Is a front suspension swap from 48 Plymouth to 52 Chrysler New Yorker possible?

[52Yorker]

Hello all,

I 'race' a 1952 Chrysler New Yorker (originally a 331 V8, Now has a 413 RB / 727) in the 24 hours of LeMons, our car has 4 wheel drum brakes which are simply not adequate for racing and need to be swapped for disc brakes ASAP. We are focusing on the front disc swap at this time. 

Another LeMons team is racing a 48 Plymouth that already has an 'Explorer' disc upgrade, and are currently in the process of upgrading their front end again, thus their disc brakes and the complete front end have become available to us. I am trying to figure out if the Plymouth parts can bolt up in place of our New Yorker parts.

My Short question is 'Can I unbolt my New Yorker front suspension and bolt up the Plymouth suspension?'

Long question is a little more involved as what I've been able to gather from looking at the catalog at www.oldmoparts.com is that the New Yorker with a V8 may have different as in 'heavier' spindles, drums, etc... New yorker has a 5x5.5 wheel bolt pattern vs the Plymouth with the explorer disc brakes seems to have a 5x4.5 lug pattern.  The difference in part numbers makes me think that I cannot just move over the hubs. I'm hoping to be able to move over the upper and lower control arms with the spindles, etc...  

I am located in Maine and the parts are halfway across the country, need to figure out if this is possible prior to making a trip or shipping. 

Any advice is much appreciated. 

Attached pictures are the new yorker on track Loudon, October 2016 , Plymouth currently in pieces, and plymouth disc brake front end parts that are available to us. 

Dale.

Edited March 27, 2017 by 52Yorker

[knuckleharley]

Is that supposed to be an original P-15 chassis and front crossmember? It's dark outside now so i can't look at my P-15 sedan parts car,but that sure looks to be awful heavy duty for a P-15.

[52Yorker]

To my knowledge, yes it should be.

[Andydodge]

That P15 chassis looks stock to me apart from the front shock relocation........I have no direct experience with the 52 Chrysler chassis & front end but the suspension pivots, arms etc are supposed to be bigger, wider, longer etc however if it were me I'd try & get the Plymouth parts & do a direct physical comparison as even tho parts books etc may say that the Chrysler stuff is not an interchange it maybe possible to fit them with minimal fiddling, ie, I'd check whether the lower inner pivot pins and the 4 bolts that attach them to the front crossmember are swappable, maybe the Chrysler pins in the Plymouth arms and a similar arrangement for the top arms..........also whether the spindle and/or stub axle may swap.....if not will the Plymouth stub axle take a bore out to allow the Chrysler bushes & kingpin to fit it on the Chrysler spindle.........doesn't the 52 Chrysler have a drag link/bellcrank steering setup to reduce the Plymouth/Dodge bump steer from their short/long tierods?.............will this have any effect?..........anyway short answer to your short question is can you measure the distance between the 4 upper inner pin bolts and the 4 lower inner pin bolts.........I have Plymouth parts I can measure to compare..........Andy Douglas    

[Andydodge]

Just went & measured the Plymouth upper & lower inner pins..........the upper which uses 4 bolts to attach to the chassis is 2 & 5/8th" between the centre of the 2 holes on each side ..............the lower inner pin also uses 4 bolts, 2 on each side and its 7&1/4" between the centre of the 2 holes on each side..........these upper arms are 1941 but they are the same up to 1954, the lower arms are 1940 but diamensionally are indentical & interchange up to 1954 except where the front sway bar mounts, the arms themselves, upper and lower will bolt on 1940 to 1954..........hope this helps............andyd 

[52Yorker]

3 minutes ago, Andydodge said:

