[Mmusikanth]

Hi all,

I just threw some H&R sport springs into my 2018 f32 430i, let it settle and had it aligned.

I've noticed that when driving at high speeds mostly on the highway that when I hit small bumps, going over bridges, road markers, small potholes, that the car will jerk and sway all squirrelly like. I don't recall if the behavior was present before the alignment or not, if it was, I didn't notice it as much.

I'm worried that something might be loose, or blown... the springs have been in the car for roughly 10 days now. I noticed immediately after the alignment which was exactly 7 days after the install.

Additionally I threw on some 15mm spacers to get a pseudo-staggered setup.

Looking to the forums for some insight. Let me know what y'all think.

[SilkySmoooth]

You put on spacers at the same time? If so, take those off and report back.

[exE36M3]

Can you post your alignment numbers and where you got it done?
A bad alignment can REALLY do a number on how the car handles.

[Mmusikanth]

Originally Posted by SilkySmoooth

You put on spacers at the same time? If so, take those off and report back.

I do have spacers on,

15mm BMS spacers in the back, was hoping to match them up front with 10mm ones soon.

I'll take them off this weekend and see what happens...

[Mmusikanth]

Originally Posted by exE36M3

Can you post your alignment numbers and where you got it done?
A bad alignment can REALLY do a number on how the car handles.

I took it to a shop around the corner that outsourced their alignment... not entirely sure where it went. But here are the numbers before and after of course.

[DreamerJoe]

it is possible something wasn't tightened correctly or forgot, a lot of shops have 1 knowledgeable guy that knows his stuff and then a bunch of people that don't and just turning wrenches.. also, sometimes "shit happens" and they may have forgot, like one time a shop dropped my previous car off a lift and didn't think I would notice a huge bulge coming from under my floorboard... take it back and let them know in detail what the car is doing. you can also check it out yourself, but you already paid for the service that may not have been done correctly, and they have a lift so it shouldn't take long.

[KRS_SN]

perhaps your dampers are shot and the stiffer springs are revealing that fact now.

[exE36M3]

Yeah, I was going to say I am leaning toward what KRS_SN is saying too. The alignment numbers look ok, I look for toe and caster. When off, caster makes car drift a little on the freeway (assuming the road is perfectly flat) and toe gives you that unstable, disconnected feel (I am OVER generalizing that).

But the physical bobbing or swaying - with a lowered center of gravity, tells me to look at the shocks next.

When my BRZ passenger shock was leaking, I got some weird higher speed turning issues, mainly slow to fast compression into sharp or sweeper-like turns. That was with a stock suspension everything and at 2 years, <20k miles. I didn't "notice" as I chalked it up to skinny tires, narrow wheels and stock ride height and my aggressive driving behavior. Well when I was having springs swapped in, the shop noticed my shock was leaking fluid. A LOT of fluid. Once replaced and lowered with new sport springs (Hotchkiss), the BRZ easily was outhandling my E36 M3.

How many miles are one your car?

[Mmusikanth]

Originally Posted by exE36M3

Yeah, I was going to say I am leaning toward what KRS_SN is saying too. The alignment numbers look ok, I look for toe and caster. When off, caster makes car drift a little on the freeway (assuming the road is perfectly flat) and toe gives you that unstable, disconnected feel (I am OVER generalizing that).

But the physical bobbing or swaying - with a lowered center of gravity, tells me to look at the shocks next.

When my BRZ passenger shock was leaking, I got some weird higher speed turning issues, mainly slow to fast compression into sharp or sweeper-like turns. That was with a stock suspension everything and at 2 years, <20k miles. I didn't "notice" as I chalked it up to skinny tires, narrow wheels and stock ride height and my aggressive driving behavior. Well when I was having springs swapped in, the shop noticed my shock was leaking fluid. A LOT of fluid. Once replaced and lowered with new sport springs (Hotchkiss), the BRZ easily was outhandling my E36 M3.

How many miles are one your car?

Ugh don't tell me that the shocks are bad...

30k miles

I was hoping by going with the sport springs and not the super sports that I would be able to keep the oem shocks.

Side note, when I installed the springs I didn't notice anything overtly wrong with the shocks...

