolet Chevrolet ( ) is an American automobile division of the manufacturer General Motors (GM). In North America, Chevrolet produces and sells a wide range of vehicles, from subcompact automobiles to medium-duty commercial trucks. Due to the promi ...

. Donovan completed work on the engine in 1970, and first sold it in 1971; the first driver to use a Donovan hemi was "Kansas John" Wiebe, at the 1971 NHRA Super Nationals, where Wiebe very nearly won Top Fuel. By 1972, it was commonplace in Top Fuel dragsters, and Altereds would also use it.Turbosquid
(retrieved 24 November 2018) In 1977, Donovan persuaded "Big Daddy" Don Garlits to switch from the

426 hemi The Chrysler Hemi engine, known by the trademark Hemi or HEMI, refers to a series of high-performance American overhead valve V8 engines built by Chrysler with hemispherical combustion chambers. Three generations have been produced: the FireP ...

he had been using for the last thirteen years to the , offering (in Garlits' words), “an engine deal I couldn’t refuse”.NHRA.com
(retrieved 24 November 2018)

References

External links

Donovan Engines
website
Jalopy Journal
discussion of the Donovan {{DEFAULTSORT:Donovan hemi V8 engines Drag racing