Need Opinions On Shackles!

[prayers1 153]

I'm needing to replace the original Shackles. The vehicle will basically be used for normal driving and cruises, some street racing every now and then, 300 hp 289, 4 speed toploader and a 3:50 posi.

 

I still have the stock suspension and may upgrade the leafsprings in the future. I have 295/50R15 tires, 15 x 10 rims w/ 5.5 bs and air shocks.

Of course, without airshocks, the tires will rub if the vehicle is loaded or going around turns.

 

I see so many options for Shackles/Bushings.

Grease Fittings

Polyurethane or Rubber Bushings

Dual Exhaust Design

1" Extended Shacklle.

 

I was wondering if I would need air shocks if using the 1" extention.

I really don't like that high lift shackle look that I've seen on other cars, so is the longer Shackle noticable or does it retain the stock appearance.

 

I like keeping the tires even with the outside of the fender, I don't like the tires sitting in looking stuffed.

 

What would be my best option?

 

Thanks to All!

[Powershift 19]

Your BEST option... replace the worn out springs, get new stock length shackles, and a good set of shocks.

 

Don't use extended shackles, or air shocks. Those are simply bandaids for worn out parts.

[prayers1 153]

Powershift-Yes, I agree that would be my best option.

 

What about Polyurethane vs. Rubber bushings. Would the poly's be stiffer on body roll.

 

Also, how to keep the 1/4 panel off the tire. I see that your tire fits inside the wheel well. I want mine to fit inline with the outside of the 1/4 panel and in doing so they will rub if I go stock requirements.

 

Would a stiffer spring work?

[maxum96 32]

Stay away from extended shackles and airshocks as powershift said. You have too wide of a rim and tire on the back. I would also be willing to bet you have a wheel with the incorrect offset. That's why that stick out past your wheel well. I run a 275/60/15 tire with the factory offset in the rear and I can barely get it to fit inside my wheel well. With your power level you'll be fine with stock bushings and shackles on your car. I currently run stock shackles and bushing in my leaf springs. But I do have Global West Del-A-Lum bushing to go in my springs when I get around to it.

Edited August 4, 2012 by maxum96

[69gmachine 15]

Powershift-

What about Polyurethane vs. Rubber bushings. Would the poly's be stiffer on body roll.

 

IMO there is absolutely nothing to be gained by going to a poly bushing except a harsher ride. Maier Racing has some springs that are biased to the front to resist wrap up, but it's a 300 year old design that belongs in the history books, not in a performance car IMO. However, I'm stuck with them too for now. I had a long conversation with Mike Maier (who races Autox and has won several championships) and his current philosophy is to use the softest bushings out there and a panhard rod for a leaf sprung car.

 

Also, how to keep the 1/4 panel off the tire. I see that your tire fits inside the wheel well. I want mine to fit inline with the outside of the 1/4 panel and in doing so they will rub if I go stock requirements.

The quarter panel attaches to the outer wheel house with a lip that faces the tire. If you line up the outside of the tire with the outside of the 1/4 panel you're asking for trouble. The tires will get cut if/when the suspension compresses. The correct offset wheel and rolling the outer lip is the best answer here.

 

Would a stiffer spring work?

Yes it will work, but probably not any better. As Powershift mentioned, if the springs are just old and sagging, then new springs are in order. I believe in using the softest springs that are stiff enough to get the job done. A softer spring will track the ground better, plus it's easier on your backside.

[rwcstang 201]

Your BEST option... replace the worn out springs, get new stock length shackles, and a good set of shocks.

 

Don't use extended shackles, or air shocks. Those are simply bandaids for worn out parts.

 

I agree, I had air shocks before and it wasn't a comfy ride at all. I was just bouncing every where lol so I bought my self some Global west Shackles, along with 5 reverse eye and some KYB shocks. my car should perform well once its on the road again.

[prayers1 153]

When you say stock bushings are you meaning rubber.

 

I had 275's before on 8" rims and I still wanted a wider look.

 

The reason I bought the current 69 was because I'm stuck reminiscing my 1st 1969 Mach 1 (mid-age crisis). I wanted to duplicate that look. I like the wide 15" look on the 1st car. It had a Mickey Thompson N50's. I don't care for the stuffed wide tire and low suspension, it reminds me of the Hotwheel Cars

 

I wonder If I should go to a 9" rim. I currently have Weld ProStar .

