Mustang Owners Club Australia Forum

Technical & General Discussion Area => Tech Torque Pre 1973 => Topic started by: Gastill on June 05, 2016, 10:26:03 pm

Title: Rear Leaf springs
Post by: Gastill on June 05, 2016, 10:26:03 pm
Hey Gents

I'm looking for a bit of advise on leaf springs, hope you can help.

So I have a 66 fastback K Code, certain that rear leaf springs are original. Every piece of evidence said they had never been apart from the axle. The springs are four leaf, and sorry but I did not yet clean them to check the part number.

I brought a set of springs from here in the used section. When I put the two sets side by side the hole centres are the same. if i draw a straight line between the eyelets of the springs and measure distance to the top of the upper leaf they are also both the same.

However one set is 4 leaf and the other is 6 leaf. From the info  on line there appears to be a lot of 4 leaf sets.

Can anyone advise if there was a factory option for heavy duty leaf spring package available on the 66 Mustangs. Or would a 6 leaf set be some aftermarket thing.

Cheers
Greg

Title: Re: Rear Leaf springs
Post by: unilec5544 on June 05, 2016, 11:12:22 pm
You should just get your original 4 leaf springs reset, if they are in fact original.
Title: Re: Rear Leaf springs
Post by: trav68 on June 06, 2016, 11:41:01 am
Greg - 6 leaf springs would be incredibly stiff. You know there are a couple old school springs works left in Perth  (Westralia Spring Works) who can probably work work your old ones to keep the authenticity.
Title: Re: Rear Leaf springs
Post by: barnett468 on June 06, 2016, 01:24:34 pm
6 leaf should be massively stiff.

if you do any type of performance driving and like a firm buy not harsh ride, you need to buy stiffer springs . i use 125's and 135's.

lots of guys here use Kings Springs.
Title: Re: Rear Leaf springs
Post by: Shep69 on June 07, 2016, 03:04:59 am
Greg, I used Fremantle Spring works to reset the ones on my 69 . They turned out fine.
Title: Re: Rear Leaf springs
Post by: Gastill on June 07, 2016, 10:58:00 pm
Guys I really appreciate all your advice, and will be having the 4 leaf pair reset.

Thanks heaps

Now to find anew ho,e for those 6 leaf

Cheers
Greg
Title: Re: Rear Leaf springs
Post by: trav68 on June 08, 2016, 01:18:39 am
Confirm whether they are cold or hot ( ie heat treating) resetting them too.
Title: Re: Rear Leaf springs
Post by: Gastill on June 14, 2016, 02:38:35 pm
Thanks Trav, good advise.

As a novice to this which is the better process

Greg
Title: Re: Rear Leaf springs
Post by: barnett468 on June 14, 2016, 06:05:24 pm
Thanks Trav, good advise.

As a novice to this which is the better process

Greg

never heat a spring it will loose its springyness.
Title: Re: Rear Leaf springs
Post by: trav68 on June 17, 2016, 12:56:48 am
Greg, "hot reset" by a spring works with a temperature controlled furnace, including quenching and tempering processes will ensure correct mechanical properties are achieved. Q and T processes require certain temp ranges and cooling rates via oil and air respectively to ensure microstructure ( = mech properties ) of steel.
Title: Re: Rear Leaf springs
Post by: barnett468 on June 17, 2016, 10:45:14 am
Greg, "hot reset" by a spring works with a temperature controlled furnace, including quenching and tempering processes will ensure correct mechanical properties are achieved. Q and T processes require certain temp ranges and cooling rates via oil and air respectively to ensure microstructure ( = mech properties ) of steel.

That is a completely different deal altogether.
Title: Re: Rear Leaf springs
Post by: Gastill on July 06, 2016, 10:23:28 pm
Gents

Great advise, and many thanks.

Now off to find the right place to get it done

Regards Greg
Title: Re: Rear Leaf springs
Post by: Glen Mach 1 on June 20, 2021, 08:44:07 pm
Hi all,

I saw this old post and wanted to ask a similar question about the rear leaf springs on my 1969 Mach 1.  It has bottomed out a few times and the back springs look pretty pitted and original.  I see the previous advice is to have them resprung but also wanted to see if anyone had replaced theirs and what they went with and results.

Thanks

Glen
Title: Re: Rear Leaf springs
Post by: AussiePhil on June 21, 2021, 06:22:50 pm
Hey Glen,
Saying that it bottomed out, is the car sagging in the back!
Resetting them will lift the road height, is that what you want or do you want same road height but stiffer.
Are your shocks in good condition.
Resetting (hot or cold) will only raise or lower as required and will not make stiffer.
You may need to add a stiffer lower leaf.
A real good modification is to add a half leaf over the main spring running to the front of the car to stop axle tramp.
You can YouTube resetting car leaf springs, this may explain!
Cheers Phil.
Title: Re: Rear Leaf springs
Post by: AussiePhil on June 21, 2021, 08:06:23 pm
Hey Glen,
I've got a lovely set of leaf springs off my 68 coupe, I fitted four links and Coil-over shocks.
They are five leaf with a half leaf on top for axle tramp.
Photo attached to give you an idea!
Cheers Phil.
Title: Re: Rear Leaf springs
Post by: nickd on June 22, 2021, 12:24:47 pm
For our 65 I bought a new set of mid eye springs from a local Mustang supplier. They retained most of the original comfort and also lowered the back by about 1.5 inches.
Title: Re: Rear Leaf springs
Post by: AussiePhil on June 29, 2021, 08:50:18 pm
Hey Glen,
Having roblems with new email! Email me at phildrury59@gmail.com
I've fitted Helix four link coilover suspension so no longer required!
68 mustang heavy duty leaf springs, 6 leaf, one leaf over the eye springs, new rubber bushes, set up for axle wrap, reset May 2016 at a cost of $200.00, can show you invoice, hardly used since, 51" overall, 31" and 22 1/2" across the arc to the eyes ($200.00).
Not sure how much to get the to Brisbane if you are interested,!
Cheers Phil.
Title: Re: Rear Leaf springs
Post by: Glen Mach 1 on July 06, 2021, 02:46:59 pm
Thanks Phil - I'll get under mine and take a look on the weekend.