New Spring advice front and rear, Height of fenders, Passenger side rear is lower by 5/8" now....or maybe a bit lower.

[griffbl]

Both sides of car appears a bit low to my eye. Not a lot, as these cars are very low slung, but some. Measurements are without a spare tire in back (by phone is my flat fixer, and I drive this car close to home only for now). I don't want to raise her much, as i hate open wheel well, and i went as tall as i easily could with 14's without being too wide for my eye, this car's intended use, etc.

Driver's side rear is 26 3/4" and Passenger more like 26 1/8" on brand new 225/70-14's. Properly inflated....depending on surface, there can be nearly an inch difference. The differential in height is less important, than restoring ride quality, but hopefully I can get it a bit more level when through. Car seems a bit low in back, and my hunch is springs are really pancaked. Ride quality tells me as much. Has air shocks are in place, which are going away ASAP at the same time, as they don't usually help in the ride quality either and really in many cases depending on pre-load work against the spring's design. (I know people sometimes use them to level the rear of their cars, just not for me). I am considering Eaton made to order Springs, and they list one for Mach 1 with 351C and one for351 CJ for a 1972, and options for whether or not factory (HEAVY! ) AC equipped.  My H code, factory NON-AC,  has aftermarket Vintage Air with a very light compressor, a 4BBL aluminum intake, and headers. SO my guess is weight up front is about factory H code weight without A/C, and not as heavy as factory AC H codes for sure.  Also saw some springs at street and Track. I want ride height to be a touch higher than now in a perfect world.  So which Eaton spring option would you pick? I am thinking abou the CJ springs as they should be a bit stiffer, and i hope the ride height is correct OR the best Eaton Choice available. Would love some input please.

As for the front, both fenders are currently sitting at 25.5" at the centers over brand new 215/70-R14's.  I have used the Scott Drake 600lb front springs listed for 65-73's with much success in K code Mustangs and genuine 65 and 66 Shelbys with the 1" Shelby drop, and they are advertised as causing an 1" drop on their own vs. stock (who knows if they are just taking about 65's, or more or less saying it applies to all years). These springs made tires a close fit on the 65 Fastbacks, but they were great Kit overall. My hunch is the front is lower currently than would be almost any replacement spring. Front tires are brand new 215/70-14's properly inflated.  Both front fenders are approximately 25.5" currently.

Shocks will be premium shocks of some sort. Front shock options don't include my beloved Koni's unfortunately, but I know there are a few good options. I will use Bilsteins in the rear for sure.

Thanks for your help!

 

[Don C]

Stop buying springs that are for multiple years, body styles, and engines. Go to the Eaton Detroit Springs website and buy springs specifically for your car, you'll also have the options of various spring rates, and they have a lot of information and videos on their website

EATON Detroit Spring - The leading manufacturer of leaf and coil springs for the street rod and restoration industries

 

[Stanglover]

Stop buying springs that are for multiple years, body styles, and engines. Go to the Eaton Detroit Springs website and buy springs specifically for your car, you'll also have the options of various spring rates, and they have a lot of information and videos on their website

EATON Detroit Spring - The leading manufacturer of leaf and coil springs for the street rod and restoration industries

BRAVO Don. You're absolutely right. Go to the "horses mouth, not the horse ass" if you want the correct parts for these cars.

 

[Stanglover]

You might find the information in this tread useful assuming you have not seen it before. I have been there, done that and believe me, if they claim it fits 65-73, it doesn't, well not everything anyway. Stay away from front coils springs NOT specifically made for the 71-73's. Stay away from Grab-A-Track rear springs and that's from personal experience. I am NOT 100% sure who makes them, but I am pretty sure they are not made from a recommended spring grade steel. If they were, they would not have started to reverse curve.

