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STX Rules and Setup Questions

As a former Impound Chief, Tech Chief, and General Rules Nazi, I am opening this thread to help people understand the Rules for STX in SCCA Solo competition.
If you have questions on what may or may not be legal ... Post away.. there are quite a few 'experts' here on the site that will be available to help you understand what your getting into..

Some General Rules to consider:

-The Car is classed in STX Class, Which has a pretty big following since most of the mods that are allowed are pretty much the mods your doing anyways..
-STX is a Street Tire Class.. so your tires have a minimum of 200 treadwear, and they can be no wider than a 265 on a 9in wheel.
-Suspension Swaps are allowed....Springs Swaybars, Coilovers, and Bushings...
-Exhaust mods are allowed including the Header, overpipe, Midpipe and catback with an aftermarket system...the only stipulation is that you must have a cat in your system.. you can Delete the Factory Cats and replace it with a Hi-flo unit as long as its within 6 in of the furthermost cat (the back one)...
-Any Intake System can be used as long is it mounts to the OE Throttle body.
-Any Engine management Can be used to achieve optimum tune
-Aftermarket BBK as long as they are the same size or larger than stock. Brake Lines can be changed to Stainless with any fluid.
-Lightweight battery as long as it puts out the same voltage. and you can re-locate it if needed to the trunk area.
-Engine and tranny mounts as long as they are NOT solid
-Any LSD.
-Any Seats can be used but there is a minimum weight.(25lbs for the whole assy)

What CAN'T BE DONE:
-no engine internals
-no Tranny/rear diff Gear changes
-no throttlebody work
-Radiators have to comply with Stock

This should get most of your started. have any questions.. Don't hesitate to post them up.. Glad to help

Bill

other Vehicles you will compete with in STX:
-02 to 08 WRX
-Mazda RX8/Mazdaspeed 3,6,Protege'
-BMW 3series NON M/128
-Mustang various years
-Honda Integra Type R
-Chevy Camaro/Cobalt SS
-Audi A3/A4/TT Quattro
-Eagle/Mitsu Talon/Eclipse AWD
-Honda Civic Si
-Inifiniti G35
-Lexus IS300
-Mini Cooper S and S JCW
-Nissan 300 ZX non-turbo/Sentra SER SPec-V
-Pontiac Firebird
-VW Beetle/Golf/GTI/Jetta/Passat 2.0T and a R32
-Volvo C30

those are what is eligible for competition..
The BMWs are super Competitive as well as some WRX's..I have even seen an R32 fairly competitive...

Bill

I will be adding Sections of the rules for ST...So you can always refer to this thread if you get lost..:)

Quote:

14. STREET TOURING CATEGORY
The Street Touring category of vehicle modifications is meant to fit between
the current Stock and Street Prepared categories. This category
provides a natural competition outlet for auto enthusiasts using affordable
sports cars and sedans equipped with common suspension and
engine modifications compatible with street use.
Under the provisions of Section 1.1 of these rules, Regions are free
to allow any other version of the ST concept which meets their local
needs. In particular, some leeway in the area of bodywork allowances
(e.g., wings/spoilers beyond those allowed in 14.2.F) is encouraged at
Regional Solo® events.

Quote:

14.1 AUTHORIZED MODIFICATIONS
All Solo® Rules Stock Category allowances, plus all allowances contained
in 14.1 through 14.10.
14.2 BODYWORK
A. Pedal cover kits and other interior cosmetic accessories may be
added. “Dress-up” items such as chrome dipsticks and non-standard
filler caps are permitted, provided they serve no other purpose.
B. The driver and front passenger seats may be replaced, with the following
restrictions: The seating surface must be fully upholstered.
The top of the seat, or an attached headrest, may not be below the
center of the driver’s head. The seat, including mounting hardware,
must weigh at least 25 pounds and must be attached using the OE
body mounting holes/studs. Additional mounting points may be added.
C. Factory rub strips, emblems, mud flaps, bolt-on front valance lips/
spoilers, and fog lights (except those integral to a headlight or turn
signal) may be removed. Rear wings may be removed so long as the
vehicle retains any federally-mandated third brake light.
D. Alternate steering wheels are allowed except that steering wheels
with an integral airbag may not be changed.
E. Fenders may not be cut or flared but the inside lip may be rolled to
gain additional tire clearance. (The outer fender contour may not be
changed.) Plastic and rubber wheel well splash shields may be modified
for tire clearance and to accommodate a rolled inside fender lip.
The modifications may serve no other purpose (e.g. air intake, brake
ducts, etc). No other changes to the stock fenders or wheel wells are
permitted.
F. Addition of spoilers, splitters, rear wings, bumper covers, valances,
side skirts, and non-functional scoops/vents is allowed provided that
either:
1. It is a production part which is standard or optional equipment of a
US model of the vehicle.
82 — 2012 SCCA® National Solo® Rules
2. It is listed in the vehicle manufacturer’s US accessory catalog
for that vehicle for normal highway use. This does not allow for
parts sold through a manufacturer’s performance catalog (e.g.,
Ford Racing, HPD, MazdaSpeed, Mopar Performance, Mugen,
NISMO, SPT, TRD, etc).
Parts must be installed as directed by the manufacturer. Exact replicas
(including weight) from alternate sources are also permitted.

some more..:)

So... What are you guys going to run for spring rates?

I think I'm going to run higher rear rate, keeping in line with what the factory did, but will probably dial back % difference.

I've put RaceCompEngineering springs on the factory struts - for now.

7K Front 6k rear...

Gathering a selection of springs from 6k up to 10k in .5k increments..
but right now.. not needed as the car is pretty balanced like it sits..

might try 8.5k front with 7.5k rear for testing purposes..... but seriously not needed right now..

Bill

I just want to be clear. Currently e85 is still legal... but that maybe changing soon correct?

Quote:

Originally Posted by feldy (Post 652024)

I just want to be clear. Currently e85 is still legal... but that maybe changing soon correct?

yes... correct.. E85 is out for comment right now.. no decision has been made yay or nay. in regards to it right now.. I personally am going to tune to E85 until I am told different..:)

Supercharger ok?
Catless headerback ok? There is still a factory cat in the header.

Supercharger not ok.

You must have at least one cat within 6" of one of the original locations in your exhaust.

Quote:

Originally Posted by Scooby South (Post 648525)

...the only stipulation is that you must have a cat in your system..

Our cars have two cats - in the header and the front pipe. I was hoping having one of the two factory cats would suffice in case you run a catless front pipe.

Quote:

Originally Posted by Amadeus (Post 656535)

Our cars have two cats - in the header and the front pipe. I was hoping having one of the two factory cats would suffice in case you run a catless front pipe.

the way its setup... you can run one or the other.. Personally I am going to run a Catless header...overpipe and catted midpipe and open cat-back with a turn down.. if you wanted to you can run a Catted header, overpipe and non catted midpipe.. Both Achieve the same goal..and Time will tell which is more Efficient.. :)

Bill

Quote:

Originally Posted by Scooby South (Post 656551)

the way its setup... you can run one or the other..

Cool. I didn't want to buy another front pipe. Thanks