Block size question????

[CO54]

So we know there are 2 sizes to the Dodge engine blocks.  23" and 25" what is the determining point?  If measured from the head I have a 23", when measured from the oil pan I have a 25"?  Which is it????  The block casting # is T334*I954........

 

[Plymouthy Adams]

the head should be your reference point.....

[CO54]

Just to clarify, the head mounting surface correct?

[JBNeal]

additional information - Flathead Six Engine Numbers 

[Dodgeb4ya]

7 hours ago, CO54 said:

So we know there are 2 sizes to the Dodge engine blocks.  23" and 25" what is the determining point?  If measured from the head I have a 23", when measured from the oil pan I have a 25"?  Which is it????  The block casting # is T334*I954........

 

There are three lengths of Dodge engines...add the 30" engines found in the Heavy Series Dodge trucks through 1956.?

[Charlie Stephenson]

Yes 30". A 413 cid would be nice to own.  Charlie Stephenson

[Dodgeb4ya]

20 hours ago, CO54 said:

Just to clarify, the head mounting surface correct?

That's  the correct way as mentioned.

[CO54]

Thanks for the input gents.  With the link provided by JBNeal..... I see that I have a 218 or 230 based on numbers I see, how do you tell if the block is a 218 or 230?   Please advise. 

Thanks. 

Eric

[Merle Coggins]

218 and 230 blocks are virtually the same. The difference is in the stroke length. So you have to measure the piston stroke to determine the displacement. 

[Plymouthy Adams]

for a bit of added info...measuring the stoke is done at #6 cylinder and you will find a removable plug in the head for insertion of a device to measure the stroke...many use a steel rod, round wooded dowel etc ...

[tom'sB2B]

218 23" vs 265 25"

[Pete]

Just to confuse the issue -- in 1937 & 38 Dodge put 216 25" blocks in their half, 3/4, and one ton trucks. That's what I have in my 38 RC, and the build card says it's original to the truck.

Pete

 

[ggdad1951]

15 hours ago, Merle Coggins said:

218 and 230 blocks are virtually the same. The difference is in the stroke length. So you have to measure the piston stroke to determine the displacement. 

 

IF I remember right (big if), the block PN was the same in the parts book when I looked a few years back.

[CO54]

With the head already off, along with all other bolt on items, is there a way to measure the stroke and get the info needed from the deck as a reference?  Is there a difference in the connecting rod or the crank that could be identified with a PN# for example?

What would be the difference in the stroke length?

Edited December 30, 2019 by CO54
typo

[ggdad1951]

you could still measure stoke, just need to add the head thickness, and or someone might have the difference with out the head.  The crank and connecting rods are different PN's.

 

 

[Plymouthy Adams]

the stroke can be measured 15 foot away if you have a 15 1/2 foot rod....stroke is the travel of the piston top from one extreme to the other...any other measurement is also static to whatever gauge point you use...head on or head off...head off allows for the actual 'below deck' measurement if needed...

 

218 has 4 3/8 stroke

230 has 4 5/8 stroke

Edited December 30, 2019 by Plymouthy Adams

[CO54]

23 minutes ago, Plymouthy Adams said:

the stroke can be measured 15 foot away if you have a 15 1/2 foot rod....stroke is the travel of the piston top from one extreme to the other...any other measurement is also static to whatever gauge point you use...head on or head off...head off allows for the actual 'below deck' measurement if needed...

 

218 has 4 3/8 stroke

230 has 4 5/8 stroke

Perfect, Thank you!!