As for ride height, my car with 235-60-R14 front and 245-60-R14 rear sits 25 1/2" and 26 1/4" center wheel arch. Eaton make 1" longer rear shackles if you want that little extra height. My shocks are KYB Gas-A-Just front and back, but Eaton suggest for KYB's the low pressure version. My front coils are the originals that are still in spec., the rears were just replaced with Eaton's Boss 351 153lb spring rate compare to the original 138lb s/r. I love the firm, but not bone jarring ride and along with an Addco 7/8" rear anti-sway bar, it handles and corners like it's on rails.

 https://7173mustangs.com/forums/topic/36373-an-interesting-and-informative-video-from-eaton-detroit-springs/?do=getNewComment

Pic is with new Eaton Boss 351 springs installed. While I can't seem to find it in my files, there is a pic of the 4.5leaf GAT's where the reversing can be seen P2, Dec 05 2020.

 

[Don C]

3rd post down on second page, shows the reverse on the GATs

An interesting and informative video from Eaton Detroit Springs - Suspension, Handling, Brakes, Wheels and Tires - 7173Mustangs.com

 

[griffbl]

Stop buying springs that are for multiple years, body styles, and engines. Go to the Eaton Detroit Springs website and buy springs specifically for your car, you'll also have the options of various spring rates, and they have a lot of information and videos on their website

EATON Detroit Spring - The leading manufacturer of leaf and coil springs for the street rod and restoration industries

Thanks for your response and opinion Don, and I will indeed do just as you prescribe.....as I mentioned I was considering that as the way to go.  All good!

 

[griffbl]

You might find the information in this tread useful assuming you have not seen it before. I have been there, done that and believe me, if they claim it fits 65-73, it doesn't, well not everything anyway. Stay away from front coils springs NOT specifically made for the 71-73's. Stay away from Grab-A-Track rear springs and that's from personal experience. I am NOT 100% sure who makes them, but I am pretty sure they are not made from a recommended spring grade steel. If they were, they would not have started to reverse curve.

As for ride height, my car with 235-60-R14 front and 245-60-R14 rear sits 25 1/2" and 26 1/4" center wheel arch. Eaton make 1" longer rear shackles if you want that little extra height. My shocks are KYB Gas-A-Just front and back, but Eaton suggest for KYB's the low pressure version. My front coils are the originals that are still in spec., the rears were just replaced with Eaton's Boss 351 153lb spring rate compare to the original 138lb s/r. I love the firm, but not bone jarring ride and along with an Addco 7/8" rear anti-sway bar, it handles and corners like it's on rails.

 https://7173mustangs.com/forums/topic/36373-an-interesting-and-informative-video-from-eaton-detroit-springs/?do=getNewComment

Pic is with new Eaton Boss 351 springs installed. While I can't seem to find it in my files, there is a pic of the 4.5leaf GAT's where the reversing can be seen P2, Dec 05 2020.

View attachment 50261

Great info Geoff, and especially when paired with your photo. I am down for firm but not Bone Jarring. I will buy the same springs  as did you for the rear. Also considering your suggestion as to a rear sway bar.  Our front fenders are at the same height, but my front tires are 1.4" greater in diameter, so my springs are definitely down some.  I will grab the front springs from Eaton also. Are you ok with the KYB shocks you have in the back?

 

[Stanglover]

Great info Geoff, and especially when paired with your photo. I am down for firm but not Bone Jarring. I will buy the same springs  as did you for the rear. Also considering your suggestion as to a rear sway bar.  Our front fenders are at the same height, but my front tires are 1.4" greater in diameter, so my springs are definitely down some.  I will grab the front springs from Eaton also. Are you ok with the KYB shocks you have in the back?

 Hi griffbl, I'm glad my experience has been able to assist. I will add that, as I don't know your mechanical knowledge and abilities, follow the advice on the videos re installation, torque specs etc. I learned a lot from these without doubt.

When you order, you will also need new U bolts and probably new shackles. I know Eaton sell the 1" longer ones through NPD, so I assume they sell them directly if you wanted the extra bit of lift. Don't forget, 1" at the rear (shackle) will not lift it that much at the wheel arch.