 

Regarding leafsprings. Is there a certain spring rate I should look for or are they all the same. I plan in the distance future to get a 351 Cleveland.

 

Here's a picture of that 1st car. You can see the wide rear tire. I'm thinking that it might of been a 14" rim.

 

Thanks to all!!!!

 

[prayers1 153]

Thank you for your comments. I was unable to read the past 2 before my reply, since I was in the processing posting.

 

What is reverse spring and how will that affect me and would that be something I should consider. In regards to softer spring, will make the car to sit too low or would it still be at the factory height with just a softer ride.

For what I'm shootting for, what would be the spring rate I would need.

[maxum96 32]

I had 275's before on 8" rims and I still wanted a wider look.

 

 

My rims are 8" wide in the back with 275/60/15 tires with about a 2 1/2" drop in the rear.

[Klutch 17]

IMO, longer shackles are like mullets. Lots of guys do it, but it doesn't make it a good idea.

 

Very good advice above. Adding longer shackles would be treating the symptom and not the problem. The problem is indeed that you have the wrong wheels and tires on your pony.

 

Dollars to doughnuts, you'll be able to easily sell the wheels and tires you're running now. (Probably to a guy a with a mullet.) Apply the money you get from the sale and a little bit more green and get a set of properly spaced wheels with tires that fit inside the quarters.

[prayers1 153]

OK, the consensus is to keep the stock suspension with rubber bushings and 275's.

 

Will any leafspring do?

What do I need to know when ordering leaf springs.

What leafsprings do you guys recommend.

 

If I roll the lip, is 275 the widest I could go w/out air shocks?

 

Thank you again to all!

[shelbyshelby 52]

Prayers1,

I feel like some are trying to change how you want your ride. It's done in good taste though, unlike other forums I keep up with. End rant. I wouldn't use the longer shackles either for height. Back in the day, I used them and a buddy of mine told me on a few occasions he could see the rear end shift from side to side. I'm building a 69 mach1 now, I installed the global west bushings that maxum spoke of. They seem like they will control the lateral movement of the rear end, which is a contributing factor in the tires rubbing in lowered cars especially. I also used the 428 springs to help in the stiffness and hopefully maintain ride height under load better. My car isn't assembled yet, but thought I would mention it, to help iron out which parts to buy. The global west bushings work like a bearing almost, I will buy them for my 68 coupe when I upgrade the rear end on it. I would recommend changing the springs and bushings first and drive it bit and see if you need further parts. One thing I remember a local done long ago for increased ride height was he cut his spring perches off and welded them to the top of the rear end. This made the rear bolt to the bottom of the leaf springs and looked like it added 6 inches of height to the car. I didn't like it, it was way too high, but that was cool around my neck of woods. I have repaired cracked shock mounts from using air shocks, I guess it puts a lot of stress where it wasn't designed to. I think the upper shock mount is a weak design even for the factory shocks, just looks like the metal would flex before the shocks move. I hope you keep to the look your after, it takes me back to the good ole days too. Seems to be plenty of lowered cars around to look at, nice to see different looks.

[prayers1 153]

shelbyshelby-

What I like about this site is that there isn't a certain trend that is followed. There is a mix of all different styles and applications. I feel that whenever I ask a question, I get very good feedback with some great ideals. Of course I make the final decision

and I don't claim to be a know it all, it's a great site to get one's past & present experience.

 

My first car that I posted above, had a 428 CJ, C6 and a 4:30 rear and I still used airshocks. I guess back in the day (1980) wide tires and a jacked up rear was in. I kinda got stuck on that style.

 

As for which type of spring to buy, you purchased a 428 set. Is that because it's stiffer or does it raise the rear up.

[prayers1 153]

From scanning CJ Pony, I find that there are 3 types of springs 4, 4.5 and 5 leafs.

The 4.5 seem to be for more torque like 428's and the 5 seem to control wheel hop and are rated at 195 lbs.

 

Which do you think fits best in my application?

[Powershift 19]

From scanning CJ Pony, I find that there are 3 types of springs 4, 4.5 and 5 leafs.

The 4.5 seem to be for more torque like 428's and the 5 seem to control wheel hop and are rated at 195 lbs.

 

Which do you think fits best in my application?

