Nissan 370Z Forum - View Single Post

Brendan · 06-25-2020, 08:11 PM

revised proposal is out. I'm pretty indifferent about the new cars (no a90 supra) but 315 would be fun.

Quote:

Street Touring Category
#28321 Make STU Great Again!
The STAC is seeking member feedback on a more refined proposal to renew interest in STU and modernize the Street Touring ruleset overall. An initial proposal was published in the April 2020 Fastrack and the STAC has further refined that proposal based on input received. There was generally positive feedback and the STAC hopes that the following revisions will address some of the concerns that were received. The STAC highly encourages individuals to write letters with feedback on the revised proposal.
Changes from the previously published proposal are as follows:
• Restricting AWD and mid/rear-engine cars to 295 tires
• An additional allowance for charge pipe replacement as many cars struggle with charge pipe failure with elevated boost levels
• Clutch allowance is available to all vehicles but requires stock flywheel to keep from being a must-do modification
• Toyota Supra is now on the "maybe one day" list of cars as the STAC felt the performance was too much for the current class
The changes are outlined below:
Wheel and Tire Size Changes
14.3 TIRES
Tires must meet the eligibility requirements of the Street category with the following additional restrictions:
Tires shall have a section width up to and including the following (mm):
STR (AWD), STS .................................................. .............................225
STX (AWD), STH (AWD)............................................. .........................245
STR (2WD)............................................. ...........................................255
STU (AWD & 2WD mid- or rear-engine), STX (2WD), STH (2WD)..............265
STU (AWD & RWD forced induction)........................................ ..........295
STU (RWD N/A & FWD).............................................. ...................315
Intercooler and Charge Pipe Allowance Expansion
14.10.C
1. The air intake system up to, but not including, the engine inlet may be modified or replaced. The engine inlet is the throttle body, carburetor, compressor inlet, or intake manifold, whichever comes first.
SCCA Fastrack News July 2020 Page 3
The existing structure of the car may not be modified for the passage of ducting from the air cleaner to the engine inlet. Holes may be drilled for mounting. Emissions or engine management components in the air intake system, such as a PCV valve or mass airflow sensor, may not be removed, modified, or replaced, and must retain their original function along the flow path.
2. STH only: As utilized only on engines originally equipped with forced induction, induction charge heat exchangers (also known as “intercoolers” or “charge air coolers” [CACs]) are unrestricted in size and shape. Air-to-air CACs and radiators for air-to-liquid CACs must be cooled only by the atmosphere except for standard parts. Body panels, fascias, or structural members may not be cut or altered to facilitate CAC installation. Removal of vehicle components to facilitate installation is not allowed. Holes may be drilled for mounting. Factory boost piping may not be modified or replaced.
3. Charge pipes may be modified or replaced. Replacement charge pipes may delete or block off factory pipes designed to enhance intake sounds (“noisemakers”). Modification or deletion of vehicle components (e.g. plastic shrouds, wheel well liners) to permit routing of alternate charge pipes is not allowed.
Boost Controls Allowance
14.10.C
3. Compressor Bypass Valves (CBVs), blow-off valves, and pop-off valves may be replaced or modified.
4. Boost regulation systems, either electronic or mechanical, and electronic fuel cuts referencing boost pressure may be modified, replaced, or removed. This allowance does not allow for changes to the turbocharger or wastegate.
Clutch Allowance
14.10.O
The clutch disk and pressure plate may be modified or replaced.
Transmission Tuning
14.10.P
The Transmission Control Unit (TCU) may be re-programmed. This allowance only applies to modification of transmission behaviors and does not extend to re-programming any other components.
Electronic Differential Tuning
14.10.Q
Electronic differentials may be re-programmed. This allowance only applies to changing differential behaviors and does not extend to re-programming any other components.
Replacement of Differential in AWD vehicles
14.10.K.2
STU, STR, STX, and STH classes: Only standard (as defined in Section 12) limited slip differentials (LSD) are allowed on AWD vehicles. For AWD vehicles that did not come with any type of limited slip differential (including center differential or transfer case), a single aftermarket mechanical LSD may be added. 2WD vehicles may use any mechanical LSD unit. AWD vehicles may substitute one differential (front, rear, or center) with an aftermarket mechanical LSD.
Appendix A Changes to STU Listings
Audi
RS3
RS4
RS4
BMW
228 (2015-2015) 2 Series (non-M) (2014-2020)
SCCA Fastrack News July 2020 Page 4
M235i (2014-2016)
4 series (non-M) (2014-2020)
3 Series (E9x chassis, NOC inc. M3) (2006-2013)
3 series (non-M) (2014-2020)
M2 (except Performance Edition ZL9) (2016-2018)
M3 (2000-2020)
M4 (2014-2020)
M Coupe (2006-2008)
Ford
Focus RS (2016-2017 2018)
Porsche
Cayman S (981) (2013-2016)