Technical Ply-Do inline6 - somebody out there ?

Just curious how you could swap a 25” head onto a 23” block...

 

I think you missed the “long headed motors” were swapped, not just the head.

 

Two different motors. The length of the heads is the most simple way of determining which motor you have.

Need to read the entire post, not just pick a line or two out of it. I stated which cars the different motors originally came in, and which parts were different between the two motor versions.

 

I always thought Plymouths and Dodges had the 23" motors, while Chryslers, DeSotos and M***ey-Harris had the 25" motors.

 

Don't forget the Parrett Tractors as well.

 

Then for whatever reason, all Mopars going to Canada had the 25" motors .... Not sure about other countries.

There is a very heavy horseshoe mount the radiator bolts to. The mount has captured nuts installed for the radiator to bolt to.
From the factory the horseshoe mount has the captured nuts on front & rear side for either motor.
My truck is bolted to the rear of the mount for a 23" motor, if I remove the top sheet metal that acts as a shroud to guide the air .... I can move the radiator to the front of the mount & install a 25" motor.

While my 1/2 ton truck comes with 23", the bigger trucks using the same cab/body used 25" motors.
I believe the 1/2 ton Canadian trucks used 25" motors .... I'm sure there is more to it then just moving the radiator, but all Dodges were capable of running a 25" from the factory.

 

I'm talking domestic cars here. I have a friend who inherited a very nice '48 Dodge from his uncle who bought it new. He says it has a 230 ci 23" engine (he should know because he's searching for a finned head to go with his dual carbs and split exhaust).

 

The 217 (23” head) was used in ‘48-‘53 Dodge B and C series truck.
The 230 (23”head) in larger series trucks: D, Power Wagon, and E series.
The 250 (25”) in the F, G, H. Models.
265 in the J, K, models.

It seems there was a lot more speed parts available for the 23” motor, to me, at least when I was trying to find them for my 250.

 

If I remember correctly the mounts for the rads just had to turned backwards and upside down and you were good to go...

 

Well if I saw that I wouldn’t have posted what I did. I went back to try to find it but no luck. No matter... all is good.

 

Look at the last sentence of Genes reply

 

Take a close look at the 'horseshoe' holding the radiator and supporting the front fenders.
I the case of my 40 Plymouth coupe, it is tapered and has a round strut riveted to the front.
Removing the strut would allow the radiator to move forward, but the radiator still wouldn't fit inside the narrower front opening. This is online, but matches mine.

 

The "horseshoe" had different forms between the cars and the trucks, and even between the different truck time frames. The 39-47 truck horseshoe was different then the 48-53, and the 54 to 56 was also different. The car horseshoes shapes also changed through the years.

 

The P15-d24 group is the most active I believe. Use the search engine for good discussions.
George Ashe is a great reference.
Mopar Montana is worth a look.
Roberts has a good parts inventory as does Kanter.
There is a good deal of information out there and (go fast?) parts available.
There was once a parts company called Plydo. I still have an old catalog. They closed down several years ago and I have not seen them resurface.

 

A quick search on the 230 shows it was available in 1942 .... So no surprise the buddy has one in a 1948.

Just pisses me off because I have a 1950 & still a 218

The 230 shares the same engine block as a 218, it is simply a stroked 218 with different crank & rods.
Makes it wind up a little faster with some extra horse power. 105 hp instead of 100.

My only point in my post was a blanket statement that all Dodges came with a 23" motor is not true.
Most of them did, but to find one with a 25" motor would not surprise me one bit.
Especially the closer you live to the Northern border .... or one that is not original.

Finding a 1948 with the original motor installed might be more unusual then finding one with a 25" motor installed.

While that would work fine, it would move the radiator forward into the horseshoe bracket.

In my photo above I show a after market custom aluminum radiator painted black.
The original radiators the mounting bracket is brazed to the radiator.
I cut my original bracket off from original radiator, then cut each side to length & drilled holes in it to work with the $50 used radiator I bought off of facebook ...... Just saying it would be a lot of work to remove the original brazed bracket from the radiator & turn it around & braze it back on.

