I don't have the car handy to measure, and I want to order the bushings. Moog lists for the 86 Fiero a bushing for "13/16" and smaller bar" (K5242), as well as a bushing for a "7/8" and larger bar" (K3110).
I would have assumed the 7/8 was only the aftermarket upgrades, but found lots of conflicting info.
My original 1985 WS6 front stabilizer bar was 23 mm but I picked up another bar in the JY that is 22 mm...I believe that one came off an 86 GT.....
Amazingly, I swapped them a couple of times and never noticed any difference....(I have the 88 rear subframe/suspension on my 85...plus some odd mods to make it handle better...)
I was actually surprised that it was smaller- but without a rear bar it would make some sense if they were trying to back off the understeer a bit in later GTs.
I grabbed it because A) I wanted to test if it would change my handling (Not much if any) and also, B) My "Crazy stabilizer bar mounting theories" put the arms at an angle so the rubber end-link bushings were not happy- I had my race shop buddy cut the ends on one of the bars and weld them on at a angle.....
Are all bars being mentioned solid? Or all tubular? A 20mm solid bar would be ~roughly~ equivalent to a 23mm tubular, but the solid bar would be heavier in relation to its stiffness.
I just bought the last set of ADDCO bars that The Fiero Store had, for my '88 GT. I recall seeing that the front was something over an inch and the rear was an inch, or so, but now I'm wondering what I bought and how they compare to stock. 28mm front and 22mm rear are pretty beefy. They're mounted pretty far out on the control arms, so their motion ratio isn't even bad.
Does anyone know if the stock bars are hollow/tubular or solid? If the stock bars are hollow and these ADDCO bars are just the same size, but solid, I'm gonna be a little peeved. I bought them as a knee jerk reaction and didn't investigate as I should have.
All the Fiero bars are solid.....The rear 88 bar is One-to-one ratio, as it is attached to the strut/spindle directly. The front bar appears to be around 90%.
I did some odd things to my stabilizer bar mounting to get better turn-in and less DTO....Most mid-engine cars are not very "Tossable" but mine is; Turn-in is almost telepathic and yet DTO is so mild that it almost doesn't exist...
All the Fiero bars are solid.....The rear 88 bar is One-to-one ratio, as it is attached to the strut/spindle directly. The front bar appears to be around 90%.
I did some odd things to my stabilizer bar mounting to get better turn-in and less DTO....Most mid-engine cars are not very "Tossable" but mine is; Turn-in is almost telepathic and yet DTO is so mild that it almost doesn't exist...
That was a good read and good experimentation on your part. I believe the result of your experiment could be attributed to having dialed in more understeer via lateral load transfer bias (reducing DTO), but improved turn-in with that much stiffer front bar. Props for coming up with a way to fine tune your bars since you don't have adjustable bars with various holes to easily affect the overall stiffness and resulting lateral load transfer bias.
I've been through this type of tuning on OEM work (I was the vehicle dynamics performance engineer on the Charger/Challenger/300 a couple years ago). For example, in a package I was tuning for the Challenger R/T, reducing the front bar stiffness resulted in a slower initial steering response, but reduced understeer once the weight transferred.
In the case of bushings, they're effectively only changing the response of the bar to the input. Not so much outright rate. There was some discussion on rubber bushings adding rate and "bonded" bushings are used in some OEM applications to add rate to the bar without adding mass. In non-bonded bushings, like ours, they would only affect response and compliance.
Also note that in pure pitch and dive scenarios, the bars are not in the picture at all because both sides move together. They do not add any spring rate. I'm not sure if that was fully understood or not from the post.
How would you factor in Rodney Dickmans zero-lash sway bar end links? I installed them and the handling felt more responsive in turns, with lighter steering feel. It was like being able to steer with finger tips. What are your opinions?
How would you factor in Rodney Dickmans zero-lash sway bar end links? I installed them and the handling felt more responsive in turns, with lighter steering feel. It was like being able to steer with finger tips. What are your opinions?
Similarly to the mounting bushings, they are improving response. You don't have to "push through" the compression of the end link bushings before the forces of the bar really start to build up. I'd imaine that the car would feel more responsive on initial steering input and as the weight first starts to transfer. It would have no effect in steady-state cornering, but WOULD have an effect in the more immediate transmission of bumps through the bar. Your experience seems consistent with my expectations.
I changed mine out to the zero lash ends not to long ago. I have not really given the car hell since doing it but the design is much better than that of the stock stuff. \
Pic for reference Rears:
Fronts:
[This message has been edited by Spadesluck (edited 02-21-2020).]