24 Roadster

4 cylinder engine question

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I am putting together some information on the Dodge Brothers for our local car club.  Could someone send me the correct info on the 4 cylinder engine from 1914 to 1927 (CID and HP)?  I am finding conflicting information.  The book I have says the early engine was 32HP and 213CID.  Then in 1918 went to a 24HP engine.  Is this right?  

 

Thanks for your help,

24 Roadster

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Come on, Someone knows the true history of the early 4 cylinder engine.  Did it start out at 32 HP and then go to 24 HP in 1918?   Going to a smaller engine does not seem right. Or was it the same size from 1914 to 1927?  Roger?

 

Thanks for your help,

24 Roadster

 

 

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I think you would find it was the way they calculated hp that was different. The first was a mathematical equation, the second was actually measured. 

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Using the RAC "horsepower" calculation = bore squared times number of cylinders divided by 2.5, the 1917 engine at 3.87" bore is 24 HP. This method was used in many countries. Some states in the USA used this formula but called it something else. This number is often listed as "Rated HP".

 

According to http://www.remarkablecars.com/main/dodge/1915-dodge.html

the power output of a 1915 was 35 hp @ 2000 RPM.

 

It seems you are confusing measured power output and a calculated HP that by this time bore no relationship to power output. In the early days it was somewhat close.

Edited by Spinneyhill (see edit history)

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Yes, I saw that info.  I also have a book that gives the spec of all DB car from 1914. (The Dodge Story by Thomas McPherson).  It says the 1914 to 1917 was a 213 cu in with 32 HP.  Then in 1918 and forward it list a 212 CU in with 24 HP.  It also says the 1918 had an improved heaver crankshaft.  But it seems to me that the HP should be the same on all engines built from 1914 to 1927 if the same method of measurement is used.  Am I missing something?  Maybe in 1918 they did change the way they were measuring HP.  To further confuse things my dad who bought my 24 Roadster in 1934 also told me it had a 24 HP engine.  I don't know where he got this figure from.  Wow, I did not know this was going to turn into a bag of worms.  Nothing is easy on these old cars.

 

Thanks for all you comments,

Any others are welcome

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"Rated hp" was the taxable horsepower. Engine output nearly always had an RPM value at which it was measured.

 

I wonder if your book has a typo? They may have increased from 32 hp at 2000 rpm to 34 hp at 2000 rpm. All that being said, it was BOTH values, as I said above. It was 24 rated or taxable hp and engine output was 30 to 35 hp at 2000 (later a little more at 2400 rpm).

 

As well, the bore and stroke were the same from 1914 to 1928. 3-7/8 x 4½". The difference of one CID might be due to rounding by two people, one up and one down. Look behind calculated data!

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The Dodge Story book is a great book but certainly far from perfect. Plenty of minor? errors. All the DB fours from 1914 - 1928 were the same cubic inch displacement, 212.3 . Actual horse power? Who knows, they changed cams in '24 or '25, then went away from the starter/generator in mid '26, then went to the so called "fast four" in late '27 which I believe had more power still.

Edited by dwollam (see edit history)

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Some form of dynomomater must have existed back then.  The Ford Model T is usually quoted as having 20 hp (from 177 c.i.).  Would the 36 c.i. make the difference between 20 and 35 hp?  I suspect not but I'm not sure if compression ratios were similar.  They're both L-heads and have similar induction.  Maybe the advance curve on the Dodge?

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