Hey guys, After reading this thread: http://www.jalopyjournal.com/forum/showthread.php?t=260795&showall=1 About using a current model coil spring (from a 1990 Ford Aerostar) to lower mid 50's Fords about 3", I'm trying to find the same alternative for our Plymouths & Dodges. I'm no expert on coil springs, but I believe I can figure out a good alternative...who knows, the same spring they talk about above might just work for us too, but I want to confirm it. What I need right now is the stock spring specifications for our 40s & 50s MoPars. I've looked through every catalog I can find, and cannot get specs on the stock springs....so come on, I know one of you guys has them! Then I'll find us an alternative current model spring to get us dropped down. Just for reference, here is the specs on the stock 50's Ford coil spring, and the Aerostar replacement for a 3" drop. All this info is from NAPA's catalog: Original Ford Spring: (note, their catalog also listed P/N NCP 2771156 as a replacement, which has slightly different specs) NAPA P/N: NCP 2771154 Cost: $99.49 # Coils: 10.09 Free Height: 16.44" I.D.: 3.63" Load Height: 11.13" Type: Two Tangential Ends Design Load: 1726 Spring Rate: 328 Wire Diameter: .625" 1990 Ford Aerostar (3.0 & 4.0 L engines) for a 3" drop: NAPA P/N: NCP 2775245 Cost: $73.49 # Coils: 7.28 Free Height: 11.65" I.D.: 4.07" Load Height: 10" Type: One Tangential End, One Square End Design Load: 997 Spring Rate: 605 Wire Diameter: .735" So I have some idea what the ratio of change should be from a stock spring to a 3" drop. So if you guys could help me out with the Stock MoPar spring specifications, I will get to work on this and find us a bolt on alternative to cutting coils! Evan
I'm also interested in this, and while I don't have the answers to the questions, I might have a useful clue or two: I have a page from a Moog Dodge application book (I assume 6 cyl Plymouth, Chrysler, and Desoto are the same in most cases) and that says the Moog part numbers for the springs for the springs are as follows: 1941-1951: #730 for all models except Conv. Coupe and Diplomat Wagon. Diplomat and Conv. coupe: #738. Heavy Duty applications use #813 (again except conv. & Diplomat). 1939-1940: #733 for regular, #730 for xs, #813 for heavy duty. Now if somebody just has the actual specs that go with those part #'s...
4woody thanks for the reply. I just need to find a cross reference from Moog P/N's to Napa P/Ns. Napa is the only place I've found with a fully accessible catalog to get all the part specs. Moog does not list their catalog unfortunately. Great clue though, thanks I'll see what I can find using that.
Hey how old are those part numbers? Do you know how old the book was you got them from? I don't see any MOOG P/N's that are 3 digits.
It is just a copy of a page someone sent me with some aftermarket forged upper arms I was going to use (Turns out '38 and '39/'40 uppers are different enough that I couldn't use them without major mods, but thats another story. Look for them in the classifieds soon...) Anyway, it looks like the page is from an early-50's book.
out of my shop manual: For models D-29, D-30, D-33, D-34, D-41, D-42 Springs Front: Type Coil Diameter (i.d.) 4" Static height 8 3/4" (except Convertible Coupe, Stationwagon, And 8 Pass.) Static height 11" (For C.C. Stationwagon and 8 passenger) That's all my book has. Doesn't even have part numbers as it was for "the Shop" and "didn't need" the part# as the tech worked at the place, walk in to the back and pulled the part.
Ok got an update. Here is the only list of Moog P/Ns & Specs I could find: http://bbb-carb.com/moog_Coil_Springs.htm Here are the applicable part numbers and specifications listed there. These numbers are only listed with a CC in front (which I've gathered seems to mean it was a variable rate coil spring...did these cars have that?) CC730D (I'm assuming Dodge?) I.D.: 6 Bar Diameter: 0.570 Install Height: 11.0 Load Rate (lbs): 545.0 Spring Rate (lbs/in): 91.0 Free Height: 17.0 Type: Tangential Ends CC730P (I'm assuming Plymouth?) I.D.: 6 Bar Diameter: 0.570 Install Height: 11.0 Load Rate (lbs): 505.0 Spring Rate (lbs/in): 91.0 Free Height: 16.56 Type: Tangential Ends CC813 (The heavy Duty springs referenced above) I.D.: 5.430 Bar Diameter: .640 Install Height: 10.75 Load Rate (lbs): 1000 Spring Rate (lbs/in): 182.0 Free Height: 16.25 Type: Pigtails
Can any of you guys confirm these measurements of the Moog P/Ns are reasonably close to the coils in your car? The thing I'm worried about is the MOOG #'s all have an I.D. of ~6", while as Jayne Cobb said the factory service manual said they should have a 4" ID? How much wiggle room do we have in the coil bucket and pocket to fit a larger spring? Comparing the CC730D to the Ford stock specs: ___________________CC730D (Mopar)________Ford I.D.: __________________6_________________3.63 Bar Diameter:___________.570_______________.625 Install Height:___________11________________11.13 Load Rate (lbs):_________545________________1726 Spring Rate(lbs/in):_______91_________________328 Free Height:____________17________________16.44 Type:_______________tang. ends____________tang. ends It looks like our ID's are much bigger, but will we be safe with a smaller ID spring (the Aerostar spring is 4.07" ID)? The heights look good, but the load rate & spring rates are much different. Looks like we're much lighter on the front end....The Aerostar spring will then probably give us the drop we need as long as the small ID is ok, but will be very stiff right?
I have a '50 Dodge Wayfarer. just went to the garage and checked the coils in the buckets, you are definently not going to be fitting 6" I.D. springs in there. Does anyone have their springs out of the car at the moment? that would help this research project greatly!
Ok thats good info. Can you measure or get a rough estimate of Inside Diameter of the coil? Can anybody chime in on the load rating & spring rate for the dropped spring. What will this affect exactly? Also, why are all these listed with the Inside Diameter spec'ed? It seems to me like the Outside Diameter of the coil would be more important right? Cuz we're not putting a shock through the middle of the spring, so who cares what the inside width is?
For a 50 Plymouth the measurements of a new set (from I think ESPO or Eaton) was 17 3/4" long, 3 7/8" I.D., and 5 1/4" O.D. FYI when I cut these to 12 3/4" (don't recall how many coils that was) it dropped the car 2 1/2" as measured at the frame near the lower A-arm. The I.D. matters because there is a piece shaped kinda like a top hat that locates the spring by fitting up inside it. You can barely see it in the center of the spring in this pic:
I just bought new lowering coil springs from jamco Suspension. They have 2" and 3" drop. Cost 80.00 plus ship. Real happy with them. Mopars Rock!!-Sololobo
i am goin to try to find wat i cut off my coil. i'm actually interested to figure this out. i chopped my coils and am lookn to get the front back up alittle. that is a bitchn price. i will do wat i can to find those specs asap.
Aren't you way over-thinking this thing? Just take them out and cut a freaking round out. Couple of hours, one hacksaw blade or a few minutes with a cut off wheel and your down three inches.
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