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Lets talk Spring Load, Not the usual Spring Rate thread

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Fusion Works

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Thread Starter #41
As far as I am concerned, most of the lowering springs are softer than stock spring rates. Swift being an exception to that rule, (however until I test them I won't say that with certainty). As proven by my debacle with the Suspension Techniques lowering springs and their BS about the rate compared to what I actually measured, I don't think the Spring companies actually do any real testing on their products.

I think the ST springs were 1in shorter than the OE Fiesta ST springs. Combine that with the 1in shorter B8 damper and they are stupid low. in my opinion. You can see the difference between the ST spring on the B8 and OE spring on the B8.

The other issue I had, there wasn't enough preload on the lowering spring to get the car far enough away from the bump stops. When I was driving the ST lowering spring on the B8s, there may have been 1in of free travel until the bumpstop touched the damper. This was at static ride height.

The B8 will affect droop travel, you will lose an inch.
 


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#42
As far as I am concerned, most of the lowering springs are softer than stock spring rates. Swift being an exception to that rule, (however until I test them I won't say that with certainty). As proven by my debacle with the Suspension Techniques lowering springs and their BS about the rate compared to what I actually measured, I don't think the Spring companies actually do any real testing on their products.

I think the ST springs were 1in shorter than the OE Fiesta ST springs. Combine that with the 1in shorter B8 damper and they are stupid low. in my opinion. You can see the difference between the ST spring on the B8 and OE spring on the B8.

The other issue I had, there wasn't enough preload on the lowering spring to get the car far enough away from the bump stops. When I was driving the ST lowering spring on the B8s, there may have been 1in of free travel until the bumpstop touched the damper. This was at static ride height.

The B8 will affect droop travel, you will lose an inch.
From what I understand, the Eibach springs are supposed to be about 5% stiffer than the original springs, but what they measure is another story like you said! They do feel stiff though with very little body roll in the corners.

So from what you’re saying then, the original springs with the B8’s would be a better option than the Eibachs with a spacer until I can get some Reigers?

The B8’s that I have are slightly different to standard ones as they were made for M-Sport to go on as a handling upgrade for the M-Sport edition cars so I’m not sure of valving etc.
 


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#44
In my email with Bilstein, they recommended B6s with OEM ST springs.
Yes, I think it’s the B6 struts that are recommended with standard springs. Although with the ST springs being slightly lower than standard fiesta springs I was wandering if the original ST springs would still work well with the B8 struts seeing as there’s hardly any preload when using lowered springs.
 


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#45
From what I understand, the Eibach springs are supposed to be about 5% stiffer than the original springs, but what they measure is another story like you said! They do feel stiff though with very little body roll in the corners.

So from what you’re saying then, the original springs with the B8’s would be a better option than the Eibachs with a spacer until I can get some Reigers?

The B8’s that I have are slightly different to standard ones as they were made for M-Sport to go on as a handling upgrade for the M-Sport edition cars so I’m not sure of valving etc.
I still do not know why M-Sport did not just put the old R1 class, not rebound or damping adjustable, Bilstein Motorsport spec coil over conversion fronts, and Motorsport with weight jacker/height adjuster on the spring rear on those cars instead of the plain old B8s. [dunno]

I'm guessing that they thought it would be way too harsh on bad roads, especially in tarmac spec (besides having to add about $3K USD to that special edition's price)?
 


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#46
I still do not know why M-Sport did not just put the old R1 class, not rebound or damping adjustable, Bilstein Motorsport spec coil over conversion fronts, and Motorsport with weight jacker/height adjuster on the spring rear on those cars instead of the plain old B8s. [dunno]

I'm guessing that they thought it would be way too harsh on bad roads, especially in tarmac spec (besides having to add about $3K USD to that special edition's price)?
That would have really made the car stand out! I believe it would have come down to costs and the fact that many prefer the ‘lowered’ look :rolleyes:
 


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Thread Starter #47
In my email with Bilstein, they recommended B6s with OEM ST springs.
Lets not rely on the clown answering the phone at Bilstein in CA for anything beyond, "bolt our parts on as we recommend". If you ask the guy about spring preload his head would explode.
 


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Thread Starter #48
From what I understand, the Eibach springs are supposed to be about 5% stiffer than the original springs, but what they measure is another story like you said! They do feel stiff though with very little body roll in the corners.