The 2nd issue I have with that is, why would the factory supply captured nuts on the mount to bolt the radiator in either position?

Just easier to modify the sheet metal shroud & move the radiator forward then it is to rework the radiator mounting bracket .... either would work.

 

I think we disagree on what the horseshoe mount is.
I say the horseshoe mount is the 1/4" C channel the radiator is bolted to, also the fenders & complete front sheet metal. It is a major structure of the vehicle.

What I'm looking at in your photo I think you are showing a sheet metal cap that is bolted to the horseshoe mount. If you were to remove the bolts in green you could remove the cap ... might be a few other bolts to go with it.

Remove the cap, move the radiator forward .... now you need to deal with the cap.
My truck I can modify it & make it work .... your 40 not so easy.

A member on the forum has a 1938 Chrysler with all the bells and whistles, and a plane Jane 1938 Plymouth. He lives in Canada & both have 25" motors .... He had a 50's Dodge with a 25" motor ... he sold it.

I'm certain it was common to find a 25" motor in these old cars, I also believe the factory supplied different sheet metal to fit them. Depending what engine was going in.



I'm just saying, back in 1938 they were building these cars on a ***embly line .... they installed the correct parts depending on where the car was being sent.

 

The 40 in my garage has a complete loop, not a top and bottom. this supports the front sheetmetal and surrounds the radiator. If the side brackets for the radiator were removed AND the strut in the front of the loop were removed, the radiator still would be too wide to move forward and fit in the narrower front section. I plugged in an old hard drive and found this pic I saved of a car for sale years ago.

THIS ebay ad shows a similar loop
https://www.ebay.com/itm/115815966219
However, this one is straight walled front to rear, the 40 is tapered.

I read here and in other places about the 'flip it around' and 'change mounts' for more clearance when swapping the longer flathead and V8s. Looked very hard at options for my 40, and it wouldn't work that way. I would love to have that option, instead of the pusher fan I am planning. Don't live near Canada, so have not experienced a Plymouth stock with the long motor.

 

Well I found that “last sentence” and I’m dumbfounded how I misread it. Possibly the pain killers... My experience has been with my ‘42 Fargo p/u. As far as engine size goes all blocks in CDN vehicles were 25”, at least for cars and light trucks not including the I8’s. The blocks were cast in Windsor, Ontario so they were not going to cast the shorter blocks nor import them, due to tariffs.

 

I do have an Ellis intake for two carbs and the B&B carbs. Now I’m thinking the Chevy carb option....

 

No reason to argue over things .... Red is where the 23" radiator bolted to, blue is where it was for a 25" engine. .... Thats a 2" wide mount.



If you go to this video then freeze it at 9:12 you will see the Chrysler had a very wide sheet metal enclosure and the radiator cap came up through the middle of it.


I'm just saying that Chrysler, Plymouth, Dodge, Trucks ..... they all moved the radiator 2" differently ... but they all moved them to install a 25" motor.

 

Back in the late fifties though the mid 60's one of my uncles drove and early 50's Dodge Suburban with what he called a Chrysler Big six in it with a Dodge truck granny 4 speed. With six ply tires on the front and fairly agressive snow tires (Grips in Texas) on the rear that old thing would climb a rock wall. It wasn't fast on the road but would grunt up and down mountain roads pretty well. I don't think that my back ever recovered from changing the clutch in it one fall before hunting season either.

 

Not to complicate this more, but on my ‘46 Plymouth it was pretty easy to move the radiator forward as the sheet metal was already relieved for it.

 

This wakes up a stock 230.

 

Looks great, too. God Bless Eddie Edmunds.

 

Actually the 25 inch motors were mostly used in Canada. My 46 Dodge 3/4 ton has a 23 inch motor. All the 201, 218 and 230 motors are 23 inch.

 

Careful, there is a 218 in 25" North of the border....

 

You are correct. I wasn't clear that I was talking in the US.