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4 Or 5 Ply Leaf Springs?

  • Thread starter Thread starter Caper50
  • Start date Start date Jun 19, 2012
C

Caper50

New Member
May 10, 2012
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Jun 19, 2012
#1
  • Jun 19, 2012
  • #1
Just wondering what the best option is for my 66 289 coupe. I've seen 4 and 5 ply versions for sale on line. What are advantages or disadvantages of each. Thanks
 

rbohm

Founding Member
Apr 12, 2002
6,698
550
204
tucson,az
Jun 19, 2012
#2
  • Jun 19, 2012
  • #2
four leaf springs are generally softer for a better ride, where as five leaf springs are stiffer for better handling. the five leaf springs also dont wrap as hard as the four leaf springs do. another choice would be the flex-i-form fiberglass leaf springs. they are a single leaf spring, dont wrap like the steel springs do, are much lighter than the steel springs, though they do cost more. the ride and handling of the fiberglass springs is comparable to the steel springs.
 
2

2+2GT

10 Year Member
Apr 25, 2009
3,333
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79
Southeastern Pennsylvania
Jun 20, 2012
#3
  • Jun 20, 2012
  • #3
Even the mighty BOSS 429 NASCAR-engine Mustang had 4-leaf springs. 5-leaf would tend to be stiffer than that. Putting ultra-stiff springs on your car to solve a handling problem is fine for a competition car, but if you are driving on the street there are more sophisticated ways. Upgraded shocks, sway bars, and Traction Master or Grab-A-Track arms are just a few. Putting in semi-rigid rear springs, similar to a Chevy pickup truck, would not be my first choice to solve a handling problem.
 

65fastbackresto

Active Member
Apr 13, 2007
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Jun 20, 2012
#4
  • Jun 20, 2012
  • #4
I went 4 1/2 leafs and I couldn`t be happier. Good firm ride and no axle wrap when I burn the tires.
 

horse sence

15 Year Member
Nov 29, 1999
12,239
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Wile Coyote's stunt double
Jun 20, 2012
#5
  • Jun 20, 2012
  • #5
4 leafs are fine unless you have passengers in the rear seat then you may find your tail draging ,one thing i would not recamend is air shocks or heavy duty coilover shocks they are to much for the rear crossmenber and cause it to crack across the shock access holes from the floor flexing if the shocks wont give something else has to
i have worked on several cars that had air shocks at one time and the floors are always cracked there
 

Rusty67

20+ Year Stangneter
Dec 3, 2002
3,749
37
109
LA, CA
Jun 21, 2012
#6
  • Jun 21, 2012
  • #6
I have 5 leafs on my 67 and I hate them. They handle GREAT but they feel like trash on speed bumps and pot holes. They are even fairly bad over the speed humps. I would go more then the 4.5 leafs. The fiber glass ones are also a great option. I think I will be going with those at some point.
 

PoppyMod

Member
Jun 27, 2010
617
6
19
Severna Park, MD
Jun 23, 2012
#7
  • Jun 23, 2012
  • #7
Hi,
If your ride is a street cruiser and simply want a little better suspension with better handling and road feel, go with 4 leaves. As mentioned, the 5s are for more spirited handling and track work. If you insist on burn-outs, add Caltracs. Keeps the axle in check with out sacrificing your "buttocal" happiness!
 
2

2+2GT

10 Year Member
Apr 25, 2009
3,333
10
79
Southeastern Pennsylvania
Jun 23, 2012
#8
  • Jun 23, 2012
  • #8
I have GT 4-leaf, Kayaba Gas-A-Just, and Traction Master bars. Smooth ride, excellent cornering, no wheel hop.
 

horse sence

15 Year Member
Nov 29, 1999
12,239
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Wile Coyote's stunt double
Jun 23, 2012
#9
  • Jun 23, 2012
  • #9
perfect set up. a stiffer suspension is not allways the way to go
 

robbz28

10 Year Member
Sep 23, 2009
775
5
39
Epps, LA
Jun 23, 2012
#10
  • Jun 23, 2012
  • #10
I have the 4.5 mid-eye grab a traks and love them. The factory springs had done got all soft on me
 

bikefreak600

Member
Dec 10, 2005
156
2
19
rochelle IL
Jun 24, 2012
#11
  • Jun 24, 2012
  • #11
horse sence said:
4 leafs are fine unless you have passengers in the rear seat then you may find your tail draging ,one thing i would not recamend is air shocks or heavy duty coilover shocks they are to much for the rear crossmenber and cause it to crack across the shock access holes from the floor flexing if the shocks wont give something else has to
i have worked on several cars that had air shocks at one time and the floors are always cracked there
Click to expand...
my car was cracked here as well. and it had air shocks when i got it.
 

horseballz

10 Year Member
Sep 30, 2009
824
19
49
Las Vegas, NV
Jun 24, 2012
#12
  • Jun 24, 2012
  • #12
I have 4 1/2 leaf standard eye units from Maier Racing and love 'em. Stock height, a tiny bit stiffer ride than stock and no wheel hop! Of course I got the ultimate deal/price on them. A member here posted them brand new never installed for $50, but was located near Lancaster, CA and I'm in Las Vegas, NV. My son just happened, on that day, to be returning from a visit to Modesto, CA and driving past, within 3 miles of the guys home. YEE-HAA! FREE SHIPPING!
Gene
 

65fastbackresto

Active Member
Apr 13, 2007
1,229
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39
AR
Jun 26, 2012
#13
  • Jun 26, 2012
  • #13
I think I paid $249 for mine like 5 years ago....I did have alot more disposable money back then though.
 

horse sence

15 Year Member
Nov 29, 1999
12,239
8,092
233
Wile Coyote's stunt double
Jun 26, 2012
#14
  • Jun 26, 2012
  • #14
bikefreak600 said:
my car was cracked here as well. and it had air shocks when i got it.
Click to expand...
yea when you air those shocks up you take the weight off the leafs and place it on the rear cross member and shocks. i have seen the shocks punch through the brace , this was a pretty common thing to do in the good old days ,me included,the coil overs were just as bad . i still see people do this, bad idea.set the springs up right in the first place its a lot cheaper in the long run, the 4 leaf with a half leaf in the front is probably the beter way to go not as stiff and the front leaf helps stop wrap up and if you still get wheel hop add traction bars
 

SoCalCruising

Founding Member
Jul 25, 2000
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47
SoCal
Jun 27, 2012
#15
  • Jun 27, 2012
  • #15
The big mistake some make is to combine a 5-leaf with stiff shocks. That makes for a horrible ride. Anyone not satisfied with 5-leaf springs and wants an easy improvement, add a soft shock. I have Cure Rides and they're fine. Not saying the ride isn't stiff, but I can live with it.

4 or 41/2 leaf springs with CalTracs (if needed) is nice. Add a sway bar for even better handling. Del-alum bushings also help (Global West product).
 
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