I copied this from the GSCA site. Makes it easier to find the rules...
TSA "Turbo stock appearing" TR class qualifying ET 13.2
The TSA TR class is intended to provide a race class for cars that are STOCK APPEARING. Unlike the TSS class where some visible mods are allowed for performance reasons, virtually all of those will not be allowed in this class. It is intended that with the STOCK APPEARING requirement, innovation will develop methods that will push the performance of STOCK APPEARING cars to a level that has not been achieved in the past. In some cases such as exhaust systems where original replacements are no longer available and haven't been for quite some time we will allow "reasonable upgrades". For the sake of these rules the term "stock appearing" does NOT mean similar to, better than, improved, really close, almost identical, should have been like this, what GM really intended, more stock than stock, they made a mistake and this is how my car was shipped, etc. Since the spirit of the class is for STOCK APPEARING cars we really shouldn't have to spell things out in much detail. This means if we can SEE it and it's not how the car was delivered its not allowed. Or put another way if you have to ask if its ok------ its not! [1]
No tools will be used for inspection beyond a light, mirror, ruler, scales and scan tool. No removal of parts or disassembly will be done in tech that requires tools. Cars are subject to re-tech at any time before or after runs. Car must have option sticker on trunk lid with VIN that matches car.
The qualifying ET is based on the factory posted times for a GNX. With poor tires, exhaust, chip and turbo (all allowed in this class) the GNX was able to achieve 13.2 as far back as 1987.
Suspension :
Must retain all original equipment.
NO frame mods or reinforcements.
Stock wheelbase, stock unmodified control arms front and rear with black bushings in original locations.
Since all the cars didn't come with the same body bushing compliment you can have them in all locations as long as they are GM bushings.
No frame braces that didn't come on the car.
No traction bars unless the car is an original GNX and then they must be original.
Rear seat braces are ok as long as they are installed and visible only from the trunk.
8.5 inch 10 bolt GM rear with stock stamped cover unless it is an original GNX. Posi may be added to non posi cars.
Must have stock dimension and diameter sway bars front and rear with black bushings.
Stock appearing brakes, drums back (alum ok), disc front.
Any type stock appearing shocks in stock location----any color ok.
Springs must be single coil design like original stock springs.
No air bags.
Car must sit at one inch of stock ride height. This would be 8" from road surface to frame rail measured at all 4 jacking mounts.
Engine compartment
109 block with no EXTERNAL mods.
All original equipment and sensors intact-no deletions or additions that aren't supported by build tag on inside trunk lid. Original size battery in stock location with original type side terminals and battery cables.
Original type stock appearing water pump.
Original, stock, externally appearing manifold, throttle body (alum or silver in color).
Original appearing starter and 120A CS alternator with stock appearing fan.
Stock accessory bracket with original appearing power steering pump/pulley and AC compressor/pulley
Stock appearing black coil pack.
Grey or black spark plug wires original size/length/diameter routed in original location.
Original GM headers with heat shields intact---may be welded for repair purposes.
Original diameter one piece downpipe (2.5"max)
Original type wastegate---- may be modified to make it adjustable (ie threaded rod).
Original type solenoid (one only) must be only control for wastegate.
Stock appearing 3 bolt turbo must fit under unmodified shield mounted in stock location with stock bracket with stock GM cast inlet bell with vent intact----the vent can be blocked but like everything else it must not appear from the outside to be modified.
Stock appearing MAF (AC molded with down turned plug)
OEM inlet flex hose with no modifications (tape etc)
Stock intercooler with no external mods with stock inlets/outlets mounted with stock brackets in stock location with stock scoop (screen may be removed)
Any size injectors in 6 stock locations.
Stock appearing fuel rail
GM 8445 heads with NO external mods or logos---- installed with GM TTY bolts. Any head gaskets.
Stock appearing unmodified valve covers (must be alum or silver in appearance) installed with 1 oem style cork gasket, NO spacers. Original filler cap and tube on driver side.
