55 T-bird suspension improvements?

G

Grumpy Rick

Senior Member
Now that I am getting well along at making this Bird run well, I am starting to think ahead, to when I can get to a few other items that need attention.

When I got this '55 T-Bird, I looked it over very carefully, and noticed that it had two different leaf springs in the rear. I triple checked for obvious frame damage and found none, so I went ahead and bought it because all the hard stuff like body, paint and rebuilt motor were done. And, I got a pretty good price on it.

It tracks just fine, but the springs are definitely not a matched pair. Since I will eventually replace them anyway, I am wondering about getting some slightly stronger units. My '55 shop manual shows the rear springs to be AH-5560-D. They are rated at 665-685# capacity, 5 leaf, 2" wide, 48" long..

I wonder if anyone has a '56 manual and could see what number those springs are? Am I right in assuming they would be a bit stiffer, to compensate for the '56 continental spare tire setup?

Does anyone have a recommendation for better front and rear springs, shocks, and sway bars? Not trying to make a race car, just want it to handle better, and not be a tail dragger.

The guy I got this from did a very nice job on most of it, but a few areas are real head scratchers. Some strange stuff here and there, like the carb/distributor mismatch, and the 14" wheels.

Thanks
 
Rick,
The '55 T-Bird leaf springs are one yr only (48 inches long) the '56/'57 are a few inches longer.
Not sure if springs from another Ford model will fit. The front/center/rear dimensions are listed in the ebay link below.
FYI, (from a CTCI judging document) the OEM rear ride height for a '55 Bird is 26.5 inches, plus or minus 1 inch, from the center of the tail light to the ground. Front is 28.5, center of headlight to ground, plus/minus 1 inch.
I'm assuming that's with the stock 6.70x15 bias ply tires. If you have 205/75R15 tires the car would be approx 1/4 inch lower.
https://www.dbtires.com/crossreference.html

Most T-Bird Resto places sell 'original' replacement leaf springs but the prices are higher.
Some of them may have good used ones available too.
If there is a good spring & suspension shop near you they can likely rebuild and add a leaf to the pair you have for less than​ the price of new replacements. (longer U-bolts may be needed)
My rear leaf springs are mismatched as well so I bought a replacement set, just in case.
Dayton part # 42-199, made in the US.
A parts or repair shop near you may be able to get them for a good price.
http://www.ebay.com/itm/REAR-LEAF-SPRINGS-FORD-THUNDERBIRD-1955-/282378017833?_trksid=p2047675.l2557&ssPageName=STRK%3AMEBIDX%3AIT&nma=true&si=8TbrjgBwaH652jxB3%252FezeUYt9x4%253D&orig_cvip=true&rt=nc

There are HD front & rear sway bar kits available, it may take a little looking to find them at a price you like. (example)
https://www.summitracing.com/search...9&SortBy=BestKeywordMatch&SortOrder=Ascending

Front coil springs...
The Aerostar van had coil springs with a progressive winding that make for a smoother and slightly lower(?) ride. I've not looked into them as an option but apparently they are 'the thing to have'.
Double check all the upper and lower control arm bushings. The rubber dries out and they have to be replaced. (photo below)

Shocks...
I like gas charged shocks. They are available over the counter at most auto parts stores. Pick a store and name brand you like. (example)
http://www.oreillyauto.com/site/c/s...ear=1955&make=Ford&page=1&results=20&sortBy=2

As you get the car running and handling better you may want to consider front disc brakes.
http://www.dropnstop.com/bolt---on-kits.html

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FWIW, I've got the Aerostar springs on the front of my bird. C/L of the headlight is 26" with 225/60 15 tires. The rear at the taillight is 22". I do not have a problem bottoming out or over speed bumps.

All the major Thunderbird suppliers list a sway bar kit as well as gas shocks. I think you can save a few bucks just buying the shocks as mentioned above. Addco still lists a 55-57 bird front and rear bar, both at 7/8". That sounds a bit stiff in the rear to me for a 55, probably better on a 56 or 57 depending on the spring rates.

http://www.addco.net/aftermarket/

Edit
Should have checked the link first. Summit lists the Addco bar I listed above
 
miker98038 said:
FWIW, I've got the Aerostar springs on the front of my bird.....
Click to expand...
I'm assuming it's the front coil springs from the Aerostar? (IIRC the rear coils were taller)
Do you have a part number? or any helpful hints?
There might(?) have been a couple front spring options for the Areostar, I had one with the all-wheel-drive option and it seemed a bit taller than the rwd version.

.
 
