1952 Plymouth Overdrive Upgrade questions.

[1952Cranbrook]

Hello all!

I have a 1952 Plymouth Cranbrook that I recently finished restoring and have been driving around. After getting it on the road, I quickly realized the draw of an overdrive transmission, which my calculations show would give an estimated ~20 mph increase in range.(Which would be basically necessary where I live)

 

I have had trouble finding an overdrive trans for a good price, it have recently found someone selling one nearby for $700. I was just interested if anyone was more knowledgeable about overdrives and could help give me some direction on exactly what needs to be changed, added, modified, etc.

I know I will have to modify the electricals, but I’m not completely sure of “what” and “why” past what I found in my manual. Also wondering if the transmission is a complete swap in, or if I will need to modify things like driveshaft length and things like that.

 

I am talking to the seller about looking at it and possibly purchasing it Saturday, so I would really appreciate any information, tips, and advice before then!!!

 

Thanks!!!

[pflaming]

$700 is a good buy. The r10overdrive will swap with the standard three speed. In short, no electricals are changed, you only add in the OD requirements. 
   It will transform your car. First a better top sped and a quieter car, then the huge benefit of 2nd gear over, especially in city driving.  There are some other details so I will let others address them.

   Attached is the schematic. 

Edited October 23, 2020 by pflaming

[Loren]

$700 is a good price. I paid $1,100 for mine. It had been rebuilt with a new 12 volt solenoid, a new 12 volt relay and a drive shaft.

There are several sources for wiring diagrams and service manuals, some free.

Do not take the short cut of an on/off switch. Your risking the destruction of a rare and expensive item. (don't ask me how I know)

The R10 Borg-Warner Overdrive is designed to be Automatic and it works very nicely that way. If you think your car has charm now, just wait!

The operation works like this: When you're in second or above and the Governor (a type of speed sensor) says its okay (the trigger speed is adjustable but don't worry about that) lifting the throttle slightly will allow the relay to interrupt the ignition (you'll never feel it) and activate the solenoid which shifts into Overdrive. It takes a little practice to activate in second gear and a certain type of road condition but high gear is easy and you won't even need to think about it. On the highway when you hit a hill which requires full throttle the throttle position will trigger a switch which shifts the Overdrive back into direct drive giving you power to pass or get up the hill without slowing. Once you crest the hill lift throttle and you're back in Overdrive.

 

Of all the cars that had Overdrives available to them, I think the Plymouth benefitted the most. Because Chrysler waited until May of 1952 to offer them, they are kind of rare. I really don't know why that is as the Chrysler engineers had plenty of experience with Underdrives in their semi-automatic transmissions.

Properly installed and functioning correctly an Overdrive will really improve your car. I once owned an International Travelall with a B-W T86 3 speed transmission and Overdrive which worked very well. I absolutely loved its operation! Plymouths are not race cars, they were meant to be sensible transportation and the Overdrive makes them even more sensible and pleasant to drive.

To install the transmission you will need a shorter driveshaft. That is not really as big a deal as you'd think. Every city I've lived in has a shop which specializes in driveshaft repair and modification. Talk to them before doing any engineering on your own.  Next be sure the parking brake is in good shape and adjusted correctly. You will need to be religious about its use! You can't just leave the car in gear when you park it...it will roll. The electrical hook up is very simple if you have the right relay and switch. Plymouth used a switch on the carburetor. If you don't have the bracket they are easy to make and certainly not worth what some people think they are. ( I've seen as high as $250 for a tiny piece of angle with three holes drilled in it! )  A lot of cars used a switch which came up thru the floor to the bottom of the throttle. I've had both and prefer the stock Plymouth set up. When I needed a switch I bought one from a guy on eBay who supplied them for Studebaker owners. Studebaker used a carburetor switch while Ford used a floor switch. The Carburetor switches are much smaller so they will fit and that's the identifier.

I can not stress this enough, install the Overdrive as designed with throttle switch and relay. The cable control to lockout the Overdrive is optional only because not having it will not destroy the Overdrive. Its for push starts and parking on hills with an "iffy" parking brake. Once you've used one that's properly set up you'll never consider anything less.

[Young Ed]

Not true on driveshaft unless he has a short wheelbase p22(which from the pic he doesn't). 

[Loren]

I've seen so many variations in Plymouth tailshaft length that I always assume the driveshaft will need work.

My 52 Suburban transmission had a very short tailshift and the Overdrive transmission I got for it was from a 52 Suburban as well, came with the driveshaft.