[jimbobiggens]

That sounds like bumpsteer. Lowering the car can make the lower suspension and the steering arms have different angles relative to each other. As long as the car is stationary (as in on an alignment rack) everything is fine. But go over a bump, the angles change and unwanted things happen.

https://en.wikipedia.org/wiki/Bump_steer

[KRS_SN]

Originally Posted by Mmusikanth

Ugh don't tell me that the shocks are bad...

30k miles

I was hoping by going with the sport springs and not the super sports that I would be able to keep the oem shocks.

Side note, when I installed the springs I didn't notice anything overtly wrong with the shocks...

your car is oversprung and underdamped ie unbalanced. Throw in some sports dampers or go back to oem springs

[exE36M3]

KRS_SN - as soon as you brought this up, I have to say, I agree, this is probably more likely than a blown shock.

Just looked up the HR Sport spring specs...

4-Series without Sport Suspension Package: Front Lowering: 1.5in; Rear Lowering: 1.2in
4-Series with Sport Suspension Package: Front Lowering: 1.0in; Rear Lowering: 0.75in

Hey OP - if you are in scenario 1 - lower by over an inch... and you did not replace your shocks, then the stock shocks can't handle the new springs. If I recall suspension school right... most stock shocks/springs are designed to work with (for example) 8-inches of total movement (up or down).
But let's say you drop in shorter set-of springs which only allows 4-inches of movement... but the shock was designed for 8.
So what happens? A LOT of bobbing and swaying.

Here's a video... see 3:15 min.

[Mmusikanth]

Originally Posted by exE36M3

KRS_SN - as soon as you brought this up, I have to say, I agree, this is probably more likely than a blown shock.

Just looked up the HR Sport spring specs...

4-Series without Sport Suspension Package: Front Lowering: 1.5in; Rear Lowering: 1.2in
4-Series with Sport Suspension Package: Front Lowering: 1.0in; Rear Lowering: 0.75in

Hey OP - if you are in scenario 1 - lower by over an inch... and you did not replace your shocks, then the stock shocks can't handle the new springs. If I recall suspension school right... most stock shocks/springs are designed to work with (for example) 8-inches of total movement (up or down).
But let's say you drop in shorter set-of springs which only allows 4-inches of movement... but the shock was designed for 8.
So what happens? A LOT of bobbing and swaying.

Here's a video... see 3:15 min.

Wonderful.

Thanks for the insight though!

I am in that second category, so I didn't have that much of a drop comparatively. The reason why I chose the sports instead of the super sports is that I could bring the car down without going to far out of the OEM shocks abilities. I had read enough to convince me so because I have the adaptive Sport suspension as my car is a sportline post 2016 (which is when it came standard I believe) but I guess the shocks were just not up to it.

That being said, since the back hadn't been lowered as much as the front what is the stance of just replacing the front shocks?

Either way I'll have to drive like this for now until I can afford the new shocks and install.

Anyone got shocks for sale..?

[FaRKle!]

Are you riding on your bump stops now?

[Mmusikanth]

Originally Posted by FaRKle!

Are you riding on your bump stops now?

I'm not,

The suspension handles fine when I go through bumps and such, straight on. You can feel that there is plenty enough travel that way.

It's just when I hit a bump from the side, changing lanes of whatnot that I feel a sway from side to side as the car settles back in. It's not major as in my car will lose control but it does give me some feedback.

But to answer your question, no, I'm not bottoming out

[FaRKle!]

Originally Posted by Mmusikanth

I'm not,

The suspension handles fine when I go through bumps and such, straight on. You can feel that there is plenty enough travel that way.

It's just when I hit a bump from the side, changing lanes of whatnot that I feel a sway from side to side as the car settles back in. It's not major as in my car will lose control but it does give me some feedback.

But to answer your question, no, I'm not bottoming out

There's a difference between bottoming out and riding on the bump stops. BMW's at stock height don't have much clearance to the bump stops (0.5-1.25"), so if you lower... well now you have sooner bump stop engagement, or are already riding them and boosting your spring rate and increasing forces transmitted from bumps that can upset the ride.