Why change your suspension?

[Dark Magenta]

But I'm not. I'm hoping to understand the rationale of those that have lowered theirs.

I was a mini-truck guy. I've owned 4 Nissan D21 Hardbodys and was too poor to play with the suspension, though I spent way too many hours on nissanminisdotcom or whatever it was dreaming about it and planning it. Now my 3 kids are adults and I can play. I'm still not used to having the $ that grown kids affords, so instead of getting my dream truck (Datsun 620) and going wild with it, I got something cheap and started tinkering. I may never actually follow through with adjustable suspension (damn student loans), but at least I lowered something.

[Eggman]

I'll give some pros and cons for suspension modifications from my limited understanding in hopes to get a better focus on some concerns I have.

I understand that designing a car is an exercise in compromise. After all, what car does it all and does it all good? Not knowing the design process of the manufacturer, each modification not only changes the one single element but potentially several others. In other words, change one thing, affect ten others.

A anti-sway bar helps keep the car level while turning, giving the driver confidence while going around corners. However, this leads to the likelihood that the inside wheel will tend to lift up off the road, diminishing available traction while cornering. This is arguably minimized as most of the weight and therefore available traction is transferred to the outside wheel.

Suspension height changes (lowering or raising) have much greater impact to the rest of the suspension and drivetrain:
1. Bushings that have settled into whatever position are now operating at a range out of the original specs. I see this leading to a looser suspension.
2. Front-end drive components such as the constant-velocity (CV) joints have a similar problem. Though CV joints have greater flexibility than Universal joints by design, they still have their limitations. Making CV joints operate out of their normal range increases the chances that the protective boot will fail, leading to an early failure of the joint itself. However, lowering might just improve this - rather than increase the CV joint angles, it might straighten things out.
3. Same goes for alignment. There was a post here on the forum some years ago where a forum member stated that lowering will make rear-end alignment problems worse. I tend to agree with that, whether the rear axle had alignment problems to begin with or not. I don't think anyone has posted alignment results that say otherwise. At least the front-end is somewhat adjustable - the Mirage rear axle is fixed.
4. The suspension will be more likely to 'bottom out', hitting against the bump stops. This is exacerbated with softer spring rates. Lowering reduces the overall travel available making bottoming out more likely and has been reported by forum members. And who is going to lower their Mirage with the factory skinny tires? With larger (wider) tires, now there are interference problems with hitting the fenders, inner fender wells or other suspension components.


So maybe I'm seeing this wrong but from what I can tell lowering has a greater impact than bolting on a anti-sway bar.

[Dark Magenta]

I'll give some pros and cons for suspension modifications from my limited understanding in hopes to get a better focus on some concerns I have.

I understand that designing a car is an exercise in compromise. After all, what car does it all and does it all good? Not knowing the design process of the manufacturer, each modification not only changes the one single element but potentially several others. In other words, change one thing, affect ten others.

A anti-sway bar helps keep the car level while turning, giving the driver confidence while going around corners. However, this leads to the likelihood that the inside wheel will tend to lift up off the road, diminishing available traction while cornering. This is arguably minimized as most of the weight and therefore available traction is transferred to the outside wheel.

Suspension height changes (lowering or raising) have much greater impact to the rest of the suspension and drivetrain:
1. Bushings that have settled into whatever position are now operating at a range out of the original specs. I see this leading to a looser suspension.
2. Front-end drive components such as the constant-velocity (CV) joints have a similar problem. Though CV joints have greater flexibility than Universal joints by design, they still have their limitations. Making CV joints operate out of their normal range increases the chances that the protective boot will fail, leading to an early failure of the joint itself. However, lowering might just improve this - rather than increase the CV joint angles, it might straighten things out.
3. Same goes for alignment. There was a post here on the forum some years ago where a forum member stated that lowering will make rear-end alignment problems worse. I tend to agree with that, whether the rear axle had alignment problems to begin with or not. I don't think anyone has posted alignment results that say otherwise. At least the front-end is somewhat adjustable - the Mirage rear axle is fixed.
4. The suspension will be more likely to 'bottom out', hitting against the bump stops. This is exacerbated with softer spring rates. Lowering reduces the overall travel available making bottoming out more likely and has been reported by forum members. And who is going to lower their Mirage with the factory skinny tires? With larger (wider) tires, now there are interference problems with hitting the fenders, inner fender wells or other suspension components.


So maybe I'm seeing this wrong but from what I can tell lowering has a greater impact than bolting on a anti-sway bar.

I can't speak to 1 and 2.
3 and 4: I believe the lowering springs are stiffer. While there is less suspension travel available, I don't believe I have bottomed out the rear, even with 3 adults in the car plus traveling supplies. (I believe I have bottomed out the front) I got my alignment checked before and after lowering, and yes, the alignment was a little worse after. I now have 2 sets of skinny tires and I feel chamber being off on 165s is something I can live with.

