2014 Mazda3 Shocks: Coilovers?

[MRC01]

My Mazda3 has a bad (leaking) shock, so I'm gonna replace it. While I'm at it, I was considering upgrading shocks & springs all around. I used to autocross high performance cars and still enjoy spirited driving and good handling. I've already installed a stiffer rear sway bar in this car, which improved the handling. Everything else on the car is OEM.

I'm familiar with coilovers, had a Panoz Roadster that came with them as OEM. They're great, got that car perfectly 4-corner balanced with my weight in the drivers seat. But coilovers may be overkill on a Mazda 3; maybe all it really needs is adjustable shocks and stiffer springs. Then again, perhaps coilovers will be nice even for this car. I don't want to lower it, just want to use the failed OEM shock as an excuse to upgrade the handling. Tirerack has a set of Bilsteins P14 my car for about $900.

Any advice?

 

[AutoMechanic]

Based on what I have heard I’d stick to OEM. Though I have had great luck with Monroe.

 

[slacktide_bitog]

The B14/PSS are height-adjustable only with fixed damping, which makes no sense and isn't worth it.

Just get the Bilstein HD shocks

If you want adjustable, there's the Koni yellow

 

[MRC01]

Based on what I have heard I’d stick to OEM. Though I have had great luck with Monroe.

I definitely want a stiffer suspension. Not full race stiff, but streetable autocross stiff. Are you suggesting OEM shocks with stiffer springs? If I increase the spring rates I probably want stiffer shock damping to match.

 

[AutoMechanic]

I definitely want a stiffer suspension. Not full race stiff, but streetable autocross stiff. Are you suggesting OEM shocks with stiffer springs? If I increase the spring rates I probably want stiffer shock damping to match.

Yeah you could change the springs to something else. Bilstien also makes good ones too that are pretty stiff from my experience.

 

[MRC01]

The B14/PSS are height-adjustable only with fixed damping, which makes no sense and isn't worth it.
Just get the Bilstein HD shocks
If you want adjustable, there's the Koni yellow

Ah, something like this.

 

[lizpat]

The B14/PSS are height-adjustable only with fixed damping, which makes no sense and isn't worth it.

Just get the Bilstein HD shocks

If you want adjustable, there's the Koni yellow

I am VERY strongly considering getting the Bilstein B14 for my Honda Fit 2012. Why do you think the B14 in general is a bad idea? Is it just the lack of adjustability?

 

[slacktide_bitog]

I am VERY strongly considering getting the Bilstein B14 for my Honda Fit 2012. Why do you think the B14 in general is a bad idea? Is it just the lack of adjustability?

If you adjust the height, you need to adjust the damping, too. The higher end coilovers will do this, such as Bilstein's own B16 aka PSS9 and PSS10

 

[Jetronic]

The B14/PSS are height-adjustable only with fixed damping, which makes no sense and isn't worth it.

Just get the Bilstein HD shocks

If you want adjustable, there's the Koni yellow

It makes sense if all the OP wants to do is corner weigh balance the car

 

[MRC01]

I learned a bit more...
The Eibach springs linked above aren't stiffer than stock. They are for lowering, which is not what I'm looking for. I don't mind if the car ends up a bit lower (say, less than an inch), but my goal is to stiffen the suspension, not lower the car.
Several coilovers are available, but most change the handling balance (front/rear springs not stiffened proportionally) and they make camber adjustment difficult. The rear sway bar I installed shifted the handling balance exactly how I like it (reducing understeer), so I don't need differential spring rates to achieve what I've already done, and mess it up.

I found a different solution for my goal:
First, Koni Sport adjustable shocks, same ones linked above.
Second, Racing Beat springs, which are 20% stiffer (proportionally front/rear) than OEM.
Both say they are bolt-on OEM replacements, so they should fit together, right?
This combined with the stiff rear sway bar I already installed, should get the car exactly how I want it.

 

[Pew]

Eibach Pro-Kits should be progressive. They have them listed on their tech PDF here as:

Front:
OEM: 143lbs/in
ProKit: 166-280lbs/in

Rear:
OEM: 171lbs/in
ProKit: 137-194lbs/in

You may also want to find out if you will need a roll center kit with lowering the car as well (if you do) otherwise the stiffer springs won't be of much help.

