Donovan hemi
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The Donovan hemi is an American Top Fuel drag racing 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 {{convert|417|cid|cc|abbr=on}} hemi-head V8 to overcome the tendency of {{convert|392|cid|cc|abbr=on}} Chryslers, then used by Top Fuel racers (many of them friends and customers of his), to crack their iron blocks.
He copied the {{convert|392|cid|cc|abbr=on}}, 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 liners, which were stronger as well as easy to replace. Donovan also enlarged the supports for the main bearings, which Chrysler would do with the B-block. Cast from aluminium rather than iron, the engine weighed under {{convert|200|lb|kg|abbr=on}} bare, compared to {{convert|740|lb|abbr=on}} for the Chrysler.[http://www.hughesengines.com/TechArticles/5engineweights.php Hughes Engines] (retrieved 24 November 2018) Because it closely followed the Chrysler's specification, many hot rodding parts would fit it; only the bore was different, being {{convert|1/8|in|mm|abbr=on}} larger, at {{convert|4.125|in|mm|abbr=on}} (same as the {{convert|400|cid|cc|abbr=on}} Chevrolet.
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.[https://www.turbosquid.com/3d-models/donovan-hemi-engine-3d-model/373647 Turbosquid] (retrieved 24 November 2018) In 1977, Donovan persuaded "Big Daddy" Don Garlits to switch from the 426 hemi he had been using for the last thirteen years to the {{convert|417|cid|cc|abbr=on}}, offering (in Garlits' words), “an engine deal I couldn’t refuse”.[https://www.nhra.com/news/2013/sorting-through-inbox NHRA.com] (retrieved 24 November 2018)
References
{{reflist|refs=
|title=Obituary
|magazine=Hot Rod
|date=September 1989
|pages=132–133
}}
|last=Holmstrom |first=Darwin
|title=Hemi Muscle Cars
|publisher=Motorbooks
|year=2008
|page=287
|isbn=9781616730116
|url=https://books.google.com/books?id=UWBSOG7vqIMC&pg=PA287
|access-date=24 November 2018
}}
}}
External links
- [http://www.donovanengines.com/donovan-417-hemi-aluminum-blocks/ Donovan Engines] website
- [https://www.jalopyjournal.com/forum/threads/snapperhead-coupe-story-of-the-donovan-417-hemi-the-392s-big-brother.1086242/ Jalopy Journal] discussion of the Donovan
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