 

 

Keep in mind many of the 4 and 5 leaf springs out there don't have very accurate weight ratings (if any at all). Don't put all your trust in spring weight with how many leafs are in the pack.

 

Maier Racing's leaf springs are designed more like a control arm, with more leafs being towards the front perch. This helps prevent axle wrap on hard acceleration. Their springs are also TRUE to the weight rating. A 200lb rear leaf spring from Maier really is a 200lb rated spring, and their 165lb springs are their actual rating too. As mentioned, the optimum setup with this type of spring is the addition of a Panhard Bar.

 

I've done a bunch of research in the build for my Mach. Short of doing a completely different (aftermarket) suspension geometry the leaf spring, with a Panhard bar, can REALLY be made to work well. Good shocks are a crucial part of the equation too.

 

I've already added Maier's 200 rear springs and Bilstein shocks, with a Panhard Bar to be installed next. I've felt a HUGE improvement with simply the new springs, stock style rear shackles with rubber bushings, Urethane front bushings, and the Bilsteins. I even ditched my Shelby Under Rider bars, per Mike Maeir's suggestion. He KNOWS what he is talking about, and it shows in my car's performance.

 

ANY tire and wheel combo which sticks out of the wheel well housing will run the risk of tire rub, unless you run something like air shocks. But, as mentioned, air shocks are going to provide a horrible ride. They are a 1960's fix to the crappy selection of wheel offsets and tires at that time. There is no real excuse for it in this day and age.

Edited August 5, 2012 by Powershift

[shelbyshelby 52]

I bought my springs from npd, Detroit eaton. I am hoping it has a stiffer spring rate to hold up rear better with a load (family of four).

[Klutch 17]

Prayers1, I feel like some are trying to change how you want your ride.

 

Well, he DID ask. :smile:

 

I wouldn't walk up to a Mustang owner out of the blue and say, "Dude, you need to get rid of those shackles!". But when somebody asks for input, I think it's OK to politely provide input.

[LoneWolf2U 136]

From scanning CJ Pony, I find that there are 3 types of springs 4, 4.5 and 5 leafs.

The 4.5 seem to be for more torque like 428's and the 5 seem to control wheel hop and are rated at 195 lbs.

 

Which do you think fits best in my application?

 

4 leaf stock ride height may settle some.

4.5 expect a 1/2 rise in ride height some what stiffer.

5 leaf 1/2in rise, rides like an unloaded truck.

[prayers1 153]

Powershift- Very good information, Thank You!

 

Right now I'm replacing both full 1/4's, tail panel, trunk drop offs and right frame rail. Since I need to pull the rear, I thought now would be the time to replace the shackles and springs. Right now Maier Racing products don't fit into my budget, even though their one of the best. I'm just gonna stick with mostly stock OEM parts.

 

From what I gathered, I'll go with stock rubber bushings and 4.5 leaf set. Hopefully the new springs will raise the car up enough to use a good set of shocks. I'll try to steer away from tires sticking past the inner fender and maybe roll the lip.

Any Pro's or Con's on rolling the lip?

 

I was thinking, if I go with a 9" rim the only part that would be wider with 275's would be the sidewall. Then I guess using a 8" rim would make the 275's taller (I know not by much). Is there any gain to a wider tire stance using a 9" rim. Wrong or Right?

 

So, who makes a good OEM rubber shackle set and 4.5 leafsprings.

 

Thank you to all who replied!

[69gmachine 15]

Eaton/Detroit is licensed by Ford to reproduce the OEM springs and they have multiple rates that are as accurate as they were when the car was new. They also have good rubber bushings. Go here to pick out your springs:

http://www.eatonsprings.com/64-73mustangrear.html

 

If you want stiff and tall, get the ones for a 428 vert. For medium, go with a set for a Windsor fastback. The softest would be for a 6 cyl coupe. Pick out the ones you want, find a dealer and order the ones you want even if it's not listed in the catalog.

[prayers1 153]

68gmachine- Thanks so much for that information, It has a lot of options and details each item, plus the pricing isn't bad.

 

I now have a plan of what I'm gonna do. I want to Thank All for your help and input!!!!!!!!!!!

[DRASTiK 22]

Little more info about leafs, just in case.

 

http://www.opentrackerracingproducts.com/leafsprings/