So from what you’re saying then, the original springs with the B8’s would be a better option than the Eibachs with a spacer until I can get some Reigers?

The B8’s that I have are slightly different to standard ones as they were made for M-Sport to go on as a handling upgrade for the M-Sport edition cars so I’m not sure of valving etc.
5% is in the noise from a feel stand point for a street car. Is that 5% of the Fiesta ST rate or the Fiesta base rate?

I would run the B8 with a stock spring if you have them, if not then a 15mm spacer with the B8 is probably a solid option. What were the Msport Bilsteins you have designed to do? Work with a stock spring or a lowering spring or both?
 


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#49
Lets not rely on the clown answering the phone at Bilstein in CA for anything beyond, "bolt our parts on as we recommend". If you ask the guy about spring preload his head would explode.
Albeit much more tech savvy than the 'techs' (or clowns) answering the phones at Bilstein USA, the people I've spoken to at Swift could not give a definitive answer about which Bilstein damper to use with their Spec R springs for our cars.

He kept hemming and hawing/waffling back and forth between the two.

I guess the only way to get it correct is to measure everything, and then use the one with the closest travel to the Spec R, and then re-valve it precisely for that spring's rate, with the correct bumpstops?? [dunno]
 


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#50
5% is in the noise from a feel stand point for a street car. Is that 5% of the Fiesta ST rate or the Fiesta base rate?

I would run the B8 with a stock spring if you have them, if not then a 15mm spacer with the B8 is probably a solid option. What were the Msport Bilsteins you have designed to do? Work with a stock spring or a lowering spring or both?
5% is in the noise from a feel stand point for a street car. Is that 5% of the Fiesta ST rate or the Fiesta base rate?

I would run the B8 with a stock spring if you have them, if not then a 15mm spacer with the B8 is probably a solid option. What were the Msport Bilsteins you have designed to do? Work with a stock spring or a lowering spring or both?
They’re supposed to be 5% stiffer front and back than the original ST ‘13-‘15 springs. There are also Eibach redlines available which are lower and softer than standard springs.

This is what I got back when I contacted M-Sport directly about the struts -
“The M-Sport dampers came to market before Bilsteins generic parts, so I'm not sure what the actual differences with the valving are. If I remember correctly Bilstein set up 2 sets of prototypes with different valving and at M-Sport Malcolm drove 001 back to back with the different sets and chose the one he preffered. M-Sport's chief development driver Dave Linday also drove the car back to back too. I believe the other set was then what Bilstein went with.”
The car was driven around the m-sport testing circuit and Malcolm Wilson was happy with the way it handled and signed it off.

The springs that originally came with the handling pack was the Eibach pro-kit. The car is pin sharp when driving, and you can feel every contour and bump of the road beneath you, but the front definitely looks too low by about half an inch or so, therefore the spacer would be a good option I feel and might add a bit more pre-load which would help with nose dive when braking.

Another option that I’ve seen is a company in the UK caked AVO are selling rally suspension for the fiesta ST180. They do a R1 set which is one way adjustable for bump/rebound combined and a R2 set which has independent bump and rebound setting. I’m unsure of the spring rates and damping and haven’t seen any reviews. These might be a good option for anyone who would like more travel and a stiff, strong shock but can’t get hold or afford the reigers.
 


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#51
Albeit much more tech savvy than the 'techs' (or clowns) answering the phones at Bilstein USA, the people I've spoken to at Swift could not give a definitive answer about which Bilstein damper to use with their Spec R springs for our cars.

He kept hemming and hawing/waffling back and forth between the two.

I guess the only way to get it correct is to measure everything, and then use the one with the closest travel to the Spec R, and then re-valve it precisely for that spring's rate, with the correct bumpstops?? [dunno]
Yes, it’s surprising how many miss matched struts/spring combo are out there! It does say on Swift springs website that the springs are made to match the original struts valving. How true this is I’m not too sure!
 


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#52
Yes, it’s surprising how many miss matched struts/spring combo are out there! It does say on Swift springs website that the springs are made to match the original struts valving. How true this is I’m not too sure!
Yes, and also given that those who have installed the Spec Rs usually have seen minimal lowering overall, I'm guessing that the B6es would work just fine with those springs which use that built-in tender/'helper' spring type section. [wink]
 


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#53
They’re supposed to be 5% stiffer front and back than the original ST ‘13-‘15 springs. There are also Eibach redlines available which are lower and softer than standard springs.

