Feisty the "Family Car"

[SVTBob]

Great news ! Look forward to your feedback.

 

[Dialcaliper]

Obligatory link for the dedicated “Rally Springs” topic. I also posted some extra tips for easier install.

Custom Rally Performance Springs Post

Install Tips

 

[jivenene]

Glad to hear! I will say that when I was running the B6/Rally springs, the combination of ride height and stiffer spring rates definitely helped a lot with both ground clearance and rubbing, but also paradoxically, ride quality because I wasn’t bottoming into the front and rear bumpstops literally all the time. The stock setup engages the nose of the front bump after only 1/2” of compression and the rear bump soon after. The nose of the bumpstops are soft so they act like a spring aid for the first inch or two, but it also means that they ramp shortly after that and produce uncomfortable jolts.

If you do try the rally spring setup, I’d love to hear feedback as so far I haven’t seen anyone else try it (or at least none commenting)

Thanks for all the great and consistent feedback! I have a couple more questions!
How do you think the stock 14-16 (or 17-19 even) springs would work with the B6s? Seems like you mentioned that a few times. I'm assuming the ride height would be exactly stock height?

Second, any idea if the rear shocks that come with the B14 ST kit (labeled F4-BE3-G752) are identical to the B6 or B8 fiesta st rear shocks? After an accident, the body shop installed a B6 on the side that got hit, so now the part numbers are mismatching and I don't know if the damping rates are the same...

thanks!

 

[Dialcaliper]

Thanks for all the great and consistent feedback! I have a couple more questions!
How do you think the stock 14-16 (or 17-19 even) springs would work with the B6s? Seems like you mentioned that a few times. I'm assuming the ride height would be exactly stock height?

Second, any idea if the rear shocks that come with the B14 ST kit (labeled F4-BE3-G752) are identical to the B6 or B8 fiesta st rear shocks? After an accident, the body shop installed a B6 on the side that got hit, so now the part numbers are mismatching and I don't know if the damping rates are the same...

thanks!

The B6’s were originally designed to be stock replacement (with stock springs), so they should work fine.

The B14 rears are the same shock body, but the damping is lighter than both the B6/B8 and even the stock Ford rear dampers. I believe they have a shorter shock shaft like a B8, so that will affect droop height

Unfortunately they are not the same damping at all. Your choices are probably these:
1) Install a second B6 to match and see if you like the end result or not
2) Contact Bilstein (aftermarket in So-Cal) and let them know about the accident and ask if they’ll sell you a single rear B14. You might need to send in the wrecked B14 if the shop didn’t throw it away
3) Ask Bilstein instead if they’ll either revalve your B6 or sell you a B6/B8 revalved to the B14 damping spec. However, I believe the B14 has a shorter shock shaft similar to the B8.
4) pick a still different rear damper for both rears (maybe a KYB or Koni adjustable) and match the original damping as best you can

Testing courtesy of @Fusion Works
https://www.fiestastforum.com/threads/bilstein-science-experiment.29105/#post-482235

 

[M-Sport fan]

I believe that some of the vendors will sell you a single B6 damper.

But most likely none would sell an individual B14 damper.

 

[jivenene]

I believe that some of the vendors will sell you a single B6 damper.

But most likely none would sell an individual B14 damper.

I'll give them a call tomorrow and see what they say.
Yeah it makes sense that the shocks that come with the B14 are different than the B6, since the ride height is minimum 1" lower.

I'll probably end up buying another B6 rear and then trying out stock spring since they can be gotten for free or cheap and maintain stock height.....

 

[Dialcaliper]

I'll give them a call tomorrow and see what they say.
Yeah it makes sense that the shocks that come with the B14 are different than the B6, since the ride height is minimum 1" lower.

I'll probably end up buying another B6 rear and then trying out stock spring since they can be gotten for free or cheap and maintain stock height.....

If you’re keeping the B14 springs in front, stock rear springs will be too soft to keep up, and you’ll get some uncomfortable pitching behavior regardless of the dampers you’re using. Either keep the B14 rear springs as long as they still have enough preload to stay in place, or else swap in some similar rate 2.5”ID coilover springs in the rear along with some helpers - if you keep the Bilstein adjusters, a 4k or 225lb/in 7” long spring plus helpers, or if you remove the adjusters, a 200lb/in 10” spring (like the one I spec’d for the rally spring setup) plus the helper will be stiff enough.

Unless of course you plan to swap back to stock springs and B6 struts all around

 

[Fusion Works]

I would even tell you to run the B6/B8 damper on the rear compared to the B14 rear damper.