That P15 chassis looks stock to me apart from the front shock relocation........I have no direct experience with the 52 Chrysler chassis & front end but the suspension pivots, arms etc are supposed to be bigger, wider, longer etc however if it were me I'd try & get the Plymouth parts & do a direct physical comparison as even tho parts books etc may say that the Chrysler stuff is not an interchange it maybe possible to fit them with minimal fiddling, ie, I'd check whether the lower inner pivot pins and the 4 bolts that attach them to the front crossmember are swappable, maybe the Chrysler pins in the Plymouth arms and a similar arrangement for the top arms..........also whether the spindle and/or stub axle may swap.....if not will the Plymouth stub axle take a bore out to allow the Chrysler bushes & kingpin to fit it on the Chrysler spindle.........doesn't the 52 Chrysler have a drag link/bellcrank steering setup to reduce the Plymouth/Dodge bump steer from their short/long tierods?.............will this have any effect?..........anyway short answer to your short question is can you measure the distance between the 4 upper inner pin bolts and the 4 lower inner pin bolts.........I have Plymouth parts I can measure to compare..........Andy Douglas    

I will get to the New Yorker in the morning and take some measurements of the upper and lower pin bolts during daylight.

If the pivot pins share a bolt pattern where they connect to the crossmember, that gives me hope that the entire assembly would be able to swap over. If the stub axle will swap or is able to be bored, that would also be acceptable. 

The 52 does have a bellcrank. I am actually using an Astro van power steering box mounted on a plate welded to the frame as the original massive power steering box did not fit with the 413 RB mopar. I'm willing to fabricate whatever is needed to make it work, so long as I can make it with a grinder and a stick welder. 

Thank you very much for taking the measurements, That is very helpful, I've got a few feet of snow to clear off the New Yorker before I can measure in the morning. 

Dale.

[Andydodge]

Sno..? whats that?.......lol........its a pleasant 94F, a week ago was 105-110...lol..........even if the pivots bolt holes don't match maybe an adaptor plate bolted to the chassis holes at the top with countersunk cap screws then drill/tap the plate to suit the Plymouth inner shaft bolt pattern and similar on the bottom............this type of modification/adaption is the type I like, lateral thinking at its best........let us know how it goes........I actually checked both the Glenns and Motors Repair Manuals thinking that they may have to measurements but no luck there..........pleased that you understood my convoluted gobbledegook............lol.........regards, Andyd  

[knuckleharley]

5 hours ago, 52Yorker said:

I will get to the New Yorker in the morning and take some measurements of the upper and lower pin bolts during daylight.

If the pivot pins share a bolt pattern where they connect to the crossmember, that gives me hope that the entire assembly would be able to swap over. If the stub axle will swap or is able to be bored, that would also be acceptable. 

The 52 does have a bellcrank. I am actually using an Astro van power steering box mounted on a plate welded to the frame as the original massive power steering box did not fit with the 413 RB mopar. I'm willing to fabricate whatever is needed to make it work, so long as I can make it with a grinder and a stick welder. 

Thank you very much for taking the measurements, That is very helpful, I've got a few feet of snow to clear off the New Yorker before I can measure in the morning. 

Dale.

Probably the easiest way to see if this stuff is a direct swap is to check a Hollanders Interchange Manual.

[greg g]

There has been some discussion here about drilling brake drums.  This was a practice used by folks to improve braking performance of cars entered into events like the Mexico Road races and Carrara Pan Americana before the introduction of disc brakes.  Lots of Chrysler's rasn in those races. The process was also used in roundy round racing where upgrading systems with later components was prohibited by the rules.  The enemy of drum style brakes is heat or rather the shedding of it.  This drilling process directly vented the friction material contact surface.  In addition to heat dissipation, the process provides a path for the gases that forms as friction material heats and degrades to escape removing the cushion that may form resisting full contact.  Before you strip out the front end, it might be worth giving this technique a try to see ITF it makes a change in effectiveness of the drums under racing demands.

 

http://www.chtopping.com/CustomRod4/

Edited March 27, 2017 by greg g

[OnkelUdo]

Greg,

There is no way to use the factory size drums in the type of racing Dale is talking about unless you are content just driving on the racetrack while others race around you.  Thought this is great for winning the highest prize, the Index of Effluency, it is normally only fun once.  Most of the tracks  have an average of 4-5 turn per mile so you are constantly on the brakes or full throttle.  At 1:15 minute a mile you are talking about 330 braking events per 7-hour day...two days in a row

Everybody,

I have a separate thread about our race-proven 1948 Plymouth and we are the ones hoping to help Dale out with our Explorer conversion.  We are moving to a Crown Victoria front subframe so all the beautiful (as in ugly but functional) fab work did for the front brake conversion would likely go to waste otherwise.  The brakes were phenominal (as was the rest of the car) with barely measurable wear on the Raybestos ST47 pads after about 18 hours.  Granted, we almost had a problem keeping the pads up to temp (need to be about 200-250+ degrees to be linear) since we were only running the stock flathead but with the New Yorker's extra heft and power, that should not be an issue...especially keeping the rear drums.