 

[MRC01]

Thanks for that tech info. Eibach hides it pretty well on their website, I couldn't find it. But it looks about right. Note that the Eibach springs lower the car more than I want, and they increase front stiffness more than rear. That tends to increase understeer, which I don't want. The car has way too much understeer from the factory and I installed a stiffer rear swaybar to fix that. Since I already got the front-rear dialed in the way I want, if I increase the spring rates I want to do it proportionally front-rear so they don't change relative to each other. And I don't want to lower it because (as you alluded) that changes a bunch of other stuff and not necessarily an improvement in performance.

 

[meep]

I’m liking your idea for Koni yellows. Is tokico still around? They made adjustables, as well as KYB.

I enjoyed a set of kyb gr2s years ago. Stiffer than stock but also understood opening up for speed bumps, resulting in a car that wouldn’t lean in a corner but could also hit potholes without cracking teeth. I didn’t have it long enough to see how they’d fare long term.

also, props for staying stock ride height. A nicely set suspension doesn’t need to lower for performance reasons unless you’re tuning to extremes, unless one just wants the look. You’ve obviously done your homework with your Mazda.
m

 

[MRC01]

... Is tokico still around? They made adjustables, as well as KYB. I enjoyed a set of kyb gr2s years ago. ... also, props for staying stock ride height. A nicely set suspension doesn’t need to lower for performance reasons ...

Years ago I used to autocross a '95 RX-7 and '00 Panoz Roadster, had both cars set nicely getting competitive times. And they were super fun to drive (street legal). I'm trying to apply what I learned back then to this Mazda 3. It's FWD which can't be fixed but I'm going for the simplest way to get handling as good as possible, consistent with being a daily driver. It's a learning experiment.

The rear swaybar (made by Progress) is better than OEM quality, has roughly twice the stock rate and made a nice improvement: less body roll, less understeer, more precise steering. But still very streetable. And it's cheap and only takes about 30 minutes to install. If you only do 1 thing to this car, that's the thing to do.

After I install the Koni shocks & RB springs, then take it to the shop to dial in the alignment, then drive and tweak it, I'll report back. The Mazda 3 is a common car so there probably are others who want to improve the handling.

 

[UG_Passat]

Koni yellow is only adjustable in rebound.

In many cars, the Koni adjustment is not using a knob for the rear, it may require removal of the shock to adjust the rebound setting. (Push the shock rod down all the way and turn)

The B14 kit, will likely use their B8 monotubes, which is more than capable of handling its lowering range (20 to 40mm)

 

[MRC01]

Koni yellow is only adjustable in rebound. In many cars, the Koni adjustment is not using a knob for the rear, it may require removal of the shock to adjust the rebound setting. (Push the shock rod down all the way and turn)

Some Koni yellows are adjustable both ways, but not the ones for my car. The front (8741) and rear (8040) adjust differently. The fronts are easy to adjust: turn a knob at the top. No need to remove or even lift the wheel. The rears are hard to adjust: remove the shock from the car, and turn it while fully compressed.

 

[DuckRyder]

B14 all the way...

 

[MRC01]

Bilstein B14 not available for my 3rd gen Mazda 3. That was according to Tire Rack. According to Bilstein, they are available. The only docs I can find on those B14s are in German. They don't seem to give details like the spring rates or how it affects the alignment.

 

[DuckRyder]

Bilstein B14 not available for my 3rd gen Mazda 3.

My bad, the coil over kit you are talking about...

Bilstein

 

[MRC01]

My bad, the coil over kit you are talking about...

https://www.tirerack.com/suspension...a3+5-Door&autoYear=2014&autoModClar=i+Touring

I saw those, and several other coilover kits for the Mazda 3. I passed over them because they don't give actual spring rates, it looks like they're intended mainly for lowering, and most of the coilover kits have a more intensive install that requires drilling out the strut tower centers and installing camber plates to adjust the alignment.

A guy at Mazda3Revolution compiled a list of various spring & coilover options, for those who are interested.

I opted for a configuration that is less invasive, more of a bolt-in OEM part swap, and popular with autocrossers who care more about lap times than appearance or ride quality.