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I've been driving my 55 bird since 1967.
I have tried several renditions of springs packs for the rear and none that I can recommend. I will say that I would not go stiffer with a spring pack. I have done all my (good) suspension upgrades with Bilstein gas shocks, sway bars and aerostar coil springs in the front. My car handles extremely well on corners and tracks straight as an arrow. BUT it does and has always ridden pretty darn ruff in the back end. It's not easy to fix or cheap for me to experiment around with other options but I have been wondering lately about removing one rear leaf. I also have heard some mixed reviews on the use of mono leaf springs as an option. Again I'm not willing to spend the dough to experiment. But just to reiterate, I would not go stiffer on the springs. 56 and 57 have longer springs and generally ride smoother.
So maybe that it the real answer. Check into changing the spring mount position and get longer springs. Again not a cheap fix and really just a thought.
In my younger days I was a lot tougher and put up with the ride because of the trade off of it not being slushy riding, but now I would really like to soften it but of course keep the sway bar control and anti-roll.
I'd welcome more comments on this subject. my car is by no means stock and isn't ever going to be.
 
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Here's a link to the Aerostar springs on yblocksforever. There's a bunch of them on the HAMB too. Some think their too low with Granada spindles, others use both with or without a spring spacer. I like the fact they're a progressive winding. Smooth on the small bumps but don't bottom on the big ones. Front springs, rear drive only, 1987 or so.

Moog makes them they're about a $70 deal at Amazon or elsewhere.

http://forums.y-blocksforever.com/Topic117546.aspx
 
Sure appreciate the info guys. I just measured my car, and the rear height is about 26 1/2", while the front is about 28". This is with those 14" wheels previously mentioned (2.15 X 70/14 tures),

The rear springs look slightly different, but I haven't measured them yet. The rear shackles are reversed, and the drivers side has a one inch lowering block (previous owner). I see no damage or repairs to the frame.

Now that I have it running well, I find that the car wallows around corners, and I hate that. My '56 Vickie handles much better, even though it is nothing to brag about, it is a floater too. I wonder why my previous '55 Tudor with the Chevy motor handled just great. Lighter motor, I guess.

I plan to take it to a suspension shop and have the rear springs rebuilt, and arched to set the rear at the proper height. I will go with y's guy's recommendation to not increase the stiffness, the arching should do the job.

Once that is done, I will try out a stiffer front roll bar, and maybe those Aerostar springs.

Y'sguy.......did the Aerostar springs lower the front of the T-bird? If so, how much?

Thanks, Rick
 
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Front height... I guessing the slightly larger tires & and the 14" wheel size are cancelling each other out to give you a 'normal' height.

Rear springs... Are the rear eyelets of the leaf springs above or below the bushed end of the 'J' shaped bracket on the frame? The ends of the springs should be above the bushed end of the frame bracket.
With reversed shackles and a 1 inch block on one side but not on the other, and the rear sitting level at a normal height(???) yes it's way past time to get those springs fixed.

Aerostar front springs... Summit is selling a pair of them for a pretty good price.
https://www.summitracing.com/parts/mog-cc850

If the spring shop gives you really bad news about the existing leaf springs you might keep the Dayton part number handy. (# 42-199)
http://www.ebay.com/itm/REAR-LEAF-S...ash=item41c4126eb6:g:vVIAAOSwWxNYqwsZ&vxp=mtr
.
 
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Grumpy Rick, yes the aerostar springs did lower the front but I can't recall how much. It was not greatly significant. I have pic somewhere. I may be able to find them. The wallowing is quite often bad worn out shackle bushings. But rebuilding the spring pack, you should be able to take care of that part. fyi, I ordered my springs direct from amazon. Just made sure the part nos. were correct.
 
Sorry, can't get my photos to load at this time.
However, the fender lip on the drivers side wheel measured 26 1/4" to the floor after freshly installed springs. I measured tonite and the distance is now 24 1/2". so they have settled in after several years of use.
Your measurements will vary as I have 17" wheels and low profile tires.
The actual measurement (spindle center to floor) is available in a factory spec drawing that I have somewhere? this will give you what it was supposed to be originally and you can go from there for comparison.
Also, the unloaded spring heights are different. The Aerostar is much (2-3"?) shorter, but this is not what makes for the drop, so don't let that confuse you.
 
For a full size car (Fairlane), the Aerostar springs, Moog #CC 850 will lower the front end about 3 inches. Surely less on a T-Bird. If this is too much, there are #CC 851 springs that are taller.
 
Dmsfrr,

Yup, that's how they hang. The shackles are flipped, with the spring eye below the hanger. Those Dayton springs on e-bay look pretty good to me. New shackles don't cost too much either.

I now have them on my list, when funds allow. I put KYB gas shocks on my 56 Vickie, and will probably spring (get it?) for them ASAP, as well as the sway bar.

I just want the car to be capable, and enjoyable. Just a nice cruiser, but not a cruise boat.
 
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