23" and 25" engines

[meadowbrook]

I'm curious about the differences between these 2 engines, as I understand it, there pretty much have nothing in common, and the 25 incher was a DeSoto and  Chrysler  engine in the US. 

Are both related to the initial 4 cylinder used in the 30s in Plymouths? 

Are these engines all descended from the inline 6 that had its head developed by Ricardo in the 20's? 

The 23" is the more common one and the one with easier parts availability, no? 

 

[austinsailor]

Some parts are interchangeable. Pistons if the same bore, oil pump, I think flywheels, bell housings. 

[55 Fargo]

Basically yes for the USA, but not for Canada, for simplicity a market only 10% of the US, Canada built only long block engines, 201.218,228,238,241,250,265.

The rods on the shorter engines are off set, basic design principle much the same though.

If you are referring to aftermarket performance parts, yes, much more for the shorter engines.

But for all power, no replacement for displacement and a 250 or 265 fits the bill.

I am sure there are more diversities that shorter engine owners could mention...

[51custom]

Aftermarket for the 251 is pretty much nonexistent as its mainly old stock that is randomly sold on ebay and or having it made.  AOK in Western PA still makes intakes for the 251.  From what I've read and what has been described above the 251-265 are more powerful than the 230 and other non chrysler/desoto brands.  Basically outside of this forum the mopar flatheads are regarded as strong and reliable but not as powerful as the their ford/chevrolet counterparts.  Don has a wealth of knowledge on the 25 inch desoto/chrysler block.

[55 Fargo]

1 hour ago, 51custom said:

Aftermarket for the 251 is pretty much nonexistent as its mainly old stock that is randomly sold on ebay and or having it made.  AOK in Western PA still makes intakes for the 251.  From what I've read and what has been described above the 251-265 are more powerful than the 230 and other non chrysler/desoto brands.  Basically outside of this forum the mopar flatheads are regarded as strong and reliable but not as powerful as the their ford/chevrolet counterparts.  Don has a wealth of knowledge on the 25 inch desoto/chrysler block.

I would name Tim Kingsbury as the most knowledgeable member on this or any other forum for that matter for Performance Chrysler flathead 6s.

Your really need to read his Blogs, in order to get a full appreciation for Tims, experience, history and knowledge on this topic.

Dpollo, is another very knowledgeable individual, and so is Tim Keith.

And of course the Grand Master George Asche  who built Don Coatneys intake and exhaust, and as well as mine.

So either George or Tim Kingsbury for the most on the most....

 

Edited April 14, 2017 by 55 Fargo Spitfire

[55 Fargo]

You want to see ultimate Chrysler Flathead performance, 265 racing hi perf engines.

 

 

 

[dpollo]

The 23 inch engine  was the first of its type to appear in 33 , modified with full water jacketing in 35 and used in Plymouth and Dodge through 59 , 60 in trucks and  72 in Power Wagons  .  The crankshaft was much improved for the 218 . The last 201 was phased out in  41.

The 230 was the largest of this series and all things considered, it was a very successful design and in sheer numbers dominated the field. Some speed equipment was available for the 25 inch engine . Edmonds being the most common. Many companies including Fenton and Tattersfield  made equipment for the 23 incher.

The 25 inch in engine appeared  in '37-8 to replace an over heavy design which was used in the Chrysler , It took its engineering cues from the 23 incher and for the most part, shared timing gears, front covers, fuel and oil pumps, bell housings and flywheels.  An engine plant was opened in Canada in 38 and the 25 inch blocks were used in all cars made in Windsor.  All displacements of this design on both sides of the border  shared gaskets, camshaft bearings and crankshaft bearings. Bores were 3 3/8 and 3 7/16 and strokes - 3 3/4. 4 1/16 ,4 1/4, 4 1/2 and 4 3/4. They were last used in passenger cars in  59, trucks in 60 and power wagons up to 72.  They were popular as industrial  engines as well.

If you really want to know how Chrysler's engines evolved, especially in the early 30s and again in the early V8 era, I recommend you read Willem L Weertman's book       Chrysler Engines 1922-1998 published by SAE      ISBN# 978-0 7680-1642-0

[meadowbrook]

 Thank you very much for the detailed history 

[desoto1939]

the book is on Epay for the very low low price of $138.00.  Hope he gets the asking price.

 

Rich Hartung

[DJ194950]

Wrong forum post.

Edited April 15, 2017 by DJ194950
Posted in wrong post.