Also, you do not mention if your Mach 1 came with staggered shocks. If not, I think you'll need to order Addco's 3/4" sway bar for non-staggered shocks. The NEW REVISED 7/8" 990 bar is made for staggered only as far as I know. Addco's website has been down, but may be up by now, not checked. I would either call or email for that information unless someone else with this knowledge can chime in.  As for shocks, I find that the KYB Gas-a-Just can be a bit harsh if I hit a big bump. Nitrogen shocks do that it seems and may be the reason why Eaton suggest the low pressure ones ( I don't have the number in my mind). Actually, I find the ride with the Boss springs a little smoother than my 17 VW Passat over normal road conditions.

Going back to sway bars, If you're going to do the front end with stock type suspension and also depending on what has already been done, my suggestion would be to replace it all while you're in there. Again, don't waste your money as I did on a front end "kit". Be selective and buy US made Moog parts. This is what I would do if I were to do it again. The front anti-sway bar needs to match the rear. In my case, I have the Addco 1 1/8" front bar. I think a 3/4" rear would match with a 1" front bar. 

I can't think of anything else at this time, so maybe others can add to this. 

 

[griffbl]

Geoff-

I always order new Shackles when I buy springs from Eaton.  Stock ride will be fine, thanks.  I don't want much space above the tire to show, which is why I went as tall as I easily could with my tires. I COULD gain a bit of stance by going to 215/70-15's but that would necessitate a wheel change from my 14" magnums. I am dying to look over and try out some 15" magnum Legendary Wheel reproductions that are aluminum. I am a bit over zealous as to less weight, but it gives me something to think about  Being an H code, I do not think my shocks are staggered. I think? it took at least an M level engine code, or CJ in 1972, to get those staggered shocks.  I have a bunch of urethane / nylon bushings in a 1973 kit left over from another car (either an M code or a 429 car can't remember which). I am a big fan of Moog's quality. I may buy the QA1's that are featured by Eaton.....we will see. I DID watch the video. While I have bought piles of springs from Eaton, they are even better than I thought, and I DEFINITELY learned a bit more. Like you, I learn something new every day, because I unfortunately  make mistakes every day.! Maybe this time I will get the lesson first and the lesson afterwards. It is usually the reverse unfortunately!  

Best,

Brad

 

[Stanglover]

Geoff-

I always order new Shackles when I buy springs from Eaton.  Stock ride will be fine, thanks.  I don't want much space above the tire to show, which is why I went as tall as I easily could with my tires. I COULD gain a bit of stance by going to 215/70-15's but that would necessitate a wheel change from my 14" magnums. I am dying to look over and try out some 15" magnum Legendary Wheel reproductions that are aluminum. I am a bit over zealous as to less weight, but it gives me something to think about  Being an H code, I do not think my shocks are staggered. I think? it took at least an M level engine code, or CJ in 1972, to get those staggered shocks.  I have a bunch of urethane / nylon bushings in a 1973 kit left over from another car (either an M code or a 429 car can't remember which). I am a big fan of Moog's quality. I may buy the QA1's that are featured by Eaton.....we will see. I DID watch the video. While I have bought piles of springs from Eaton, they are even better than I thought, and I DEFINITELY learned a bit more. Like you, I learn something new every day, because I unfortunately  make mistakes every day.! Maybe this time I will get the lesson first and the lesson afterwards. It is usually the reverse unfortunately!  

Best,

Brad

 Brad, Sooooo, you've done this dance before eh!  As you have a H code, I doubt it has comp suspension and staggered shocks, unless it could be ordered specially in 72. I know my 72 H code did not, but my 72 Q code did, it was a 4 speed car that I should NEVER have sold, but that's a story for another day. 

On the subject of bushings, I think most will agree, the urethane type are squeaky and give a harsh ride. Personally, I prefer good 'ol rubber bushings.

Anyway for now, all the best with your car,

Geoff.

 

[Stanglover]

 I just thought of this regarding my front coil springs which are comp suspension rated. This may help you determine if your non-comp coils are really sagged. The spec overall unloaded height for this spring is 15". All the paint daubs are original. As you can see, my spring is 14 15/16" close enough for the girls I go with.

