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Old May 14, 2014 | 10:27 AM
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Default rear spring rate

Hey all,

I changed my back to coil overs on my 4th gen, tried the 100# spring and the 125# spring and it still sits really low. I'm about to try the 150# but I don't want it to be rock hard as I DD this thing a lot.
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Old May 14, 2014 | 10:34 AM
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Originally Posted by 2000dreambird
Hey all,

I changed my back to coil overs on my 4th gen, tried the 100# spring and the 125# spring and it still sits really low. I'm about to try the 150# but I don't want it to be rock hard as I DD this thing a lot.
Our BMR rear lowering springs are rated at 160lbs so a coil-over springs with a 150lb spring rate should be a very good option for you. It will still have a nice ride quality and it should fix the ride height issues you are running into.
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Old May 14, 2014 | 02:11 PM
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Originally Posted by BMR Sales2
Our BMR rear lowering springs are rated at 160lbs so a coil-over springs with a 150lb spring rate should be a very good option for you. It will still have a nice ride quality and it should fix the ride height issues you are running into.
Thanks so much, first helpful answer I've gotten.
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Old May 14, 2014 | 03:20 PM
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Originally Posted by 2000dreambird
Thanks so much, first helpful answer I've gotten.
Not a problem. The tough thing for you is that the coil-over springs are going to be sold in 25lb increments so if the 150lb springs are still too soft (which I don't think will be an issue at all) you will need to step up to the 175lb springs.
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Old May 14, 2014 | 06:07 PM
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Originally Posted by 2000dreambird
Hey all,

I changed my back to coil overs on my 4th gen, tried the 100# spring and the 125# spring and it still sits really low. I'm about to try the 150# but I don't want it to be rock hard as I DD this thing a lot.
You need to be a little more specific with what you have tried.
Since you said you have coilovers have you tried adjusting the height? Are the springs you are buying the correct length? There is more to ride height than just spring rate, stock springs are a soft ~114lbs/in but have a really high ride height for example.
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Old May 14, 2014 | 11:09 PM
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Exactly. Are you sagging because you need a 14" spring and you have a 12"? Do you have the coilovers set too low?

The 125s should be a decent spring rate on the car with coilovers.
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Old May 15, 2014 | 12:41 AM
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Keep in mind that with the coilovers in the rear, the springs have been moved forward on to the shocks which means you effective spring rate will actually be lower, so you 150 lb.in. spring rate is probably more like 125 lb.in. with the spring moved forward in front of the axle tubes.
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Old May 16, 2014 | 03:23 AM
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It's currently sitting on 125lb, 14" springs.

Adjustment for ride hight is maxed out, he's sending me the 150lb, 14" to install. Should have them Monday.

Right now I have about 1.5" height from wheel to fender lip on drivers side, but only ~1" on the passenger side (passenger side has always sagged for some reason).
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Old May 16, 2014 | 08:34 AM
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Originally Posted by 2000dreambird
It's currently sitting on 125lb, 14" springs.

Adjustment for ride hight is maxed out, he's sending me the 150lb, 14" to install. Should have them Monday.

Right now I have about 1.5" height from wheel to fender lip on drivers side, but only ~1" on the passenger side (passenger side has always sagged for some reason).
Since you are running a 14" long spring and the ride height adjustments are adjusted all the way up on the body of the coil-over the spring rates are definitely what the issue is. The 150lb springs will definitely help out with the ride height, once you get them installed let us know how it works out for you.
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Old May 21, 2014 | 01:11 AM
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So I got the 150lb springs in and the ride height is great. And not to stiff. Only problem is that the rear passenger side still sages lower than the rest. It takes about 1.5" of adjustment more on that side to side even.
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