#21  
Old 10-28-2020, 02:06 AM
Schurkey Schurkey is offline
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Quote:
Originally Posted by leeklm View Post
Often times we end up making these cars lighter with aluminum heads, intakes, removing AC, etc. End result is now the front springs are too stiff! That happened on my 73 GTO and ended up installing moog springs listed for a 6cyl car to level it back out
RIDE HEIGHT can be achieved either of two ways.
Short, stiff springs, or
Tall, soft springs.

GM, Ford, Chrysler, AMC...pretty much every mass-market car--has springs that are too tall, and too soft. "6-cylinder" springs might even be worse. Mopar used to recommend 6-cylinder torsion bars for drag cars--soft spring rate, cranked-up at the adjuster to get ride height. Lots of stored energy in those springs for drag-race weight transfer.

Removing weight from the front makes the front end even higher because the tall-soft springs aren't compressed as far.

The real issue is the springs are not too stiff, they're too tall. In most cases, they're not stiff enough!

Short, stiff springs are exactly what street-driven older cars need. The trick is to get the ride-height you want using the right combination of stiffness and height on the springs.

  #22  
Old 10-28-2020, 02:54 AM
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Nothing wrong with spacers under the rear coils. I had 1" spacers within a week of taking delivery of my '67 GTO in March of '67 until about 2000 when I swapped over to air bags. Car was fine and the spacers do not alter the stock ride since the same spring rate and travel are preserved. I went with the bags to carry a trunk full of stuff to the shows along with passengers in the rear seat. The air bag ride is acceptable although compression is definitely no longer linear since the bag gets stiff really fast when compressed by a bump or through a dip. Have three cars with bags and all three systems require being topped off with additional air every month. The slight air loss isn't a big thing, but pressure going from 12 pounds to 8 has the rear end dropping slightly down.

My new addition is the '65 Catalina wagon that came with some cheap spring wedges installed between the stock coils. The plan is to go for new +1 or possibly +2 heavy duty springs from Eaton since the stock springs are also mushy so just using a spacer underneath won't cure that.

FWIW installing aluminum heads raised the front of my '67 GTO exactly an inch over the cast iron head height.

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  #23  
Old 10-28-2020, 06:58 AM
gtospieg gtospieg is offline
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jimib...The difference in springs from 66 to 67....67 springs have pigtails top and bottom, 66 springs do not have a pigtail at the top. So if you had a 66 spring that was too tall it could be trimmed to adjust ride height. I hope that helps.

  #24  
Old 10-28-2020, 09:20 PM
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The concept of lowering a vehicle seems to be popular; I'm not sure why, but my assumption is improved handling. For the most part, I prefer to drive in a straight line and l like some ground clearance. Also, a car with a bit of lift (front and rear) has a somewhat of an "aggressive" appearance which I find appealing. I like the front end height of my ride (see pic), I just need the rear to match that height or a 1/2 inch higher in the rear.

I have read through every single post and have been educated on "spacers", airbags", "air shocks" and "custom springs"; all great infor. I like the advice from our member here, "lust4speed". Sir; I've done a search on "Eaton" and came across the web site https://www.eatondetroitspring.com/. This allows the car owner to customize the spring as in "heavy or stardard duty", then options from -1 inch below stock ride to stock ride and up to +2 inchs above stock ride height. I think I should order a spring the is +2 inches above stock and this may match the front end. If not, then I could add mild spacers or airbags.

The GTO picture I've included in the post is one I Googled. This is the look I desire.

Thank you to all
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  #25  
Old 10-28-2020, 11:04 PM
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Can’t you just run wagon springs in the back and solve all the problems easily? I did this on my other ‘69 A Body because I wanted a slight rake. I tried the HD springs for my year first and wasn’t happy. It was just a stiffer same height ride. The wagon springs gave me a comfortable spring rate with the added height I wanted.

Moog 5235’s look to be the ones from ‘66

If you look them up on Amazon you can read a review someone did where they used these springs for that exact same reason (their photos below). If that doesn’t give you the look you want then I’d guess you have the wrong springs up front or possibly need to mod them to offset your change in weight up there. Although, I’d really guess the taller springs in the back will transfer some of that load back up front and drop it a little as it has that “engine-less” look already.
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  #26  
Old 10-28-2020, 11:13 PM
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Tim Corcoran Tim Corcoran is offline
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Your springs are either the wrong springs for your car or they are worn out and tired. Order new springs from a spring company and request 1 inch taller than stock. That should sit it just about right. As for the front springs you have have the wrong springs in there if the front is too high. The rear springs are very easy to change the fronts are a little more work.

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  #27  
Old 10-29-2020, 01:30 AM
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And remember that the "A-body" rear suspension design doesn't take well to being lifted. Heavy acceleration with a lifted rear causes traction problems, potentially of a severe nature.