Better to be warned unnecessarily than to be surprised later on.

Also its a good opportunity to upgrade the U-joints to Spicer type with a slip joint at one end. When you do that the shop usually just makes you a new driveshaft.

[Ernie Baily]

Hello,  When I did my overdrive change I used one out of a 53 Plymouth. The length of the trans or my 1948 Plymouth was the same as the 53 Plymouth overdrive R10.  It just bolted right in. I was told to use a Plymouth OD into a Plymouth(mine is a 1948 Plymouth). the lenghts were more likely to be the same. The only thing to think about is the rear gear ratio, My 48 had a 3:91 which I left alone and the 53 Plymouth was 3:54. The 3:54 would have been better for highway driving with the overdrive.

Good luck with yours, mine had been working great for years.

[allbizz49]

Unless you're totally hung up on the r10, look into a t5 swap. I went back and forth for a while, mostly because I wanted to keep the column shift but went with a t5. Simple swap and pretty inexpensive. 

[The Way]

There is also the Mopar A833 swap. Tim Kingsbury has a blog regarding that in the blog section that is very informative. Robert Horne used a TK5 from a Ford Ranger. He takes you right through step by step. You do have choices, but, the R10 is certainly the easiest.

[Adam H P15 D30]

I found an R10 locally for $400.00, it's listed as a "core" but is complete.  Now that I'm thinking about it, I might just pick it up....

BTW, $400.00 is a really good price!

[1952Cranbrook]

Wow!

Thank you all so much for the wealth of knowledge!!! 
So if I had to put together a parts list...

 

1.Overdrive relay

2.Overdrive solenoid

3.Overdrive Kickdown switch
4 Overdrive governor

 

And possibly a lockout rail?

 

Also, forgive my lack of knowledge, but are some of these parts already included or integral to the O/D transmission?

 

Also here are the pics of the numbers on the OD trans: from a 1955 Plymouth.

[1952Cranbrook]

Also, for the parts I need to acquire, where do I find relays and solenoids? 
Do I need to find an aftermarket/modern relay that just matches the specifications? Or do I need to find an original Mopar relay? Same with the switch? 
 

 

[Booger]

3 minutes ago, 1952Cranbrook said:

Also, for the parts I need to acquire, where do I find relays and solenoids? 
Do I need to find an aftermarket/modern relay that just matches the specifications? Or do I need to find an original Mopar relay? Same with the switch? 
 

 

Jump on it NOW

[Booger]

50 years ago I bought a R10 for $75 and its bolted right up to my first P18. I ran a choke type cable under the dash and that was it to engage the OD

[kencombs]

15 minutes ago, 1952Cranbrook said:

Also, for the parts I need to acquire, where do I find relays and solenoids? 
Do I need to find an aftermarket/modern relay that just matches the specifications? Or do I need to find an original Mopar relay? Same with the switch? 
 

 

Governor and solenoid should be part of the of trans

[Go Fleiter]

-My OD had to come with another gearbox. The transmission needs a hole for the shiftrail.

-The funktion of the kick-down- switch is much too crude for my feeling!

-I use the OD- engaging cable and handle because letting engaged the OD You will have free wheeling under 30 mph (disengage speed off the governor switch).

I do´t like free wheeling and use a handswitch instead.

-the propellershaft was unchanged in my P23/1951 covertible

-I like most the rpm reduction of the overdrive, it turns 2100 rpm at 140 kmh = 87 mph (depends on rear axle ratio) - very comfortable for the engine, but not for the driver:  the chassis is not made for these speeds as aren´t the brakes.

But for long holiday travels, the OD is perfect! I got mine from George Ashe´s - yes, expensive, but he even let me choose a "faster" second gear, which too is very useful if not in the mountains.

Fotos: choose "about me":

https://p15-d24.com/profile/379-go-fleiter/?tab=field_core_pfield_18

Greetings from Düsseldorf! Go

 

here I fixed the OD- cable with longer heater bolts and a clamp on the heater fixing hardware - no holes needed to be drilled!

 

 

Edited October 23, 2020 by Go Fleiter
postig escaped before beeing comple

[Booger]

43 minutes ago, Adam H P15 D30 said:

I found an R10 locally for $400.00, it's listed as a "core" but is complete.  Now that I'm thinking about it, I might just pick it up....

BTW, $400.00 is a really good price!

If you dont want it Ill take it. Go 9ers

[Sniper]

Moparpro has a used one listed as parts only for a crazy price then there is another guy that has one he thinks works but hasn't tested it for over $2k, both on ebay

 

jump on that $400 unit or we'll see him get it and relist for triple that, at least.