[52Yorker]

9 hours ago, Andydodge said:

Sno..? whats that?.......lol........its a pleasant 94F, a week ago was 105-110...lol..........even if the pivots bolt holes don't match maybe an adaptor plate bolted to the chassis holes at the top with countersunk cap screws then drill/tap the plate to suit the Plymouth inner shaft bolt pattern and similar on the bottom............this type of modification/adaption is the type I like, lateral thinking at its best........let us know how it goes........I actually checked both the Glenns and Motors Repair Manuals thinking that they may have to measurements but no luck there..........pleased that you understood my convoluted gobbledegook............lol.........regards, Andyd  

Just took some measurements, Since my car is assembled and under 'snow', actually Ice at this point... it is a bit difficult, but I am getting very near the same measurements that you are. Didn't upload pictures of the lower mounts as they came out dark, and I was having to 'eyeball it' from above,  but I was getting very close to what you had. 

@greg g Thank you for the idea, I wish I had known about that prior to our first race. I donated the drivetrain to the project and someone else brought the car, I ended up owning the whole thing in the end.  Since we had massive brake fires, I'd need to replace all the rubber lines, wheel cylinders and shoes again which lasted less than 77 laps at Loudon. Literally had a line explode and a wheel bearing was flowing bubblin crude like it was 0 weight oil. Some of the hardware may be salvageable, but the majority of it I'd wager is going to be trash once it comes off the car. Passenger side front took the worst of it. Because I have no choice but to spend monies on it, I'd rather go with the disc conversion. I know I can make my own brackets and get a 5x5.5 rotor and caliper from a dodge ramcharger that will fit the new yorker, etc... but if I can adapt the plymouth suspension with their already complete conversion, I'd like to try. This is LeMons racing after all. 

[52Yorker]

8 minutes ago, OnkelUdo said:

Greg,

There is no way to use the factory size drums in the type of racing Dale is talking about unless you are content just driving on the racetrack while others race around you.  Thought this is great for winning the highest prize, the Index of Effluency, it is normally only fun once.  Most of the tracks  have an average of 4-5 turn per mile so you are constantly on the brakes or full throttle.  At 1:15 minute a mile you are talking about 330 braking events per 7-hour day...two days in a row

Everybody,

I have a separate thread about our race-proven 1948 Plymouth and we are the ones hoping to help Dale out with our Explorer conversion.  We are moving to a Crown Victoria front subframe so all the beautiful (as in ugly but functional) fab work did for the front brake conversion would likely go to waste otherwise.  The brakes were phenominal (as was the rest of the car) with barely measurable wear on the Raybestos ST47 pads after about 18 hours.  Granted, we almost had a problem keeping the pads up to temp (need to be about 200-250+ degrees to be linear) since we were only running the stock flathead but with the New Yorker's extra heft and power, that should not be an issue...especially keeping the rear drums.

@OnkelUdo, Not sure if I got to share the tale of how we discovered that the rear drums need the rivets otherwise it is no longer hubcentric. We couldn't get a puller to pull the hubs off in order to service the rear brakes, so the rivets got cut off and subsequently we were driving for a short time on 'square wheels' This caused some overheating issues and a radiator to explode. 

That rear end is coming off the car and will be replaced with a limited slip rear before it hits the track again. We used the intermediate driveshaft from the motorhome that donated the engine, so moving over to something more modern won't be too big of a deal. I like the explorer rear idea as it would match the fronts if they fit, otherwise I have a dana 60, a dana 35 and a chevy 14 bolt available.

I'm pretty okay with the stick welder, getting better every time the tractor breaks something,  so no worries about cutting and moving the parts for fitting up an explorer rear axle when I can find one.
 