Bilstein probably won't sell you any parts from the B14 kit. All of those kits are made in Germany and US really has little input into their design. I am trying to get the adjustable shafts from the B16s but Germany is not cooperating with me. I am not supposed to be building shocks, cuz I am a hill billy, not a pure German certified Shock specialist. US Bilstein Motorsports can't even get these parts.

 

[jivenene]

If you’re keeping the B14 springs in front, stock rear springs will be too soft to keep up, and you’ll get some uncomfortable pitching behavior regardless of the dampers you’re using. Either keep the B14 rear springs as long as they still have enough preload to stay in place, or else swap in some similar rate 2.5”ID coilover springs in the rear along with some helpers - if you keep the Bilstein adjusters, a 4k or 225lb/in 7” long spring plus helpers, or if you remove the adjusters, a 200lb/in 10” spring (like the one I spec’d for the rally spring setup) plus the helper will be stiff enough.

Unless of course you plan to swap back to stock springs and B6 struts all around

Not gonna lie, I'm not doing any gravel/dirt driving, so yeah, I'm most likely gonna end up with stock springs and B6s and call it a day!

 

[Dialcaliper]

Not gonna lie, I'm not doing any gravel/dirt driving, so yeah, I'm most likely gonna end up with stock springs and B6s and call it a day!

What year is your car? Ironically one of the reasons I ended up pursuing the “rally” springs idea is that it was remarkably difficult to locate a set of Pre-2016 springs 🤦

 

[M-Sport fan]

Not gonna lie, I'm not doing any gravel/dirt driving, so yeah, I'm most likely gonna end up with stock springs and B6s and call it a day!

Even if you were going to do some low(er) speed, gravel/dirt driving, that combo would handle it just fine, even with the post early '16 build springs.

My car with full factory suspension (LATE 2016 build, so yeah, softer spring rates) was kind of amazing at handling even the worst of the gravel stage rally roads I drove on when working/volunteering on ARA rallies.

 

[jivenene]

What year is your car? Ironically one of the reasons I ended up pursuing the “rally” springs idea is that it was remarkably difficult to locate a set of Pre-2016 springs 🤦

i have a 2018, but a local guy here in SD is selling me his 2015 springs, because he wants to tinker with your 10" rally spring idea. Win-win for all! He is a lot more interested in track driving than I, which means he has a great way to test suspension setups too! Anyway, if he finds some amazing combination of spring/damper, I might move to that in the future, but for now, I need the more compliant street setup for the sh*t streets we have here in SD.

 

[Volumetrik]

Great read as always. Why did you choose tender springs VS helper springs? In page four of this thread, you explain :

The heavy tender/assist spring is tuned to give adequate preload, and a dual-rate like behavior in droop to help with shock extension on rough back roads, but will be fully bottomed at static ride height.

Does this mean that swapping to helper springs (which have a negligible effective spring rate) in a setup like yours would :

1- Not give adequate preload
2- Not help the shock extension on rough back roads?

 

[Krackenamg]

Around November, I decided that I was tired of pushing the button to disable the rather invasive ESC every time I got in the car, and after poring over the wiring diagrams and the internet, by January I'd finally located all of the components to do a custom auto-button pusher! Since I'm running a tune and it doesn't matter as much, I configured it to turn on "Sport Mode" 30 seconds after starting the car to avoid the occupying the Sync with the progress-bar for "ESC-off"

At the same time, I took the opportunity to pull wires and correct some questionable wiring the previous owner did to install the little Kenwood Sub under the driver's seat, by installing terminals in the engine fuse box

I've done a full writeup on both.

Auto Sport Mode Module: https://www.fiestastforum.com/threads/diy-fun-mode-automatic-sport-mode-esc-off-circuit.30262/

Fusebox Guide: https://www.fiestastforum.com/threa...erminal-part-numbers-no-more-fuse-taps.30228/

great job done there..

 

[Dialcaliper]

Great read as always. Why did you choose tender springs VS helper springs? In page four of this thread, you explain :


Does this mean that swapping to helper springs (which have a negligible effective spring rate) in a setup like yours would :

1- Not give adequate preload
2- Not help the shock extension on rough back roads?

Helper springs fill function #1. Which is adequate preload to keep the springs from falling out.

#2 is where having a heavier helper spring may help. Once the weak helper is no longer fully compressed, both the spring rate and the total extension force provided by the spring can in some cases not be enough to keep the wheel in contact with the ground as you go across a dip, or come off an abrupt hump and actually catch air if only very briefly. If this happens while cornering, a wheel not on the ground is literally a wheel that can’t provide lateral force any longer.

Under extremely hard braking coming off a rise is another case where the rear wheels can lift, causing instability, zero braking contribution from the rear wheels and possibly some pucker-worthy sensations from the drivers seat.