Please login or register.

Login with username, password and session length
Pages: [1] |   Go Down

Author Topic: Mopar leaf springs info  (Read 6008 times)

0 Members and 1 Guest are viewing this topic.

Bill55az

  • Dippy God
  • ****
  • Offline
  • Logan, UT and Peoria, AZ
  • Posts: 668
Mopar leaf springs info
« on: January 14, 2008, 10:47:14 »

Mopar Springs, front/rear/total dimensions
62-63                   20 35 55
64-65                   21 35 56
65-70                   22 36 58
70-74 E body        22 35 57
60-76 A body        20 35 55
71-74 B body        22 36 58  some 74 had 21.25 front segment, same rear segment.
All FMJ bodies      24 34 58
Dakota                 24 32 56
Super stock          20 36 56
Logged
1980 Diplomat coupe, slant 6

Dippy.org

  • Advertisement
  • ***

Reggie

  • Gran Fifthlomat Meister
  • Global Moderator
  • Dippy Oracle
  • *
  • Offline
  • Maryland - DMV Area
  • Posts: 5051
Re: Mopar leaf springs info
« Reply #1 on: January 14, 2008, 10:58:53 »

Mopar Springs, front/rear/total dimensions
62-63                   20 35 55
64-65                   21 35 56
65-70                   22 36 58
70-74 E body        22 35 57
60-76 A body        20 35 55
71-74 B body        22 36 58  some 74 had 21.25 front segment, same rear segment.
All FMJ bodies      24 34 58
Dakota                 24 32 56
Super stock          20 36 56

Great info BIll,

Double check the F/J/M front segment length though.  I don't have the Mopar Chasis Manual handy, but I think it is 34". 
I do know that the F/J/M front spring segment lengths are the longest of any Chrysler car built through 1989. - RR
Logged
"There is only one success - to be able to spend your life in your own way." - Christopher Morley 1890-1957, American author and editor

Library format and content © 2007- 2012 Reginald A. Royster, Sr., unless otherwise authored or noted.

Bill55az

  • Dippy God
  • ****
  • Offline
  • Logan, UT and Peoria, AZ
  • Posts: 668
Re: Mopar leaf springs info
« Reply #2 on: January 14, 2008, 11:05:38 »

no, 24 is correct, if someone has 34, it is a typo...
It is still the longest front segment, tho, except for front wheel drive minivans, which are  30 front 26 rear, and I suppose those could be used in reverse, or 26/30/56.
As far as I know, Mopar is the only car maker using short front, long rear segment dimensions.
Logged
1980 Diplomat coupe, slant 6

S-type

  • Dippy Oracle
  • *****
  • Offline
  • Posts: 3586
Re: Mopar leaf springs info
« Reply #3 on: January 14, 2008, 11:25:27 »

As far as I know, Mopar is the only car maker using short front, long rear segment dimensions.

Thats correct, anyone know why they did that? A very good reason only a gearhead would love.
Logged

Reggie

  • Gran Fifthlomat Meister
  • Global Moderator
  • Dippy Oracle
  • *
  • Offline
  • Maryland - DMV Area
  • Posts: 5051
Re: Mopar leaf springs info
« Reply #4 on: January 14, 2008, 11:38:36 »

no, 24 is correct, if someone has 34, it is a typo...
It is still the longest front segment, tho, except for front wheel drive minivans, which are  30 front 26 rear, and I suppose those could be used in reverse, or 26/30/56.
As far as I know, Mopar is the only car maker using short front, long rear segment dimensions.

OK thanks for typing it up. :thumb:  - RR
Logged
"There is only one success - to be able to spend your life in your own way." - Christopher Morley 1890-1957, American author and editor

Library format and content © 2007- 2012 Reginald A. Royster, Sr., unless otherwise authored or noted.

Bill55az

  • Dippy God
  • ****
  • Offline
  • Logan, UT and Peoria, AZ
  • Posts: 668
Re: Mopar leaf springs info
« Reply #5 on: January 14, 2008, 11:45:34 »

As far as I know, Mopar is the only car maker using short front, long rear segment dimensions.

Thats correct, anyone know why they did that? A very good reason only a gearhead would love.
Saves money, no need for extra location stuff to keep the axle in place during hard acceleration, helps to minimize axle wrap.  Mopars don't need traction bars.   You get a short segment up front to locate the axle, and the long segment is the actual spring part.  Gives better handling without having to add stuff to the rear suspension.  That is how it was explained to me by a life long Mopar mechanic, and Votech instructor.
« Last Edit: January 14, 2008, 11:48:23 by Bill55az »
Logged
1980 Diplomat coupe, slant 6

patrickgrossman

  • Dippy God
  • ****
  • Offline
  • Posts: 1412
Re: Mopar leaf springs info
« Reply #6 on: January 14, 2008, 11:51:07 »

As far as I know, Mopar is the only car maker using short front, long rear segment dimensions.