[OnkelUdo]

I think you will find the Explorer rear to work unless your axle is significantly longer than the Plymouth.  The explorer axle is about 1" narrower (from memory) and the 3.73 Trakloc is about the most common disc brake explorer in the Midwest as it was kind of the default on V8's and the Eddie Bauer trim.  The only thing you have to do is swap or fab the spring perches and get longer u-bolts.  In our case the shocks even mounted up.

Do consider lowering it about 2" in the rear immediately.  Also, the 16" Explorer alloys from the stick-axle era are about perfect needing only about 1" spacers in front and 1/2" in the rear (longer studs needed for the rear and adapters with lugs in the front).  Crown Vic post 2002 should work as well but will need a deeper spacer as will the wheels from the IRS Explorers.  We are going to mount the Explorer sway bar in the rear but did not do so in the first race.

Edited March 27, 2017 by OnkelUdo

[52Yorker]

On 3/27/2017 at 7:05 AM, knuckleharley said:

Probably the easiest way to see if this stuff is a direct swap is to check a Hollanders Interchange Manual.

Got ahold of a hollanders interchange eBook but it does not seem to have the information I am looking for. Good to have otherwise though. 

From what I can tell thus far, the mounting locations on the frame appear to be in the same spots with the same bolt pattern and take the same size studs. The parts that bolt to the car are just physically larger but use the same mounts. This gives me hope that we can swap over the entirety of the suspension components.  At this point we are trying to find people to help use relay the parts from Michigan to Maine 

I thank you all dearly for sharing your wisdom. 

Dale.

Edited April 1, 2017 by 52Yorker

[classiccarjack]

If it works out, it will be great to know. Please post pictures if you get everything to bolt up and work out geometrically.

[52Yorker]

Quick update, 

We are planning to do this. The parts are enroute from Michigan to Maine now. Taking some time as people from LeMons racing community are helping to move them via relay system... No rush anyway as the weather here in Maine is still wintery. 

I will be sure to post as soon as we have results.

[Andydodge]

Pleased to hear that this possible swap is still in train............am looking forward to see whether its possible as I've wondered whether these type of swaps are possible.........am not surprised that the Hollander interchange book doesn't have this type of info as it seems to be a left field type of idea that the interchange books wouldn't have had to consider back then.........BTW...whos the dummy?......ME!!!.......guess what I remembered I had..........I just went & checked my 1950-1965 Chrysler Products Interchange Manual by Auto Interchange Systems dated 1965 and 1979 and while it doesn't have pre 1950 stuff listed and that's why I didn't check with it previously..........BUT I should have........it lists the SAME UPPER Control ARM PART for the 1951-54 Chrysler Sedans, coupes & converts BUT NOT wagons as that for 1951-54 DeSotos, 51-54 Dodge AND 51-54 Plymouth and I know for certain that 41-54 Plymouth upper A arms are the same part so I think that you maybe in luck..........lol.....lower arms for Chrysler, Desoto and Dodge cars, not wagons 1951-54  are listed as an interchange but NOT 49-52 Plymouth which seems an odd listing, later Plymouth lower arms aren't listed.........I wouldn't be surprised IF the actual Plymouth lower arms bolted on but had different sway bar and or shock mounting points which resulted in this listing variation.......anyway I had forgotten that I had this interchange manual so if you need anything checked let me know....this manual also lists PART NUMBERS as well........lol..........this was a 180 page book that  a mate had 30 yrs ago and let me photocopy.........lol............regards, Andy Douglas  

[bigdaisy19k]

Was http://rustyhope.com/site/ not an option for disc brake conversion?

[Andydodge]

Bigdaisy.....valid point but I think that there is a dollar limit or something like that which has precluded the spending and the various disc brake conversions don't list the 52 Chrysler as one of the cars that the conversions fit.........I think........andyd 

[52Yorker]

19 hours ago, Andydodge said:

 

8 hours ago, bigdaisy19k said:

Was http://rustyhope.com/site/ not an option for disc brake conversion?

