Re: [FWDLK] FW: Horsepower Ratings
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Re: [FWDLK] FW: Horsepower Ratings

A.M.A. - Automobile Manufacturers Association   (United States). 
The AMA horsepower figure is based on the engine's bore and number of cyinders with neither the stroke nor compression ratio being taken into consideration.   In Britain is was called R.A.C. horsepower  (Royal Automobile Club).
In both cases, the rating was used for tax purposes.   In Europe cars were taxed annually on the size of the engine, and it was decided that this horsepower 'rating' was the fairest and easiest.   Which almost one hundred years ago, when it was first introduced, it was. 
Which is why you see British cars such as the Austin 7, Morris 8, Ford 10, Wolseley 15/60, etc.   The 7, 8, 10, and 15 refer to the AMA/RAC horsepower rating for that vehicle.   Long stroke engines were the result of such ratings, which was no problem in Europe back then given the short distances and narrow roads common at that time.  
American manufacturers Essex and Studebaker (Erskine) attempted to crack the European market with long stoke sixes in the late 1920's.  However, the cars proved too expensive after shipping and import duties were added and thus were not sold in great numbers over there.  However, back in North America, the long stoke engine proved to be a disaster with the longer distances and higher speeds.  The long-stroke six for the Essex would prove fatal as sales plunged in 1930-31, taking Hudson-Essex from 3rd spot down to the bottom of the top ten.  The Terraplane was introduced in 1933 to replace the Essex.
And as for the Erskine, the engine gave it the kiss of death in its first year, 1927.  In 1930 the long-stroke Continental engine was replaced by a larger Studebaker unit and six months later the car was renamed the Studebaker Six.
But, I digress.
The Canadian Dodge Custom Royal, 361-cid V8 with 2-bbl carb had a10.0:1 compression ratio and put out 290 bhp @ 4600 rpm and had torque rating of 395 @ 3000 rpm.
The same engine was used in the Canadian-built Chrysler Windsor.
Vancouver, BC
----- Original Message -----
Sent: Friday, November 11, 2005 5:24 PM
Subject: [FWDLK] FW: Horsepower Ratings

This was accidentally sent to the ?request? address.


From: Bill/Pat Helm [mailto:modiggers@xxxxxxxxxxx]
Sent: Friday, November 11, 2005 7:03 PM
To: L-FORWARDLOOK-request@xxxxxxxxxxxxx
Subject: Horsepower Ratings


My 1959 Dodge CRL (Canadian) has a 361cid "B series" engine w/2bbl carb.  According to my Canadian shop manual, the A.M.A. horsepower rating is 54.3. 

Can anyone tell me what that means in U.S. terms?

/s/  Bill Helm

Concord, CA



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