[Fummins]

Stop sounding like my dad! He always used to try and talk me out of buying ridiculous vehicles or doing anything to a perfectly functioning car/truck. I have slowly been starting to take some of that advice. No more trucks so high the steering column wears out from pulling yourself in by grabbing the steering wheel or cars so low you bottom out pulling out of parking lots. I do miss them all though.

I will agree, lowering probably does nothing to improve handling to it's full potential unless the shocks and coils are designed, adjusted and valved for that car. But I'd assume stiffer suspension on these cars would reduce body roll some, making it feel better?

1. This is true. Some bushings can be loosened off and tightened while car has weight on them helping to avoid that binding/extra travel in them. But some can't like the bushing in the rear of the front control arms.
2.I personally would lower mine just cause they look good lowered knowing it'd probably ride like crap now. I do plan to buy a daox bar in the future but really haven't felt a need for one. I figure/hope the longer I wait the more I'll appreciate how much a sway bar helps when I do get one. Likely next year? I'd happily be a shill if given one

Oh and straight cv axle are just as bad if not worse than extreme angles. Lowering will straighten the shaft and shorten it making it bind in extreme cases. I witnessed that first hand in a guys new at the time trailblazer ss awd. Slammed it with coilovers and it looked good but was so low the front cv's would bind badly going around a cloverleaf anywhere near the posted speed limit. Being lowered didn't help in the winter when it slid off the road and nailed a neighbors culvert writing it off. Had it been stock height it may have had a chance of clearing it?

[Eggman]

I was a mini-truck guy. I've owned 4 Nissan D21 Hardbodys

By the way I had a 1978 Datsun extended cab for a couple of years. It had carburetor problems and lost fifth gear (probably due to a broken shift fork) but otherwise did a lot of work for me.

[Eggman]

Stop sounding like my dad! He always used to try and talk me out of buying ridiculous vehicles or doing anything to a perfectly functioning car/truck. I have slowly been starting to take some of that advice. No more trucks so high the steering column wears out from pulling yourself in by grabbing the steering wheel or cars so low you bottom out pulling out of parking lots. I do miss them all though.

I will agree, lowering probably does nothing to improve handling to it's full potential unless the shocks and coils are designed, adjusted and valved for that car. But I'd assume stiffer suspension on these cars would reduce body roll some, making it feel better?

I personally would lower mine just cause they look good lowered knowing it'd probably ride like crap now. I do plan to buy a daox bar in the future but really haven't felt a need for one. I figure/hope the longer I wait the more I'll appreciate how much a sway bar helps when I do get one. Likely next year? I'd happily be a shill if given one

Because I get the impression that the reason for lowering is Because Race Car Just Gotta Have It. I don't always follow the logic and wonder if there is any logic or if it's just a want or desire to not drive a dorky econobox.

[Fummins]

it's just a want or desire to not drive a dorky econobox.

This^

I am the poorest welfare receiving looking person where I pick my kids up from the ridiculously priced and hard to get into "day camp"(daycare) that recently re opened for the summer. But it is fun watching people struggling, and curbing thousands of dollhair in rims each week trying to park their infiniti and lexus suv's lmfao. My kids were talking about how their friends parents drive a fancy car....well ours is paid for kids and dad likes camping and beer so I'd rather spend money on that than on a $70,000 over-sized stroller with an engine. But that's something poor people would say lol.

I'd like to buy an old, loud, oil leaking, smokey,rusty farm truck to roll up with and see how many snotty stuck up looks I get, especially at home! Note to self: build ugly 4 door sleeper.

[Eggman]

I /we get lots of credibility when driving the CJ-7. My daughters friends (and even schoolmates she doesn't know) think it is the coolest thing going. I guess with that on my side I've got nothing to prove with my Mirage.

[Basic]

Because I get the impression that the reason for lowering is Because Race Car Just Gotta Have It. I don't always follow the logic and wonder if there is any logic or if it's just a want or desire to not drive a dorky econobox.

Your thread title doesn't say anything about lowering the car. It says "why change your suspension" and I will again state that I want to change mine because it is a wallowy borderline dangerous undersprung underdamped car, at least for the 14-15. I have yet to drive the improved spec.

All that said, I simply want a slightly stiffer spring rate and quality dampers along the line of a Koni Yellow or a Bilstein.

[Eggman]

Your thread title doesn't say anything about lowering the car. It says "why change your suspension" and I will again state that I want to change mine because it is a wallowy borderline dangerous undersprung underdamped car, at least for the 14-15. I have yet to drive the improved spec.

All that said, I simply want a slightly stiffer spring rate and quality dampers along the line of a Koni Yellow or a Bilstein.

I hear ya. While I haven't personally experienced the violent crashing off the bumpstops that you've described, I can see how someone would want to firm up the suspension. It's not changing the ride height, so it keeps the geometry as designed.

Too bad there aren't a whole lot of choices out there. That's why I experimented with some different springs from a junkyard - I was hoping to find something that I would consider a cheap, readily available improvement.