Suspension upgrade for non-ST (sedan)

[Dave88LX]

I had a GTI previously and loved the driving/handling of that car. Obviously I don't expect this car to drive or handle like that.

I currently have a Camaro 2SS 1LE, and this Fiesta Sedan (5-spd), approx 80K miles.

I've been daily driving the Camaro 150 miles/day (work is 75 miles away), because I hate the way this Fiesta rides and handles so much. I've put almost 25,000 miles on the Camaro since August!

I would like to get this Fiesta riding better and making it more fun to drive, as much as a little Fiesta sedan can. Not trying to sell and get an ST or anything, just roll with what I have.

Highway speeds feels "twitchy" with what seems like a good amount of body roll. Feels like any sort of highway speed maneuver will result in the thing rolling over.

Not looking to AutoX the car or anything, it's my DD, but would love to make it feel more planted and less tiring to drive. Happy with the ride of a GTI and Camaro, so as far as measuring what "stiffness" I'm OK with, there is a data point for that.

I took the Kelly A/S tires off (hate these tires) and put Winters on my steel wheels.

I just acquired a set of Konig Heliograms with 205/45-16 Yokohama Advan Fleva tires to put on. Hopefully that helps some.

I've been reading a ton of threads, but get a bit confused since I know the majority on this group have ST cars, so I don't know how the drop etc. would apply to me.

I've kind of come to the conclusion that maybe Bilstein B6 with Swift Spec-R springs might be a good ride, but there's a lot of options. I wouldn't mind losing a little bit of my wheel gap but not looking to slam/scrape it either. Looking for a "set it and forget it" setup, not dealing with adjustables or coilovers etc.

Unsure if I'd be looking at B6 or B8...there is a lot of debate on here as it relates to ST, but not sure about non-ST since I imagine those springs would be lower than my factory springs?

Hoping someone of you can chime in with what you might know. Thanks!

 

[Dialcaliper]

The Swifts are borderline drop, and will work with either B6, B8 or stock ST shocks.

According to the service manual, the base Fiesta (both Sedan and Hatch) is 0.25” higher in front, and 0.9” higher in the rear vs the ST, but for both versions there’s a +/- 0.5” allowance on the ride height.

Effectively you can add those to any measurements for the ST. Also, you’ll see a little more in the rear for the sedans extra weight. If it sits a little low, you can raise the rear 1/2” with the Powerflex polyurethane spring pads. Your front might not sit quite as low as the ST has a bit more junk in the engine bay with the turbo system.

If you don’t want quite that much lowering, I recently discovered that a certain combination of generic coilover springs 3.0” ID front and 2.5” or 60mm ID rear , both 10” free length will produce a higher spring rate (similar to the Swifts) at around stock ST ride height.

https://www.fiestastforum.com/threads/custom-rally-springs-for-stock-b6-suspension.30829/

 

[WannabeST]

I'm running a base model fiesta too. My suspension is stock, but my current plans are swift spec r springs and a rear sway bar. I just order some stickier tires for the stock wheels but I will be upgrading them by end of year.

 

[Dave88LX]

After putting these on, I definitely wouldn't mind a little bit of drop, something reasonable.

Sounds to me if I got the Swift Spec-R, the car would be sitting about where it is right now? I have a 3.5" gap up front.

 

[WannabeST]

I'm guessing here, but I think you would see around a 1-1.5" drop with swift springs. Just putting ST springs on a base model should lower a base model around 1" so I'm pretty sure the swift springs should be 1.5". If you're ok with waiting I will most likely be doing those in about 1-2 months after driving on the stickier tires. I think It'll be hard to beat handling of the swift springs for the price range, but if you just want to lower it. I think there are better options.

 

[Dave88LX]

Yeah I'm looking to not only lower it to reduce the gap, but I'm going for in improvement in handling and ride quality as well.

It's a little confusing sometimes here when I read "XYZ didn't lower my car at all", but I need to keep in mind that an ST is already a bit lower than the non-ST.

 

[WannabeST]

You also need to keep in mind everyone's build is different. different shocks, different weight, different wheel and tires combinations will all play a role in how much lower the vehicle actually goes down

 

[the duke]

Stock ST springs with a quality damper. swifts for slightly higher rates.

mod go nuts and grab a set of MOTONs.

Don’t forget changing wheel size will also reduce gap by enlarging the radius from the hub.

