Topic: Length of shackles

[rocnhrse]

1967 gta s code April San Jose  3:00 gear I just took the shackles  off my rear leaf springs  and the new replacement  ones look to be approximately  1 in longer the package  said they were for a dual  exhaust  car  ,what would be  the proper  length
Thx john

[J_Speegle]

Have never heard or seen a different length of shackles being used on cars based on the type of exhaust. On early cars there was a different design used for one side to clear the exhaust though

[Bob Gaines]

Have never heard or seen a different length of shackles being used on cars based on the type of exhaust. On early cars there was a different design used for one side to clear the exhaust though

I was looking through the newest NPD catalog for any new added items and noticed a extra long shackle that they offered to offset the effects of sagging leaf springs or to adjust the standard lower in the rear Mustang stance.This is the first time I have ever heard of a longer shackle. Maybe the one that is the subject of this thread may be a after market something like the NPD is offering. Just a thought.

[rocnhrse]

I will  use the longer ones for now  because  theses cars sat low at the back if I don't  like it it's a easy change, I am using my  original  springs

[WT8095]

Keep in mind that longer shackles are going to allow the leaf spring to flatten out under load slightly more than it was designed to. This is going to accelerate the fatiguing/creep/relaxation of the leaf springs, which is already far enough along that the car is sitting low. Eventually you'll end up having to replace the springs or restore them.

[Bob Gaines]

The ones npd sells look like a factory piece (even though they are not).  I can remember back in the late 60's -70's that it was common to add "shackles",as it was referred to.  They were after market generic longer steel plates usually chrome plated with mounting holes positioned evenly along the length so as to provided the adjustable height change of choice. It was done for tire clearance (big tires in back) and or to give the more streamlined look of higher in the back. Also done because when these cars were every day tranportation it was not uncommon to bottom out over small bumps when carrying two people in the back . Raising the back eliminated that bottoming out. I car pooled with my 69 back in 70-72 is how i know first hand.   

[rocnhrse]

Thanks for the advice  I will go with original  height

[rocnhrse]

Sorry  here is a better pic