Pennock's Fiero Forum
  Technical Discussion & Questions
  Adjustable Upper Control Arms Yes or No

Post New Topic  Post A Reply
Email This Page to Someone! | Printable Version


next newest topic | next oldest topic
Adjustable Upper Control Arms Yes or No by Larryinkc
Started on: 06-29-2023 11:46 AM
Replies: 5 (671 views)
Last post by: Wererabbit91 on 07-30-2023 12:41 PM
Larryinkc
Member
Posts: 697
From: Kansas City, MO USA
Registered: Nov 2012


Feedback score: (3)
Leave feedback

Rate this member

Report this Post06-29-2023 11:46 AM Click Here to See the Profile for LarryinkcSend a Private Message to LarryinkcEdit/Delete MessageReply w/QuoteDirect Link to This Post
I have a pair of West Coast Fiero adjustable upper control arms and need some help with deciding if installing them is a good idea or not. Let me know what you think. THANKS in advance.




IP: Logged
PFF
System Bot
olejoedad
Member
Posts: 19771
From: Clarendon Twp., MI
Registered: May 2004


Feedback score: (5)
Leave feedback





Total ratings: 207
Rate this member

Report this Post06-29-2023 01:28 PM Click Here to See the Profile for olejoedadSend a Private Message to olejoedadEdit/Delete MessageReply w/QuoteDirect Link to This Post
Other than the bling factor, if you're not racing your car and fine tuning the alignment.....is there any point in it?

You would likely need to remove the wheel for anyone to see them.

In case of an accident ( even if it's not your fault), would your insurance coverage be denied?
IP: Logged
pmbrunelle
Member
Posts: 4594
From: Grand-Mère, Québec
Registered: Sep 2008


Feedback score: N/A
Leave feedback





Total ratings: 63
Rate this member

Report this Post06-29-2023 06:17 PM Click Here to See the Profile for pmbrunelleSend a Private Message to pmbrunelleEdit/Delete MessageReply w/QuoteDirect Link to This Post
I think it's a good idea to fine-tune and figure out what you want.

Once you know what you want, then it's probably ideal to build a fixed set of arms for service, that cannot become de-adjusted.
IP: Logged
fieroguru
Member
Posts: 12479
From: Champaign, IL
Registered: Aug 2003


Feedback score:    (45)
Leave feedback





Total ratings: 260
Rate this member

Report this Post06-29-2023 10:13 PM Click Here to See the Profile for fieroguruSend a Private Message to fieroguruEdit/Delete MessageReply w/QuoteDirect Link to This Post
Adjustable upper control arms are great, if you only look at what you are trying to accomplish with them. More caster, easy. More camber, easy.

The challenge comes in what else changes with the suspension geometry as a result of the upper a-arm adjustment.

Rock the knuckle back to dial in more caster - raises the outer tie rods vs the rack and upper/lower ball joints and makes bump steer worse.
Shorten the a-arm to dial in more camber, now the relationship between the pivot points of the bushings, tie rods and ball joints change. This can cause bump steer as well as changes with the roll center.

Knuckles, A-arms and steering rack all have to be designed or modified to work together.
IP: Logged
sleek fiero
Member
Posts: 414
From: British Columbia
Registered: Aug 2022


Feedback score: N/A
Leave feedback

Rate this member

Report this Post06-29-2023 11:13 PM Click Here to See the Profile for sleek fieroSend a Private Message to sleek fieroEdit/Delete MessageReply w/QuoteDirect Link to This Post
Larry give them a try. You will never know whether they are anything you want unless you try them . I have the fiero store anti bump steer a arms on mine and I would not trade them for anything..Always there are new upgrades coming on and the only wa you will know if the are good is if someone tries them. sleek
IP: Logged
Wererabbit91
Member
Posts: 38
From: STERLING HEIGHTS, MI
Registered: Aug 2019


Feedback score: N/A
Leave feedback

Rate this member

Report this Post07-30-2023 12:41 PM Click Here to See the Profile for Wererabbit91Send a Private Message to Wererabbit91Edit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by fieroguru:

Adjustable upper control arms are great, if you only look at what you are trying to accomplish with them. More caster, easy. More camber, easy.

The challenge comes in what else changes with the suspension geometry as a result of the upper a-arm adjustment.

Rock the knuckle back to dial in more caster - raises the outer tie rods vs the rack and upper/lower ball joints and makes bump steer worse.
Shorten the a-arm to dial in more camber, now the relationship between the pivot points of the bushings, tie rods and ball joints change. This can cause bump steer as well as changes with the roll center.

Knuckles, A-arms and steering rack all have to be designed or modified to work together.


I agree with fieroguru and what olejoedad said. I recently installed a set of these on my Fiero. https://www.fiero.nl/forum/Forum1/HTML/100494.html My car is designed to be a track capable car and I wanted to be able to increase the camber and caster on it to correct for lowering it 1.5inches. So far I have settled on settings close to stock for the exact reasons Guru said. Driving around on Michigan roads the car is darty going over bumps and with no bushing material in the upper mounts now, you feel everything! Every joint, crack, or tar sealant strip. On nice smooth roads and tracks it handles great now, but normal roads the ride is significantly harsher. I'm okay with this for now, but I'm already thinking of how to redesign it with some bushing material between the upper arm and chassis.
So I only recommend this modification for those who know exactly what they want to gain from it, and are ready to accept the increased ride harshness and resist the temptation to constantly try to fine tune them. I hope this helps!


IP: Logged

next newest topic | next oldest topic

All times are ET (US)

Post New Topic  Post A Reply
Hop to:

Contact Us | Back To Main Page

Advertizing on PFF | Fiero Parts Vendors
PFF Merchandise | Fiero Gallery
Real-Time Chat | Fiero Related Auctions on eBay



Copyright (c) 1999, C. Pennock