 

[Dave88LX]

I've read things like "The B6s are designed for oem springs. If you are using lowering springs you might want to use the B8. Otherwise, B6 should be fine."

How would this translate to a NON-ST car? Would the Swift springs be considered lowering spring (in my case), but not a lowering spring for an ST?

 

[kevinatfms]

B8's and Swift Spec R's and throw in a rear sway bar. Was perfect for me for years on track and around town. Went to coilovers and slightly regret not keeping it how it was.

 

[kevinatfms]

I've read things like "The B6s are designed for oem springs. If you are using lowering springs you might want to use the B8. Otherwise, B6 should be fine."

How would this translate to a NON-ST car? Would the Swift springs be considered lowering spring (in my case), but not a lowering spring for an ST?

Swift Spec R's are designed around the factory Fiesta ST dampers valving, length and shaft travel. They are linear rate and 212lbs/in front and rear which is an increase of 23% in front spring rate and 43% in rear spring rate on the ST. Not sure on % increase on the SE but you can find out using the stock SE spring rates and calculate from there.

They would be a performance lowering spring for and ST and a performance lowering spring for the SE but with slightly less drop due to the increase in spring rate and the lower weight of the SE sedan.

And yes, you can run Bilstein B6/B8's with the Swift Spec R on a regular SE. Most of my older suspension items from my ST went onto my brother in law's 2016 Fiesta ST hatchback without issue.

 

[Dave88LX]

Good info, thanks for the feedback on this setup!

So would the B6 or the B8 be appropriate in my case here? The wording of "B8 is for a lowering spring" is throwing me off...

 

[M-Sport fan]

For use with the Swift Spec R springs, it seems that either/or is the case as far as the two different Bilstein dampers go, since even Swift's 'tech' department/people are somewhat undecided as to which one is 'proper' for their spring.

 

[kevinatfms]

Good info, thanks for the feedback on this setup!

So would the B6 or the B8 be appropriate in my case here? The wording of "B8 is for a lowering spring" is throwing me off...

The only thing i have noticed is that people with the B8's complain of the loss in droop travel when unloaded due to the 5/8" shorter shaft. Although i never saw any chance of that happening when i ran them and the Swifts. Dont think you could really bottom the shock out either on compression so the shorter shaft really doesnt mean anything to stop a longer shaft being used.

From what i remember, Fusion Works Fab was in process of dynoing the B6/B8/B14 dampers and im a little fuzzy but i think the B6/B8 were the same valving and really only the length of the shaft was different(he can correct me if i am wrong). The B14 setup had a funky valving curve on the set he tested.

I used the B8's with Swift Spec R's successfully as have others. While others have used the B6's with Swift Spec R's successfully also. I dont think you can go wrong with either.

 

[M-Sport fan]

^^^Many on here have claimed that the B14's setup uses linear rate springs, whereas every time I have contacted Bilstein, without fail, they claim that they use progressive rate springs on that setup, front AND back.

IF they actually did valve those for progressive rate springs specifically, could that be the reason why they have a 'funky' valving curve on the damper dyno?

 

[Snrub]

I suspect you'd be fine with the B6s with a mild drop. The old Spec Miata package used B6s with adjustable coilovers sleeves/2.5" springs. It wasn't perfectly designed, but it was still pretty good.

I had B6s on my old Miata champcar with coilovers sleeves. I'm no shock expert, but I thought they seemed to work pretty well.

I always had sportscars prior to the FiST, including a 6th gen Camaro SS. The FiST definitely doesn't feel as graceful with say a higher speed emergency swerve and I imagine that would go double for a regular fiesta.

I like dialcaliper's idea of using racing springs with lengths/rates he chose. If you don't like what you choose you can sell springs and buy new ones.

 

[WannabeST]

Not sure if you have ordered anything or not yet. But I just ordered the spec-r springs for my SE. I plan to use them on the OEM shocks for now since my car only has 35k miles on it. I'll share my results after I install so hopefully that helps you decide. I'm also still on stock wheels but that will also change soon.

 

[Dave88LX]

Nope I haven't bought anything yet! Been too busy working and running around to kids' sports to do anything yet.

 

[Dave88LX]

Can't wait to do something though.
Had to do a highway-speed steering wheel yank the other day when someone tried to come over into my lane.
The resulting jouncing of the car put the back quarter of the side of my head right into the B-pillar. Not cool.

 

[WannabeST]

Yikes, I just got my springs last week. If weather allows I will be installing my springs this weekend.