This is what I got back when I contacted M-Sport directly about the struts -
“The M-Sport dampers came to market before Bilsteins generic parts, so I'm not sure what the actual differences with the valving are. If I remember correctly Bilstein set up 2 sets of prototypes with different valving and at M-Sport Malcolm drove 001 back to back with the different sets and chose the one he preffered. M-Sport's chief development driver Dave Linday also drove the car back to back too. I believe the other set was then what Bilstein went with.”
The car was driven around the m-sport testing circuit and Malcolm Wilson was happy with the way it handled and signed it off.


The springs that originally came with the handling pack was the Eibach pro-kit. The car is pin sharp when driving, and you can feel every contour and bump of the road beneath you, but the front definitely looks too low by about half an inch or so, therefore the spacer would be a good option I feel and might add a bit more pre-load which would help with nose dive when braking.

Another option that I’ve seen is a company in the UK caked AVO are selling rally suspension for the fiesta ST180. They do a R1 set which is one way adjustable for bump/rebound combined and a R2 set which has independent bump and rebound setting. I’m unsure of the spring rates and damping and haven’t seen any reviews. These might be a good option for anyone who would like more travel and a stiff, strong shock but can’t get hold or afford the reigers.
Have you seen any kind of pricing on those two AVO models at all?

I have given up on ALL of the U.S. based, or available in the USA coil over setups for this car, even including the ones which proclaim that they are built for (gravel and tarmac) rallying (I NEVER get a straight answer from any of them, and they give almost NO info about their product(s) at all [mad]). [:(]
 


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Thread Starter #54
There is a 1in difference in the B6 and B8. For the most part that affects the droop levels. If you stick a 1in shorter spring on the stock length B6 you will have less spring load than with the stock spring. Having the Swift be a higher rate, might actually bring back that spring load back to level similar to the OE on the OE strut. But using that lowering spring on a B6 will generate less spring load. This is what I have seen with my car and my testing.

I ran the OE ST dampers with the Suspension Techniques lowering spring and the car was extremely low. (in my opinion, not air bag low). It was lower with that shorter spring stuck on the B8 damper, I think. Either way, the ST spring is way too soft for anything useful.

In my opinion, the big take away here from this whole conversation. You need to know your spring load. This will determine what combination of parts generate the proper loads. The smartest move seems to be to combine a shorter spring with a shorter strut to create a higher preload number, which will help get the spring load number closer to stock. Running a stock spring on a B8 damper gets you more preload and thus a higher over all spring load. That will lower the car slightly, but keep it at a reasonable ride height.
 


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Thread Starter #55
BTW I am swapping back to my "summer tires" this week. I am currently running a 204/45-17 and going back to a 205/40-17 RT660. I feel like this current setup is not as tied down as my custom valved set, but is not tossing the car around in large bumps like my custom set is.

I have the rear dampers apart to change the bleed shim to see if I can make it a bit more compliant in the .5-2.5in/sec range.
 


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#56
BTW I am swapping back to my "summer tires" this week. I am currently running a 204/45-17 and going back to a 205/40-17 RT660. I feel like this current setup is not as tied down as my custom valved set, but is not tossing the car around in large bumps like my custom set is.

I have the rear dampers apart to change the bleed shim to see if I can make it a bit more compliant in the .5-2.5in/sec range.
It will be interesting to see where your set up ends up and what you’ll find to work best.
 


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#57
@Fusion Works So from your testing then would you say a standard pre ‘16 spring would work better on a Bilstein B8 kit than any “lowered” spring?
I’m still looking for used reigers, but in the mean time I’m looking for a set of springs that don’t lower the front of the car too much on the B8’s. So far, the options that I’m thinking of is fitting a 15mm spacer onto my current Eibach springs which sit 25mm lower than standard. This might add a bit of pre-load to the spring and stiffen the front spring slightly and possibly help with the roll centre? Or, I could change the Eibachs for the pre ‘16 original springs. Which one of these options would you recommend and would either effect front suspension droop and handling?
I need some travel as the roads where I live are quite bumpy and uneven with broken tarmac sections. At the moment there is about 15mm gap between the front tyres and the arch. Is this too low? Thanks! (y)
hey, few things I want to add:

Roll centre adjustment is RLY complicated. It will influence a lot of things, including dynamic change of toe, camber and your % of ackermann steering. Understanding what it rly is and measuring it can take time. Simply putting stiffer springs or spacers to your front suspension will not rly work wonders, it can even make some things worse. The roll center advice and adjusters you can buy on some "tuning" websites are 75% garbage. This is a good blog read if you are not scared of formulas: Rodrigo Santos - a discussion on steady state lateral weight transfer and how to use it in setup

If you rly want to do this yourself, you need to do the following steps, some of them are complicated and youll need to do research and testing:

1.) Measure your suspension and calculate roll centre for rear AND front suspension.
2.) Measure and calculate CG of your car
3.) Calculate or simulate static load transfer of your car
4.) test and measure your car on the track (this can be complex and Sensors can be expensive to borrow)
5.) do adjustments, go back to step 3

this can be a time consuming and expensive process, also you need to get the tools and learn the math/physics behind it. Load transfer is NOT easily understood by roll centre height. Body roll is NOT easily related to load transfer. Handling is a lot more than those two topics. Increasig roll inertia or roll stiffness on one end of the car changes load transfer to/on the other side, so you rly need to have a good understanding what you are changing.

My advice: try stiffer (not shorter) springs front and rear with your b8, see if the reduced body roll feels better. If yes, have a good time driving it on the streets ✌️

Reigers are expensive and for rally, they are durable and have great valving and damping, but for everyday street use in a non seam welded car with no cage it is maybe not the right thing. If you want to get into some rough road/gravel driving you also need to adapt and reinforce your suspension pick up points with at least a cage. If not you will fuck up stuff in the long run.
 


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#58
Reigers are expensive and for rally, they are durable and have great valving and damping, but for everyday street use in a non seam welded car with no cage it is maybe not the right thing. If you want to get into some rough road/gravel driving you also need to adapt and reinforce your suspension pick up points with at least a cage. If not you will fuck up stuff in the long run.
TRUE, but I will add that Barry McKenna was using 3 way Reigers on his Focus RS recce (a rally 'pre-runner' type car for those not in the know) car, along with those M-Sport OZ 'disc' R2T wheels and real gravel tires), without any tied-in/triangulated cage, or chassis bracing at all, and not even a roll bar.

But then again, that most likely was NOT one of his daily driven street use cars, and I've only seen it at that one event (NEFR in 2019), so I agree with the last sentence above.
 


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#59
There is a 1in difference in the B6 and B8. For the most part that affects the droop levels. If you stick a 1in shorter spring on the stock length B6 you will have less spring load than with the stock spring. Having the Swift be a higher rate, might actually bring back that spring load back to level similar to the OE on the OE strut. But using that lowering spring on a B6 will generate less spring load. This is what I have seen with my car and my testing.

I ran the OE ST dampers with the Suspension Techniques lowering spring and the car was extremely low. (in my opinion, not air bag low). It was lower with that shorter spring stuck on the B8 damper, I think. Either way, the ST spring is way too soft for anything useful.

In my opinion, the big take away here from this whole conversation. You need to know your spring load. This will determine what combination of parts generate the proper loads. The smartest move seems to be to combine a shorter spring with a shorter strut to create a higher preload number, which will help get the spring load number closer to stock. Running a stock spring on a B8 damper gets you more preload and thus a higher over all spring load. That will lower the car slightly, but keep it at a reasonable ride height.
So, just how much static ride height would I lose pairing the Spec Rs with B8s vs. B6es, and does the resultant higher 'load' mentioned above mean that the B8 setup will not allow the unibody to come as close to the (VERY rough) gravel stage roads as the same springs on the B6es during compression? [???:)]
 


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#60
TRUE, but I will add that Barry McKenna was using 3 way Reigers on his Focus RS recce (a rally 'pre-runner' type car for those not in the know) car, along with those M-Sport OZ 'disc' R2T wheels and real gravel tires), without any tied-in/triangulated cage, or chassis bracing at all, and not even a roll bar.

But then again, that most likely was NOT one of his daily driven street use cars, and I've only seen it at that one event (NEFR in 2019), so I agree with the last sentence above.
maybe for recce it is possible :unsure: I drive with almost the fiesta "active" stock suspension setup and know many people with bilstein b6 and stock springs that drive on rallycross tracks (a lot smoother than a rally stage), but if you go flat out without care, i think your chassis will get bent in some places
 




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