Incorrect ride height on '73 due to coil springs

[GT73]

I just installed new Moog front coil springs, Munroe shocks and polyurethane bushings on my '73 Cutlass Supreme 2 door.

The car now sits 2 inches too high in the front.

I used Moog regular coil springs (#578), no air conditioning, not heavy duty. Used these because the car never came with air and want to keep it at the correct ride height of 10 3/8" as recommended in the Olds '73 Service Manual.

Probably due to one of 3 possible things...
- they are not the correct springs (Moog generic springs not specific enough)
- front end is lighter due to aluminum intake, rad, water pump, polyurethane bushings need to settle
- installed incorrectly (but I doubt this one)

Anyone else have similar problems when they changed their springs?

[76HOProposal]

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[GT73]

Thanks for the reply 76HO.

I was told to wait for the springs to settle from many others as well. Its just that 2 inches seems like a lot for just settling. Was thinking of having them cut down in order to compensate for the loss of weight due to the aluminum parts.

As for the bushings, they are Moog polyurethane, not polygraphite, will have to live with the squeaks I guess?

[John inNH]

My '75 has the same issue, heavy-duty Moog springs up front, and cargo coil's in the rear. The front sits about 2" too high. And they have been in the car for about 1 year, so I think the've settled. I put airbags in the rear to level the car, but as soon as I stop driving it for winter, I'm either replacing the springs with standard duty springs, or more likely haveing the coils cut down some.

John

[Team11HurstOlds]

This is a common problem as there are no companies out there that make the correct ride height springs. The springs will never settle down to the correct height even if they are new they will drop centimeters at best not inches. I have had this problem with every spring company out there. Your best bet is to order heavy duty springs and cut off a coil to have the car sit correctly or have a custom set of springs made like I did. The aluminum intake, radiator, water pump etc. is not enough weight to notice a difference in ride height. I have aluminum heads, battery, relocated to trunk, no A/C, fiberglass hood, misc. light weight parts on my pro touring Olds and the nose didn't budge! Of course driving it you will notice the weight loss. It's all in the springs and you'll be waiting 10 years before those things sag down to where you want the car to sit.

[ragz442]

Did you tighten the c/arms with the car jacked up? If so, loosen them up on the ground, jounce the front end a few times and tighten them up.......may help.

[76HOProposal]

erased

[73hurst]

I don't know for sure, but I've been told that Moog was the original supplier of springs. I'm wondering how those cargo coils worked out? I put new springs under my '70 convertible. The front ride height was fine, but the rear end dragged butt. I took them back and tried three other sets of springs, none of which seemed to have the correct ride height, all seemed to sag too much. In an effort to fix the problem, I probably went too far, and have a set of station wagon cargo coils in there now. I'm restoring the car, so have the body off, so don't know what it will be like when the springs get loaded. I'm thinking I might have wasted my money, as I needed a coil spring compressor to get them in. Never had that with any other set of rear springs, so am thinking they won't work. Finally, I've heard that places like Eaton Detroit Spring will make a set to your specs. Tell them the vehicle, options etc. and the ride height you want, and they'll set you up. There is a difference in the number of coils and diameter of the wire from stock.

Pete

[GT73]

Went to a spring specialist, they recommend trying Moog #5402 front coil springs. They will be installed on Wednesday, hoping these will drop the car 1.5 inches.

What he looked up in his book was the actual load capacity of the springs, compared to the one's installed on the car now.

Moog part #578 are recommended for my car... '73 with a 455, no air, non-heavy duty, but due to decreased weight over the years... aluminum intake, rocker covers, water pump, rad, headers, etc. we need to go with a spring with less load capacity, thus trying the #5402's which are for a 350.

73HO thanks for the advice with cutting, hoping that won't be necessary, doing so is risky business and part science... load weight, height, etc.

Torching (heating up) springs in order for them to drop is another trick, but lessens the integrity of the spring itself. This is not recommended.

73Hurst, your correct, Eaton Detroit Spring are probably the best supplier's of springs, period. Their website claims that GM and Ford use them directly and they are very friendly and knowledgable. I wouldn't doubt that this is who Fusick and the other vendors use for springs.

Make sure that the spring is specifically for your car... year, model, body style, engine, air or no air, heavy duty or not.
http://www.car-stuff.com/performance/quote.php?make=20&year=1973&model=213&brand=4543&part_name=38&skipped=true

Without proper ride height the car will either float or bottom out. When its too high, it is nearly impossible to properly align the car, thus causing tread wear problems later. Also, the control arms will not be parallel to the road causing the car to thud or bounce over bumps.

Its just not about looks, but also aerodynamics and handling. Installing the correct springs is crucial.

[black_bishop]

sorry to bring back an old thread but how did these springs work out for ya?

[GT73]

Hey Black, thanks for asking. The springs as expected, settled after driving on them for a couple of weeks. Lesson learned, get springs that match your car exactly, watch out for the stock number Moog uses.

Go for variable rate springs in the rear. Be patient and expect the springs to drop about an inch after a few weeks. If they sit higher than an inch then get lighter rated springs.