 

Me?  I already have two good A833OD's on the shelf.  Thinking about the adapter someone mentioned.

[The Way]

George Asche is a great resource for information on R10s and may even sell you any parts you need. He does not use the internet at all, his number is 814-354-2621. His boys (George Jr. and Rob) are quite familiar with them as well

[Young Ed]

5 hours ago, Loren said:

I've seen so many variations in Plymouth tailshaft length that I always assume the driveshaft will need work.

My 52 Suburban transmission had a very short tailshift and the Overdrive transmission I got for it was from a 52 Suburban as well, came with the driveshaft.

Better to be warned unnecessarily than to be surprised later on.

Also its a good opportunity to upgrade the U-joints to Spicer type with a slip joint at one end. When you do that the shop usually just makes you a new driveshaft.

I believe all the column shifted 3 spds are the same length with the exception of your short wheel base cars. Why they shortened the trans vs the driveshaft IDK.... Dad and I even swapped an OD into a 51 dodge in place of the gyromatic and that didn't require driveshaft mods either

[Adam H P15 D30]

Here it is guys and gals....  I'm not cutting my brand new driveshaft.

https://sfbay.craigslist.org/pen/pts/d/menlo-park-chrysler-dodge-hemi-c/7203882881.html

[Young Ed]

4 hours ago, Adam H P15 D30 said:

Here it is guys and gals....  I'm not cutting my brand new driveshaft.

https://sfbay.craigslist.org/pen/pts/d/menlo-park-chrysler-dodge-hemi-c/7203882881.html

Not sure what car you'd be putting it in but likely not driveshaft mods needed

[Adam H P15 D30]

26 minutes ago, Young Ed said:

Not sure what car you'd be putting it in but likely not driveshaft mods needed

My Wayfarer uses the stubby transmission 

[derbydad276]

I'm picking up one tomorrow for my Dodge ... & I'm hoping it wont be too hard to make a plymouth trans work on a dodge 

evidently the dodge bell housing is a deeper depth for the fluid drive that I dont have  

[woodie49]

I put a '53 OD unit in my '49 Plymouth Woodie. Everything bolted right in, I did not need to change the drive shaft.  the linkage all worked fine. My unit came with the OD solenoid, but I have seen OD units offered without them.  

You will need an OD cable to put under the dash to turn your unit "off" and "on". That allows you to lockout the unit when you don't want it, like maybe a very hilly area where you want the trans to help you slow down. The cable goes down to the OD part of the trans . Usually this will be in the "on" position, which is fully pushed in. then the unit operation is essentially automatic.  The lockout in inside the trans, if you have an OD, you should have the lockout. You will need a governor, which will most likely come with the trans. It controls when the unit energizes the solenoid to allow the shift into OD.  You do need one, I am not aware of any workarounds for it.. You will need an OD relay.  Mostly this does not come with the unit, if it does, its a great deal. If it doesn't, you can use a substitute relay that will plug in under the dash for very little money. You can get the kick down switch if desired.  That sits at the carb and grounds your OD circuit temporarily stall the engine and allow the OD to drop out for hard accelerating.  I chose not to use this.  Instead, I have a switch under the dash that I can use to ground the circuit and then when i let off the gas, the unit shifts out of OD.  When I engage the unit through the switch, it just closes that part of the circuit so that when the governor closes the points to actuate the solenoid, the unit will shift into OD. I prefer this to the kickdown switch.  This set up will not risk damaging the transmission as you might using the cable to "turn off" the unit.

 

You will need to create a small wiring harness for the unit.  I am not good with auto electrics and i got it done, so really anyone can.

 

If you don't get the relay with the trans, PM me and I can send you the info for the work around I used (assuming you leave everything 6 volt).

 

Probably one of the best upgrades you can do for drivability and enjoyment.  You can keep up with traffic and not worry that you are redlining an 80 year old peice of machinery. 

[DJ194950]

Easily setup operation with 12 volt is doable.

 

One part I found that was needed was a 12 volt solenoid which was used on many brands ot cars that got a BW OD of similar style. Off and on many are on EBAY.

 

Others have said in the past the 6 v. solenoid works on 12v also , I found that I blew fuses quickly so I bought a 12v. on eBay with no problems.

 

New also available but $$.

 

Use a 12 relay for activation.  The governor if used does not care about voltage neither does a kickdown switch or toggle switch to take out of OD or engage it.

 

DJ