follow ft86club on our blog, twitter or facebook.
FT86CLUB
Ft86Club
Speed By Design
Register Garage Members List Calendar Search Today's Posts Mark Forums Read

Go Back   Toyota GR86, 86, FR-S and Subaru BRZ Forum & Owners Community - FT86CLUB > Technical Topics > Suspension | Chassis | Brakes -- Sponsored by 949 Racing

Suspension | Chassis | Brakes -- Sponsored by 949 Racing Relating to suspension, chassis, and brakes. Sponsored by 949 Racing.


User Tag List

Reply
 
Thread Tools Search this Thread
Old 10-26-2024, 06:14 PM   #1
N_Raged
Senior Member
 
Join Date: May 2019
Drives: 2019 BRZ Sport-Tech RS
Location: Toronto, Canada
Posts: 232
Thanks: 52
Thanked 202 Times in 107 Posts
Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Chassis bracing for STX build - 2019 BRZ

Hello, What are the recommended chassis upgrades for STX class? I have STi tS springs, adjustable Tein Endurapro dampers, a front swaybar, and will have major front and rear camber mods.


I'm having trouble interpreting the SCCA rules around bracing:
Quote:
14.2
G. Strut bars per Section 12 are permitted with all types of suspension, subject to the following constraints:

1. A 2-point strut bar may be added, removed, modified, or substituted, but only with another 2-point strut bar.

2. A triangulated (3-point) strut bar may be removed, modified, or substituted; substitution may be with either a triangulated or a 2-point strut bar. The connection to the chassis (e.g., firewall, bulkhead) must be in the standard location.

3. Lower suspension braces must be attached to the lower suspension pickup point locations on the chassis within 2" (50.8mm) in any direction of the actual suspension attachment to the chassis.

4. Except for standard parts, no connections to other components are permitted. Additional holes may be drilled for mounting bolts. Only "bolt-on" attachment is permitted. Interior trim panels may be modified to allow installation of strut bars. Holes or slots may be no larger than necessary and may serve no other purpose. This does not permit any modifications to the frame or unibody beyond the allowed mounting holes.

H. Longitudinal (fore-aft) subframe connectors ("SFCs") are permitted with the following restrictions:

1. They must only connect previously unconnected boxed frame rails on unibody vehicles.

2. Each SFC must attach at no more than 3 points on the unibody (e.g., front, rear, and one point in between such as a seat mount brace or rocker box brace).

3. SFCs must be bolted in place and not welded.

4. No cutting of OE subframes or floorpan stampings is permitted. Drilling is permitted for mounting bolts only.

5. No cross-car/lateral/triangulated connections directly between the driver’s side and passenger’s side SFCs are permitted. Connections to OE components such as tunnel braces or closure panels via bolts are allowed and count as the third point of attachment. No alteration to the OE components is permitted.
When it comes to underbody bracing, what can I do or cannot do for STX? For example looking at the TRD member brace set, or the various Cusco underbody braces, which pieces are allowed?

The rules around strut bars is clear. My car already has a stable front end thanks to the front sway bar so I don't think I would want a front tower bar to potentially add more understeer. My rear on the other hand is a bit snappy and I can get into a tank slapper sometimes from really abrupt transitions - would a rear tower bar help here? Or should I prioritize Whiteline rear subframe inserts or even a rear sway bar?

Anything else I should be considering?
N_Raged is offline   Reply With Quote
Old 10-26-2024, 09:42 PM   #2
whataboutbob
AutoX-10/10ths every run
 
whataboutbob's Avatar
 
Join Date: Jun 2012
Drives: 2013 Scion FR-S AT Firestorm
Location: San Marcos, CA, USA
Posts: 2,584
Thanks: 4,780
Thanked 1,859 Times in 1,013 Posts
Mentioned: 79 Post(s)
Tagged: 0 Thread(s)
Garage
I'd be looking at steering inputs, tire choice, tire pressure, and rear swaybar first.
whataboutbob is offline   Reply With Quote
The Following 2 Users Say Thank You to whataboutbob For This Useful Post:
NoHaveMSG (11-10-2024), Spuds (11-06-2024)
Old 10-30-2024, 08:56 PM   #3
DocWalt
Senior Member
 
DocWalt's Avatar
 
Join Date: Oct 2013
Drives: '22 BRZ
Location: PA
Posts: 1,899
Thanks: 2,363
Thanked 1,568 Times in 811 Posts
Mentioned: 24 Post(s)
Tagged: 2 Thread(s)
None of those braces are going to do anything worthwhile.
DocWalt is offline   Reply With Quote
The Following 2 Users Say Thank You to DocWalt For This Useful Post:
NoHaveMSG (11-10-2024), RT-BRZ (10-30-2024)
Old 11-01-2024, 12:33 PM   #4
N_Raged
Senior Member
 
Join Date: May 2019
Drives: 2019 BRZ Sport-Tech RS
Location: Toronto, Canada
Posts: 232
Thanks: 52
Thanked 202 Times in 107 Posts
Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Okay will stick to rear subframe inserts and rear sway bar then.
Thank you all.
N_Raged is offline   Reply With Quote
 
Reply

Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
Chassis Bracing that's worth looking at? HatchirokuV2.0 Suspension | Chassis | Brakes -- Sponsored by 949 Racing 5 09-03-2015 12:44 PM
GTSPEC Chassis Bracing - MASTER CATALOG - NEW PRODUCTS from 86Insider.com 86_Insider Brakes, Suspension, Chassis 3 09-29-2013 09:57 PM
GTSPEC Chassis Bracing - MASTER CATALOG - NEW PRODUCTS - BEST PRICING - 86Insider.com 86_Insider Brakes, Suspension, Chassis 10 09-08-2013 02:15 PM
TOM's Chassis Bracing Released Hanakuso Suspension | Chassis | Brakes -- Sponsored by 949 Racing 16 11-08-2012 01:04 PM


All times are GMT -4. The time now is 04:48 AM.


Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2024, vBulletin Solutions Inc.
User Alert System provided by Advanced User Tagging v3.3.0 (Lite) - vBulletin Mods & Addons Copyright © 2024 DragonByte Technologies Ltd.

Garage vBulletin Plugins by Drive Thru Online, Inc.