 

[timachone]

Geoff, 

have I seen right, there are three different paint color daubs on each front spring from yours? Pink, yellow and White? And the white ones are on the opposite?

 

[griffbl]

 Brad, Sooooo, you've done this dance before eh!  As you have a H code, I doubt it has comp suspension and staggered shocks, unless it could be ordered specially in 72. I know my 72 H code did not, but my 72 Q code did, it was a 4 speed car that I should NEVER have sold, but that's a story for another day. 

On the subject of bushings, I think most will agree, the urethane type are squeaky and give a harsh ride. Personally, I prefer good 'ol rubber bushings.

Anyway for now, all the best with your car,

Geoff.

 Geoff-

I had the urethane set, but your advice mirrors that of Eaton Detroit Springs....I could make it too harsh, and squeaks, well, I can do without those also. I had the poly stuff in the garage from another car or some such, as I don't ever remember buying them....but best to stick with rubber as you say.

Thanks!

Brad

 

[Carolina_Mountain_Mustangs]

I am an original owner of a 73 Mach 1 and the first week I owned it I added a booster coil spring on the rear shocks. The came new sitting low in the rear that is normal. The Osborne chassis assembly manual does give the Ford spec for ride height and is not measured to the body but to the chassis. I cannot locate my copy to give you a number. Leaf springs do not really wear out. If you have a spring shop where you live they can re arch them and will be same as new. Coil springs cannot be reworked if they have dropped.
If you go with gas filled shocks you will diffidently feel bumps way more harsh than standard shocks. I think the PO of my 73 vert put KYB on and it rattles your brain on a bump. Handles great but harsh ride.
This car still has the original springs and shocks on it and has the helper springs on the back. It has comp. suspension also. I think you said you have 14" magnums and the 71 & 72 came with 15" if ordered from factory. My 73 I ordered with the forged aluminum wheels and they are 14" only.

 

[griffbl]

I am an original owner of a 73 Mach 1 and the first week I owned it I added a booster coil spring on the rear shocks. The came new sitting low in the rear that is normal. The Osborne chassis assembly manual does give the Ford spec for ride height and is not measured to the body but to the chassis. I cannot locate my copy to give you a number. Leaf springs do not really wear out. If you have a spring shop where you live they can re arch them and will be same as new. Coil springs cannot be reworked if they have dropped.
If you go with gas filled shocks you will diffidently feel bumps way more harsh than standard shocks. I think the PO of my 73 vert put KYB on and it rattles your brain on a bump. Handles great but harsh ride.
This car still has the original springs and shocks on it and has the helper springs on the back. It has comp. suspension also. I think you said you have 14" magnums and the 71 & 72 came with 15" if ordered from factory. My 73 I ordered with the forged aluminum wheels and they are 14" only.

View attachment 50444

Thanks David...I sent you a note as to the Deck lid also! I alway liked the 14" forged aluminum wheels which were available on the 73's!

 

[Carolina_Mountain_Mustangs]

Got the note will see if someone can get the deck lid out for me. I have messed up shoulder and neck for right now.

 

[griffbl]

it is not at all urgent...i was curious as to price, and shipping, but mine really doesn't look that bad. the holes won't get wet as it is always garaged, and I will repair it when i do other body work...but i thought it might be a good option as you suggested.

Best,

Brad

 

[Stanglover]

Geoff, 

have I seen right, there are three different paint color daubs on each front spring from yours? Pink, yellow and White? And the white ones are on the opposite?

 You're almost correct, they are pink, gold and white. And yes, on this one the white was opposite, no idea why unless it was in the QC process. I did refinish the springs before I put them back in and sort of duplicated the paint daubs.

 

[timachone]

Thank you, that looks really good! I will it do your way too - new springs, shocks (you have also KYB, right?), control arms, perches, hardware etc. is ready. I have only to look after my specific colors on the springs in my book - could have been different. Did you leave the control arms black? I am not sure if I should let them black too or give the upper a pure steel finish and the lower a half way black as it was originally on our cars...  :classic_dry: