Stiffer rear springs, stock height

[wrongwheeldrive]

In an attempt to increase oversteer and increase launch traction, I would like to install stiffer springs in the rear of my FiST.

As I routinely pull trailers, bike rack, ect I want to keep the stock ride height.

Everything I have found lowers the stance of the car an inch or so. I don't really want that.

I also want to avoid adjustable coilovers and the time/cost they require.

Know of anything?

Thanks!
-WWD

 

[KKaWing]

IIRC grassroots motorsports managed to ziptie the rear spring from the B-Spec coilovers on to the stock spring perch. You might have luck with the 2.5" (eibach)/ 60mm/65mm (standard metric coils) / 62mm (BC racing coils) universal coilover springs.

From this:

To this:

Obviously you don't want the 500lb spring from this kit but you can specify lower spring rates as they are just standard coilover springs.

 

[BRGT350]

increase oversteer with a rear roll (sway) bar or just use left foot braking. The ST is crazy tail happy from the factory, I couldn't imagine making it more. If I need more rotation, I just dial in a little left foot braking mid-corner to transfer load to the front and unload the rear. As for increasing front traction, try accelerating at the edge of traction. I found changing spring rates did little to change traction under acceleration.

 

[wrongwheeldrive]

IIRC grassroots motorsports managed to ziptie the rear spring from the B-Spec coilovers on to the stock spring perch. You might have luck with the 2.5" (eibach)/ 60mm/65mm (standard metric coils) / 62mm (BC racing coils) universal coilover springs.

From this:

To this:

Obviously you don't want the 500lb spring from this kit but you can specify lower spring rates as they are just standard coilover springs.

This is an interesting solution, so you're essentially stacking springs? I am not super stoked about zip tie but I'm sure some safely wire would help with longevity.

increase oversteer with a rear roll (sway) bar or just use left foot braking. The ST is crazy tail happy from the factory, I couldn't imagine making it more. If I need more rotation, I just dial in a little left foot braking mid-corner to transfer load to the front and unload the rear. As for increasing front traction, try accelerating at the edge of traction. I found changing spring rates did little to change traction under acceleration.

I am at ~35K miles. The car used to oversteer much more than it does now. I can still get it to move the rear out but it takes harsher inputs than it used to. Perhaps the stock suspension is wearing out? I can feel the rear squat more on acceleration than it used to.

I think I will start by adding a pierce rear torsion bar and see how that affects the rear end movement. I could probably order stock height springs with a higher spring rate from one of the many suspension companies, I will just have to find measurements for the stock springs.


Good suggestions. Keep em coming!!

 

[KKaWing]

They didn't reuse the tender spring (the black one). The purpose of that is to keep tension on main spring (red) when the damper is fully extended, so it doesn't bounce around loose.

 

[BRGT350]

This is an interesting solution, so you're essentially stacking springs? I am not super stoked about zip tie but I'm sure some safely wire would help with longevity.



I am at ~35K miles. The car used to oversteer much more than it does now. I can still get it to move the rear out but it takes harsher inputs than it used to. Perhaps the stock suspension is wearing out? I can feel the rear squat more on acceleration than it used to.

I think I will start by adding a pierce rear torsion bar and see how that affects the rear end movement. I could probably order stock height springs with a higher spring rate from one of the many suspension companies, I will just have to find measurements for the stock springs.


Good suggestions. Keep em coming!!

Possible bushings are wearing out. I doubt the shocks are going with the mileage. Actually, installing urethane bushings would make a difference without changing ride height. The stiffer bushings would have less compliance. The Rally America Fiestas use solid steel Heim Joints instead of bushings on the rear beam. I assume the front too, but didn't get a good look at them. You can always add more rear tire pressure and lower the front. More front traction with less air pressure and less rear traction with higher air pressure. Air pressure in the tires acts like a spring between the wheel and road. Increasing air pressure will up the wheel rate.

 

[wrongwheeldrive]

Possible bushings are wearing out. I doubt the shocks are going with the mileage. Actually, installing urethane bushings would make a difference without changing ride height. The stiffer bushings would have less compliance. The Rally America Fiestas use solid steel Heim Joints instead of bushings on the rear beam. I assume the front too, but didn't get a good look at them. You can always add more rear tire pressure and lower the front. More front traction with less air pressure and less rear traction with higher air pressure. Air pressure in the tires acts like a spring between the wheel and road. Increasing air pressure will up the wheel rate.

Hmm. Urethane bushings, that's a relatively inexpensive upgrade. I'll do some research, thanks [MENTION=1313]BRGT350[/MENTION] !

 

[BRGT350]

Hmm. Urethane bushings, that's a relatively inexpensive upgrade. I'll do some research, thanks [MENTION=1313]BRGT350[/MENTION] !

No problem. I think there are vendors in the UK that sell them if you can't find them here. There is also reports that the 2014 NA and EU bushings are the same and stiffer than the 2015 bushings. I have never been able to confirm that rumor, nor have I ever felt a difference between the 2014 and 2015 cars. If you are going through the effort of swapping bushings, I would go with urethane.