Original breather and tubing on pass side.
Stock radiator tanks. Additional cores can be added but support cannot be modified.
Original underhood wiring and loom must be intact with no additions/deletions that aren't supported by option tag-----only exceptions 1-alarm, 2- single relay and wiring for fuel pump "hotwire" upgrade.
AC may be converted to R-134 and must be operational enough to blow colder than ambient.
Powermaster with stock reservoir.
Stock unmodified air box (no holes when installed on car) with snorkel.
NO chrome if GM didn't do it.
Hoses must be black and clamps must be original color.
No engine tiedowns.
Aftermarket engine/tranny mounts ok if they use original mounting holes and black cushions.
Stock unmodified fans in both locations-radiator and crank. Original diameter pulleys and serpentine belt.
Tranny
2004R with no visible external mods except for 2ond servo.
Stock pan and driveshaft---loop ok, any convertor or transbrake as long as it is not visible under or inside the car.
Trans cooler ok as long as it is mounted and plumbed "GNX" style
Tires/wheels
Any matching set of 15" or 16" steel or alum wheels-------must retain original bolt pattern-------front tires must be at least 215 wide ------rear tires must be 275 or less DOT radials-----NO SLICKS
Interior
Full stock appearing interior matching option codes on trunk lid. Original gauge cluster, only addition to gauges is boost (2 1/8 max dia) and it must be pillar, column or console mounted.
Stock shifter
Radio may be upgraded but must fit in stock location with no visible components/parts elsewhere.
All windows must be glass and all door windows must function as normal.
Exterior
Complete car exterior retaining original appearance as it was on the showroom floor.
All bumpers (must be original steel), fillers, panels and lights must be in place.
All body panels must be painted--- no bare metal or primer.
No signs on painted exterior of car. Any signs on windows must be smaller than 1" letters, logos <2" unless they are from state inspection or a factory window sticker.
No fiberglass or ABS body parts except for bumper fillers.
Full size OEM aluminum or steel bumper reinforcements, use of aluminum bumper reinforcements does not have to match VIN tag in trunk.
Bumper shocks must be original steel/unmodified.
No mods to sheet metal, fenders etc.
Repro header panels and trunk spoilers are allowed if they are fitted correctly and look original.
Car may be undercoated.
Fuel system
Factory stock appearing tank, no VISIBLE additions to tank or pumps except for relay and wire upgrade
Replacement lines may be used as long as they are original size and are routed in stock location
233 or 237 regulator with no external mods.
Stock ECM with any chip, no other computers allowed.
Only one O2 and it must be installed in the original location.
Must run gasoline for fuel, no more than 10% oxygenators------any octane ok
No fuel additives, NOS, alcohol or other chemicals allowed
Exhaust
Downpipe must be one piece and attach to stock elbow in stock fashion (ie with donut and spring loaded bolts, downpipe must route in stock location, no flexpipe.
Stock diameter one piece crossover pipe (does not have to neck down on either end)
Stock appearing full length cat must be in stock location-- must be able to pass a 50 state VISUAL inspection
Original design or dual mufflers but must function (muffle) and exit in stock location, must be 2.5 inch or less pipes past "Y" connection at cat. No cutouts.
Minimum weight 3,500 w/driver lbs-------spare tire and jack does not have to be in place when racing or weighing
Purse will be $2900 if there are at least 3 qualifying cars. 1600 first, 800 second and 500 third. As an indicator of the spirit of the class, purse will be doubled for any car if it scores at least ________ [2] in the concours class of the car show. Car must race identical as it appears in the concours with NO changes except for wheels and tires.
Example: car places third in race class and silver in concours, purse of $500 would be doubled to $1000
Richard Clark will be the Race Rules Administrator. Any questions about rules clarification and or interpretation can be addressed to this board or to
richardclark@ami-media.com
Your posts Dennis have been educational and more importantly good reading. Keep em coming. 
