So I just finished installing a UMI Performance suspension on my Cutlass. I went for all stock-height stuff, including front upper and lower a-arms, stock replacement springs, etc. There are two things I did which are different than the stock setup - 1) beefier sway bar (1.25") up front which is UMI's smaller bar and 2) 1/2" taller ball joints on the upper a-arms. I kept the original spindles which were in excellent shape, surprisingly.

It appears to me to be riding a bit higher in the front than before. Not by much, but enough that it bothers me. If I had to guess, I'd say about an inch at the front bumper. The back end looks just like it did before but also got the full UMI treatment.

What are my options here? I want to lower the nose a little, but 2 inch drop spindles would likely be way too much. I know I could get lowering springs from UMI as well, but again, not sure if that will also be too much. Is there something I am not thinking of?

Note that I haven't had it properly aligned yet (did the string trick so that I could get it close enough for a test drive), so that may change things a bit. It handles really, really well from the 1.5 mile test drive I put on it, but if I am going to swap spindles or whatever, I wanted to do that before aligning it.

 

I am always concerned when I read "stock-height" as there are so many different springs out there with different spring rates, load ratings, etc. that will make the car sit at different heights. This is why the manufacturer had a different springs for different applications so that the variations in vehicle weights due to engine size, AC vs no AC, HD vs standard suspension, etc were taken into account.

So the bottom line is I think your springs are too tall.

 

New springs will need time to settle and almost always your car will sit high initially.

I would wait at least one month.

Rick

 

X2 on the above. Was the suspension hardware torqued with weight on the wheels?

 

Coil overs - adjustable
The 2" drop just changes the geometry - adjust with coil overs

 

Generally, I'd agree with you on this. But UMI is a company with a decent history in GM A-body suspensions. I went for springs that they listed as stock height for a cast iron-headed 350 or aluminum headed 455. Definitely, not saying they can't make mistakes, but this isn't some fly-by-night that resells random "compatible" components, either.

Ok, this is something I had never heard of, but I've usually dealt with cars with struts... This may be exactly my problem. It has only been sitting on the suspension since earlier this week. Thanks for this info!

The upper and lower control arms were left loose and torqued with the weight on them per UMI's advice (and the service manual). I did torque the sway bar mounts, end links, tie rods and spindle nut to spec up on the stands, but is there any reason I shouldn't have? Clearly not with the spindle nut because I have to spin the tire to torque it according to service manual specs, but anything else I should've left loose?

This will be my backup plan. I am going to call the manufacturer as well, but if I can't solve it any other way, I'll go to adjustable coil-overs.


I'll see if I can grab some pictures, but this is really a minimal difference. I haven't called UMI yet, but I know they put a lot of effort in R&D into the suspension geometry. Most non-car-guy types would never notice the difference, but I've driven it for a few years before this. (oh and I am kinda picky ).

 

I completed a full suspension rebuild last winter using UMI stock springs (front & rear), and new UMI rear upper & lower control arms UMI rear sway bar. I used reused my stock OEM front UCA & LCA. I have Bilstein on front and Monroe coil overs on the rear. Ball joints were Moog. All part numbers are listed in the link:

https://classicoldsmobile.com/forums...ension-141577/

Profile photo Post #2

 

I hear ya, but the MOOG catalog lists 5 different springs for the different variations of the same model vehicle. Not saying that UMI doesn't know what they're doing but I did notice that Norm's car appears to be much higher both front and rear than my car.





Here's a comparison shot of Norm's car with UMI springs from his post referenced above and my car with Moog springs. The rear of mine sits a bit higher than it should but the front is the correct ride height per the CSM.

 

Floor is perfectly level. 15" wheels, 245/45R15 tires. Measurements (below) are exactly as stated +/- 1/16".
EDIT: Corrected tire size. Thanks Kenneth.

 

The height of my car behind the rear wheel is similar at 14.5" (I know mine is a bit too high), but my front end is 2.5-3" lower. I have 25.5" tall tires (245-60-15).

I thought maybe some of the difference was tire height so I was gonna look up your tire height but something ain't right about what you posted.

 

When you figure it out let me know.

 

Ah! I fat fingered the tire size. You’re right.
245/45R15
Ooops

 

Wow, Kenneth. Thanks for sharing that info and the pics. You may be on to something here... I will do some measurements, too, but worst-case I can go back to UMI about the spring height. I do want to let the car sit on the suspension for a bit though and see if that changes things at all. I guess there'd be no major problem with running a different spring or even coil overs...


Great pic with the heights drawn on there. And the thread for your suspension build was awesome - wish I had seen it earlier! I used that same "spatula style" spring compressor and it kept getting wedged and causing problems... I really thought it was user error and I just didn't know how to get it positioned right, LOL. Anyway, I am going to go measure my Cutlass's ride height tomorrow, but I have a relatively small garage, so I'll probably have to find a flat parking lot or something to get a decent picture.

I am running 225/70R14's on the stock, original rims from my car. I had 245/60R14 on there before the suspension upgrades as well, but while I did the suspension, I saw that they were badly dry-rotted and much older than I realized. The 225's a really a stop-gap as I want to get different wheels at some point (though I have to admit, I like the color-matched original look so much). Anyhow, that's going to affect ride height as well because the tires will be a bit taller than what I had before.

Thanks again!
-Mark

 

The springs will definitely settle. I put a 3” lift kit on my wife's jeep when we first got it. After about 6 months the front end had dropped almost an inch. I ended up having to put in 3/4” spring spacers to level it back out. Now it’s perfect. These were good Quality springs too. So if yours settle an inch you should be fine.

 

I have a set of UMI 1" front lowering coils for sale if you're interested.