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School me on FiST sway bars...

M-Sport fan

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#21
The Mazda 2 uses the torsion beam of the stock Fiesta. Mounting holes are slightly different.
The newest Mazda 2 with rear discs (mounted inboard) may be a modified ST torsion bar - Mazda has not been able to confirm
Just how 'inboard' can their brakes be, given a beam rear suspension with stub axles??!! [???:)]
 


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Alexandria
#22
I haven't autocrossed my FiST yet but I will say that as far as handling feel, the pierce rear torsion bar is the best thing I have done for my handling. Took out all the 3 wheeling (from what I can feel), made the car much more flat around the corners, and it has allowed me to take corners much faster than before with more control. It actually has less rear rotation but more grip.
 


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Bangkok
#23
Just how 'inboard' can their brakes be, given a beam rear suspension with stub axles??!! [???:)]
You're right - I've used the wrong terminology. I meant the callipers are on the "inner" side of the wheel I.e. Towards the front of the car, rather than the back of the car like the ST
 


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Location
Bangkok
#24
Just how 'inboard' can their brakes be, given a beam rear suspension with stub axles??!! [???:)]
You're right - I've used the wrong terminology. I meant the callipers are on the "inner" side of the rotor i.e. Towards the front of the car, rather than the back of the car like the ST
 


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Location
Seattle
#25
The Mazda 2 uses the torsion beam of the stock Fiesta. Mounting holes are slightly different.
The newest Mazda 2 with rear discs (mounted inboard) may be a modified ST torsion bar - Mazda has not been able to confirm
I stand corrected! In any case, the Mazda2 aftermarket is almost non-existent.
 


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Victoria, BC
#27
I just picked up a 2015 FiST and have a long history autox'ing as well. But with a 02 WRX. The Subaru's suffer from understeer at times and a lot of serious cars will have a huge front bar to keep the front suspension planted and also keeping it from losing camber under compression. When pushed very hard the car will understeer but driven within limits you will have a increase in overall grip. I am curious if this is similar with the FiST? Does anyone know to chime in?
 


BRGT350

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Grand Haven
#28
bigger front bar=more understeer

You need to soften the front for grip and stiffen the rear for more oversteer. I have found the ST to be a little on the tail happy side with the ESC set to full off and using left foot braking. I always suggest doing the sway bar last as it is just a tuning aid. Get your tires, springs, and dampers right first. Fine tune the car with air pressure and sway bars. I used to start with sway bars since they were cheap, but years of building cars and being a suspension engineer for some time had taught me otherwise.
 


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Victoria, BC
#29
In general I agree, but specific cars and suspension designs put this into debate. Look up the FR sway info in here as it explains much better than I can. https://forums.nasioc.com/forums/showthread.php?t=1152714

Of note, I have tried 3 different sizes of sways on the front of my WRX and I can say that, even in the wet the car understeers less quickly and I had more overall grip with the larger front bar. That said, I take your advice of tweaking tires, pressures, and general setup more into account here and agree sways are the last piece. I may try the Koni yellows in the RR and switch tires once I have one or two events stock as a baseline.

Thanks for the quick reply!
 


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Seattle
#30
On the Fiesta, a larger front bar does not equal more understeer. From experience, I can tell you the car rotates better with a larger front bar, and the link provided backs it up.
The consensus Fiesta setup is either an SE or Eibach front bar and Koni rear shocks set at basically full stiff.
 


BRGT350

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#31
however, you are adding a larger front bar with much stiffer rear shocks. What happens with a completely stock suspension and a larger front sway bar?
 




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