4 Or 5 Ply Leaf Springs?

[Caper50]

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]

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+2GT]

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]

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]

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]

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]

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+2GT]

I have GT 4-leaf, Kayaba Gas-A-Just, and Traction Master bars. Smooth ride, excellent cornering, no wheel hop.

 

[horse sence]

perfect set up. a stiffer suspension is not allways the way to go

 

[robbz28]

I have the 4.5 mid-eye grab a traks and love them. The factory springs had done got all soft on me

 

[bikefreak600]

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

my car was cracked here as well. and it had air shocks when i got it.

 

[horseballz]

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]

I think I paid $249 for mine like 5 years ago....I did have alot more disposable money back then though.

 

[horse sence]

my car was cracked here as well. and it had air shocks when i got it.

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]

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).