There are options for a disc conversion bracket that I can bolt on, but they are expensive for just a set of brackets that I could essentially make myself.  I would also have to send them my larger sized spindles to have them turned down, and I'd need different hubs which would further increase the cost. This would still require me to go from a 5x5 bolt pattern down to a 5x4.5... 

If I were to use my existing spindles / hubs, I'd piece together and cut my own brackets to fit brakes off a mid 80's dodge, but there are uncertainties about the rotor / caliper offset.

 If the plymouth suspension bolts up, this will save me money (even though it has a smaller lug pattern and I'll need different wheels), and it will be a good way for the other team to be rid of their now unneeded disc brakes.  This also comes with some very expensive brake pads and all of it at a much cheaper price than I could possibly piece it together myself. Shipping will cost me a few lobsters and a trip from Maine to Mass. 

It also makes for a great story as it will certainly be featured on the 24HOL and several other sites if all goes as planned. All about the glory. 

1 hour ago, Andydodge said:

Bigdaisy.....valid point but I think that there is a dollar limit or something like that which has precluded the spending and the various disc brake conversions don't list the 52 Chrysler as one of the cars that the conversions fit.........I think........andyd 

This car is mostly exempt from the $500 limit as we aren't at risk of going fast or winning any races, and safety components are exempt from the dollar limit as well, so this could essentially not matter to the judges. They really are just happy to see us out there, even if we are mostly blocking traffic... However, I am not made of money and this is the cheapest way for me to get a disc conversion so that I can focus my monies elsewhere.  I still need to do a rear axle and leaf spring upgrade, rebuild the carb, pull the heads and lap the valves, make a new exhaust (it hits the ground when cornering hard), install a better steering column, and fix a few other deficiencies before the next race. 

I appreciate the information you got from the interchange manual, Once I have the parts on hand, I'll be able to tell where the differences are, and with any luck will be able to use mostly stock parts to make them fit up. 

Dale.


 

 

Edited April 23, 2017 by 52Yorker

[Andydodge]

Dale, no worries........am really looking forward to seeing how this goes.............Andy Douglas

[55 Fargo]

Just a FYI, I installed the entire front suspension from a 1951 Plymouth, smaller spindles, and 10 inch brakes on to my 1947 Chrysler, it bolted right up....

I have done this and know, do not see why it won't work for you, no point in others opinionating, wait and see, this should be no issues, but you never know.....

[52Yorker]

7 hours ago, 55 Fargo Spitfire said:

Just a FYI, I installed the entire front suspension from a 1951 Plymouth, smaller spindles, and 10 inch brakes on to my 1947 Chrysler, it bolted right up....

I have done this and know, do not see why it won't work for you, no point in others opinionating, wait and see, this should be no issues, but you never know.....

Very good to know that it worked for you.  You're the first person I have heard of doing this swap. 

Was your car a 6 cylinder or 8 cylinder? it seems that may be the major dividing line between them, but I suspect that the mounting locations will be the same and the v8 331 early hemi (long gone, now has a 413 RB / 727 Loadflite) that mine was originally equipped with may have necessitated the 'larger' components simply due to the weight difference.... 

 

dale.

[bigdaisy19k]

I know it's less expensive this way, but for safeties sake if you were my kid, I'd say keep your heavier duty components and find a way to afford scarebird or rustyhope parts.  They may love to see you out there racing, but there's likely other people who'd like to see you when you're done.  There I said my piece, I wish you good luck sir.

[52Yorker]

1 hour ago, bigdaisy19k said:

I know it's less expensive this way, but for safeties sake if you were my kid, I'd say keep your heavier duty components and find a way to afford scarebird or rustyhope parts.  They may love to see you out there racing, but there's likely other people who'd like to see you when you're done.  There I said my piece, I wish you good luck sir.

All things considered, this option is plenty safe as those other options require a different hub and turning down the spindle to the same size as what im going to put on..... Your anecdotal evidence is just that. 

If I wanted to keep the larger hub size, I could piece together a brake setup to fit my car but not using the components available on those websites. And I'd still be making my own bracket as theirs wouldn't fit any known caliper / disc options for a 5x5. 

If you were my kid, I'd tell you to go do your homework.