UMI lowering springs; still suck? UMI or another brand?

arlowf

Apprentice
Thread starter
Feb 11, 2022
81
8
I agree with Northernregal . This is not the way this works, unfortunately. You're making the same assumption that I did the 1st time I tried adjusting ride height with different springs from different engine setups. I tried two different sets of springs and ended up putting the original saggy springs back in. And they were in that car until it's untimely demise. That car had varying front end weights as the power plant changes occurred. And FWIW, as the heavier the front end got, the better the stance - and the handling didn't get worse. Of course this is my opinion, but I can safely say that car was glued to the road as compared to my MC.

In my current car I have V6 springs from a V6 car with AC and they look original for whatever that's worth. I've deleted all of the heating and a/c system including inside the car. I've added a 4L80 (+100lbs), 4.5 gallons of ATF (20+ lbs), T6 turbo (+50lbs), piping/intercooler/piping/30x12 trans cooler/etc. (+40-50lbs) - and it rides great in straight line, but not much for handling with skinnies on the front. Point being, the V6 springs are adequate and my ride height is not too low. You can find pics of the stance here if you look.



I agree 200% with what Jared is indicating. I was told this by my local spring shop guy, that was a genuine hotrodder in his younger days. He explained this to me when I was swapping springs and the problems caused by cutting springs and how the results are somewhat of a crap shoot. Others might disagree, but ......


arlowf This thread is describing every reason why guys swap to coil overs. Every coil over manufacturer has various springs for rate and height specs. Regarding your shop doing the work and multiple calls to UMI, I'd be concerned that you might at the point where you're wearing them out. I know when this happens to me (similar business), I get to the point of telling the customer 'yes' to every question just to get them out the door. I know that isn't the right thing to do, but when someone isn't picking up what I'm putting down, then it's time for me to move on.

Either cut the springs as UMI has suggested or save for an a-arm/coil over package - my best advice.
Just so everyone knows I wound up cutting 1.5 coils off the 2" lowering springs and after a week they are sitting about where I want it. It'll probably settle more. I have just enough room for 28.5 inch tires.
 
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Built6spdMCSS

Comic Book Super Hero
Jun 15, 2012
2,708
113
Florida Beach
I read this whole thing, because I'm looking to drop my SS down. I currently have the Eibach Pro Kit that I installed in Dec 2010 so they are settled, took this pic yesterday..

20221105_101510.jpg


As anyone can see, I have room to play with here. I'm actually lower than where it should be, some wore out body bushings that I'm looking to fix so this side will raise up probably 1/2".
Now the technical... Front is lighter than stock setup would have been. Engine is an Ironblock 6.0l, that is lighter than the 305 that came out, T56 with the Clutch Assembly is lighter than the 2004R with Convertor, and the Battery is in the Trunk ontop of the Rear Axle area, passengers side. No AC, so definitely lighter in the front than normal. Rear is heavier with the Battery. Car on scale full tank of gas is 3500lbs.

So I'm looking to lower it once I put in the solid Body Bushings. Could very easily cut the Front Coils down since it's easy to do with how they are shaped. Would have to buy a Rear Coil Spring Set since the rolled ends are needed to sit right on the Axle and the upper pocket. I read this whole thread to see what option for that is good.

Really curious to how someone is cutting the rear spring down..🤔
 
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Texas82GP

Just-a-worm
Apr 3, 2015
7,729
113
Spring, Texas
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Built6spdMCSS

Comic Book Super Hero
Jun 15, 2012
2,708
113
Florida Beach
I think the ones I have in the back are rubber like that already, been a while since I have had them out just remember I had to grease them one day because of this horrendous squeaking noise in the back and that was the culprit.
 
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81cutlass

Comic Book Super Hero
Feb 16, 2009
4,362
113
Western MN
Nobody really cuts the dual pigtail rear springs in my knowledge.

Stock A body springs, moog 5401, 5409, 5413, seem to be the way to go to lower the backs. I have 5401 in my light cutlass and 5409 in my heavier 2+2. I'm sure there are some applications like a gutted fiberglass malibu where you might need something lighter than a 5401. Generally Moog A body springs are stiffer and shorter than a G body.

Not sure how much handling improvement there is on the rear with a stiffer spring than you'd get with a Moog A body spring?

A 9" also lifts the back at least 1/2" due to the tube diameter increase over a 7.5/8.5.
 
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Built6spdMCSS

Comic Book Super Hero
Jun 15, 2012
2,708
113
Florida Beach
Nobody really cuts the dual pigtail rear springs in my knowledge.
That's why it had me wondering..

A 9" also lifts the back at least 1/2" due to the tube diameter increase over a 7.5/8.5.
Yup that's where I'm at with the 9". The MOOG 5660 was mentioned to me and by numbers the UMI ones are lower.

I need to get a measurement of my current compressed rears and that will help me with a baseline.
 

UC645

G-Body Guru
Apr 20, 2020
874
93
Kittanning, Pa
I read this whole thing, because I'm looking to drop my SS down. I currently have the Eibach Pro Kit that I installed in Dec 2010 so they are settled, took this pic yesterday..

View attachment 210479

As anyone can see, I have room to play with here. I'm actually lower than where it should be, some wore out body bushings that I'm looking to fix so this side will raise up probably 1/2".
Now the technical... Front is lighter than stock setup would have been. Engine is an Ironblock 6.0l, that is lighter than the 305 that came out, T56 with the Clutch Assembly is lighter than the 2004R with Convertor, and the Battery is in the Trunk ontop of the Rear Axle area, passengers side. No AC, so definitely lighter in the front than normal. Rear is heavier with the Battery. Car on scale full tank of gas is 3500lbs.

So I'm looking to lower it once I put in the solid Body Bushings. Could very easily cut the Front Coils down since it's easy to do with how they are shaped. Would have to buy a Rear Coil Spring Set since the rolled ends are needed to sit right on the Axle and the upper pocket. I read this whole thread to see what option for that is good.

Really curious to how someone is cutting the rear spring down..🤔
Another option is to switch to 5 inch coil springs in the rear using upper locators like these:
C9BBBA99-0437-4B43-8837-0B7E88F94A4B.jpeg


Add in a set of 5 inch perches (I got both from Allstar Performance) and a set of 5 inch coils from Lamdrum or a similar company, and you’ll have a ton of options. I did this for exhaust clearance reasons mainly, and haven’t gotten a chance to run it on the road yet, but I can say a 13 inch tall spring with a 150 pound per inch spring rate is a tad on the short side, as the springs fall out at full suspension droop.
 
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Streetbu

Know it all, that doesn't
May 22, 2011
3,447
113
Central NY
I bought a set of rear springs from Suspension Techniques, a LONG time ago and they happen to hit my desired ride height perfectly. I can measure again, but IIRC the rear is at 25.5" to the wheel lip
 
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