  #28  
Old 10-29-2020, 08:16 AM
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Jimi, I would start by replacing all 4 of those springs. It looks like you have no engine under the hood and and engine in the trunk. That rear sag is too much to fix with spacers, it definitely needs springs. I have 13 yr old springs in my car with either 1.5 or 2" spacers and have had no issues in that time and 35k+ miles. Somebody with a same yr car should tell you which springs to get.

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  #29  
Old 10-29-2020, 08:33 AM
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I've installed Moog "cargo coils" in a few of my GM cars, and they provide a normal ride height and the ability to maintain normal ride height with weight in the car.
Put them on a couple of cadillacs I drove and got rid of the air ride, which consisted of air shocks, compressor, ride height sensor, which always was glitchy.

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  #30  
Old 10-29-2020, 10:16 AM
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Quote:
Originally Posted by Entropy11 View Post
Can’t you just run wagon springs in the back and solve all the problems easily? I did this on my other ‘69 A Body because I wanted a slight rake. I tried the HD springs for my year first and wasn’t happy. It was just a stiffer same height ride. The wagon springs gave me a comfortable spring rate with the added height I wanted.

Moog 5235’s look to be the ones from ‘66

If you look them up on Amazon you can read a review someone did where they used these springs for that exact same reason (their photos below). If that doesn’t give you the look you want then I’d guess you have the wrong springs up front or possibly need to mod them to offset your change in weight up there. Although, I’d really guess the taller springs in the back will transfer some of that load back up front and drop it a little as it has that “engine-less” look already.
I like this idea, thank you.

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  #31  
Old 10-29-2020, 11:07 AM
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Eaton Detroit Spring manufactures springs in the USA for specific year/make/model using factory blueprints. On their website, they list factory height, +1", +2", in standard duty or heavy duty, but they can also make custom heights/rates as well. +1" in the rear gave my '67 a very slight rake, which I personally like much better than the factory stance (rear a little lower than the front). IIRC they cost just under $200. To figure out exactly what you need given your specific situation (assuming you will keep the existing front springs), jack up the rear of the car to factory height, then simply adjust and measure how much higher or lower you want it.
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Last edited by Gator67; 10-29-2020 at 11:17 AM.
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  #32  
Old 10-29-2020, 11:13 AM
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Quote:
Originally Posted by jimib View Post
I like this idea, thank you.
FWIW, I have used wagon springs before in my A bodied cars. It will raise the rear up, and not give you the harsh ride associated with air bags. Adding air bags really raises the spring rate, and can cause a lot stiffer ride when added to a steel spring already. It probably increases the spring rate 1/3 over just the steel spring by itself.

Air shocks are a band aid, and when they are holding the majority of the weight of car up will rip out the upper shock mount eventually. I've seen it happen too many times to count.

Ideally I like air bags without the steel spring, but it's not cheap to convert to air springs as the only suspension holding the car up, but IMO it is worth the effort. Infinitely adjustable, with a very nice ride as compared to any of the alternatives. As I age, my tastes change, as far as bone jarring suspensions.

I fabricated rear air ride in my 1993 K3500 dually, one of the best modifications I've made to my vehicles in over half a century. OTR trucks have been using it (air ride) to haul heavy loads for decades, and having driven 18 wheelers in the past I could plainly see the advantages of air ride over conventional steel springs. Not for everyone, but it worked well for me.

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  #33  
Old 10-29-2020, 12:24 PM
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Quote:
Originally Posted by Gator67 View Post
jack up the rear of the car to factory height, then simply adjust and measure how much higher or lower you want it.
Make sure you determine "factory height" by using the measurement procedure described in the "factory" service manual.

In other words, a tape-measure on the fender lip to ground isn't proper or accurate, and neither is looking at the "rake".

The way the car "sits" as judged by fender position is going to be affected by a bunch of variables, including but not limited to tire pressure, tire size, body-to-frame cushion condition...and we haven't even considered the springs yet.

Again, increasing the ride-height on the A-body rear suspension leads to traction problems.

  #34  
Old 10-29-2020, 01:05 PM
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That Eaton Detroit Spring company seems to have everything a person could want as far as springs.

  #35  
Old 10-29-2020, 03:17 PM
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Wagon springs in mine - still no interior in it yet, empty trunk and gas tank too.
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  #36  
Old 10-29-2020, 08:42 PM
gtospieg gtospieg is offline
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jimib...If you use the '66 wagon springs(Moog 5235 $117.81 on Amazon...$81.79 on Rock Auto) and they end up too high you will be able to cut the top because they don't have the pigtail like '67.


Last edited by gtospieg; 10-29-2020 at 08:50 PM.
  #37  
Old 10-29-2020, 08:52 PM
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I used station wagon springs in my '65 and the rear ride height is perfect with a slight rake relative to the front end.

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