Thats correct, anyone know why they did that? A very good reason only a gearhead would love.

the short front segment is much stiffer than the rear segment, so the majority of the deflection happens in the rear, and it
limits spring wrap.  it's acting very similarly to a ladder bar suspension, and why moparts use pinion snubbers instead of
slapper bars to control axle housing rotation.
Logged

unclemike

  • Dippy God
  • ****
  • Offline
  • Lancaster County PA
  • Posts: 768
Re: Mopar leaf springs info
« Reply #7 on: January 15, 2008, 10:05:25 »

Watch a Mopar take off, it looks like there's a jack under the body. Anyway, Mopars always suffered from soft spring rates. Unlike the Fords and GM products Mopar couldn't isolate road vibrations with rubber frame to body mounts. Hence in later years the rubber mounted front K member and the iso-clamp rear suspension.
« Last Edit: January 15, 2008, 10:09:17 by unclemike »
Logged

Reggie

  • Gran Fifthlomat Meister
  • Global Moderator
  • Dippy Oracle
  • *
  • Offline
  • Maryland - DMV Area
  • Posts: 5051
Re: Mopar leaf springs info
« Reply #8 on: January 15, 2008, 22:42:05 »

I do know that the F/J/M front spring segment lengths are the longest of any Chrysler car built through 1989. - RR

BZZT - Wrong  :oops:  :p   I just looked at the Chassis Manual and I forgot about C-bodies which aren't on the chart.  It says that they were even longer at 25" and 27".  Yikes!! - RR
Logged
"There is only one success - to be able to spend your life in your own way." - Christopher Morley 1890-1957, American author and editor

Library format and content © 2007- 2012 Reginald A. Royster, Sr., unless otherwise authored or noted.

S-type

  • Dippy Oracle
  • *****
  • Offline
  • Posts: 3586
Re: Mopar leaf springs info
« Reply #9 on: January 16, 2008, 07:31:21 »

I do know that the F/J/M front spring segment lengths are the longest of any Chrysler car built through 1989. - RR

BZZT - Wrong  :oops:  :p   I just looked at the Chassis Manual and I forgot about C-bodies which aren't on the chart.  It says that they were even longer at 25" and 27".  Yikes!! - RR

Thats what makes the C leaves great for building up Dip spings to 6 leaf setup! Works like an S/S spring but doesn't ride like it.
Logged

Reggie

  • Gran Fifthlomat Meister
  • Global Moderator
  • Dippy Oracle
  • *
  • Offline
  • Maryland - DMV Area
  • Posts: 5051
Re: Mopar leaf springs info
« Reply #10 on: January 16, 2008, 13:27:33 »

I do know that the F/J/M front spring segment lengths are the longest of any Chrysler car built through 1989. - RR

BZZT - Wrong  :oops:  :p   I just looked at the Chassis Manual and I forgot about C-bodies which aren't on the chart.  It says that they were even longer at 25" and 27".  Yikes!! - RR

Thats what makes the C leaves great for building up Dip spings to 6 leaf setup! Works like an S/S spring but doesn't ride like it.

Which leaves did you use where S-type?  I'm guessing the second leaf since the main won't work?? - RR
Logged
"There is only one success - to be able to spend your life in your own way." - Christopher Morley 1890-1957, American author and editor

Library format and content © 2007- 2012 Reginald A. Royster, Sr., unless otherwise authored or noted.

S-type

  • Dippy Oracle
  • *****
  • Offline
  • Posts: 3586
Re: Mopar leaf springs info
« Reply #11 on: January 16, 2008, 18:05:34 »

Which leaves did you use where S-type?  I'm guessing the second leaf since the main won't work?? - RR

Now your really taxing an old mans memory. Your right, the main was from the Dip and I had to drill the hole out to the '68 style spring pin as I used '68 plates etc. I think it was the third C body leaf I started with maybe, as the second was longer than the dip on the front segment. Anyway, what you end up with is the first leaf under the main actually ends right at the front of the main leaf. This backs up the main 100%. Then they taper back about 4" every leaf from there for a total of 6 leaves. This creates an ultra stiff front segment that will not wrap-up. The car will raise in the rear on launch a few inches and the car literally pushes the axle down with the snubber. It doesn't spin more than 10' or so at the most and this thing has huge low end torque. Because of the long tapers in the rear segments, it still rides reasonably well compared to the S/S springs. Those things will knock your fillings out.

By the way, Mopar springs are side specific. Left and right springs are not the same on most models. The right spring usually has a little more to it and sometimes an extra leaf. So if you play with Mopar springs, know which side they are for and don't mix and match the pieces.
Logged
Pages: [1] |   Go Up