Comparison of permitted modifications in SCCA classes

Note on using this list:  

One example:  Wheels of stock size (same diameter and width, with offset within 0.25" of stock) are allowed for Stock so this item is listed as "Y" for stock.  These wheels are also allowed on Street Prepared, Street Modified, etc. cars, so it's also listed "Y" for them.  However, Street Prepared also allows tires of any diameter, width, or offset so that item, too, is listed as "Y."

Permitted preparation items

Solo

Stock Street Prepared Street Modified Prepared STS STX
General
Option package swap (same model & year Y Y Y Y Y Y
Air conditioning removal   Y Y Y Y Y
Update/Backdate (P Appendix A)       Y    
Update/Backdate (SP Appendix A)   Y Y   Y Y
Body
Driver Restraints Y (stock must also be retained Y (stock must also be retained Y (stock must also be retained Y Y (stock must also be retained Y (stock must also be retained
Rear spoiler   Y (limited) Y Y Y Y
Accessories, gauges, and indicators Y Y Y Y Y Y
Hood straps or fasteners Y Y Y Y Y Y
Fuel Tank Cap Y Y Y Y Y Y
Folded Windshields (if folding is stock) Y Y Y Y Y Y
Welded Roll Bars Y Y Y Y Y Y
Bolted-in Roll cage Y Y Y Y Y Y
Add tow bar brackets Y Y Y Y Y Y
Remove items not held by permanent factory fastener Y Y Y Y Y Y
Fenders & bumpers modified for tire clearance   Y Y Y    
Strut bars, transverse between top or bottom of strut towers   Y Y Y Y Y
Spoilers and cosmetic trim pieces   Y Y Y    
Welded roll cages   Y Y Y    
Fuel cell +/- 20% of original capacity and no more than 6" from the stock location   Y Y Y    
Substitute pedal covers   Y Y Y Y Y
Front spoiler   Y Y Y Y Y
Fully padded, upholstered seats with reclining backs   Y Y Y Y Y
Roll inside lip of fenders   Y Y Y Y Y
Any fully padded and upholstered front seat   Y Y Y    
Trim Removal     Y Y Y Y
Chassis reinforcement       Y    
Frame reinforcement       Y    
Subframe reinforcement     Y (Subframe connectors without cross bracing) Y    
Firewalls altered for moutning headers, carburetors, electrical lines, and fluid carrying lines       Y    
Bumpers may be removed       Y    
Interior trim may be removed       Y    
Any driver seat       Y    
Doors may be pinned       Y    
Windows may be replaced with polycarbonate       Y    
Window channels may be removed       Y    
Window winding mechanisms may be removed       Y    
Closed cars:  Side windows may be removed       Y    
Open cars:  All windows and windshields may be removed       Y    
Windshield safety clips and rear window safety straps permitted       Y    
Inner fender panels may be altered, replaced, or removed       Y    
Rear inner fender panels may be altered, replaced, or removed.       Y    
Fuel tank replacement       Y    
Replacement hood     Y Y    
Replacement fenders     Y Y    
Replacement deck lid     Y Y    
Other replacement component body parts     Y Y    
Removal of mirrors       Y    
Lightened door       Y    
lights may be removed       Y    
Ducting from removed lights may be installed       Y    
Removal of factory trim     Y Y Y Y
Remove all seats       Y    
Trailer hitch added Y Y Y   Y Y
Alternate steering wheels +/- one inch (no changes if airbag) Y Y Y      
Any alternate steering wheel   Y Y   Y (No changes if airbag Y (No changes if airbag
Spoilers, body kits, wings.     Y   Y Y
Replacement wings     Y      
Replacement front fascia     Y      
Replacement Rear fascia     Y      
Replacement side skirts     Y      
Replacement fender flares     Y      
Wings attached to rear deck     Y      
Remove rear passenger seat     Y      
Wheels
Spacers Y (to correct offset) Y Y Y    
OEM size Y Y Y Y Y Y
Offest to +/- 0.25 inch Y Y Y Y Y Y
Any diameter, width, or offset   Y Y Y    
Wheels up to 7.5" width, any diameter or offset.   Y Y Y Y Y
Any wheel not exceeding Appendix A size       Y    
Any wheel mounting stud or bolt   Y (Wheel studs may be changed for bolts/nuts) Y (Wheel studs may be changed for bolts/nuts) Y    
Center lock wheels and hubs permitted       Y    
Tires
OEM Tires Y Y Y Y Y Y
DOT approved Race Rubber Y Y Y Y    
Any diameter or width tires Y (must fit over stock wheels) Y Y Y    
All tires meeting safety requirements       Y    
Tires up to 225 mm section width Y (Over stock size rims) Y Y Y Y Y
Must be available by April 30th Y Y Y   Y  
Must be available in 6 sizes and 4 diameters Y Y Y      
Must have non-zero tread depth Y Y Y   Y Y
Tires must be 140 treadwear or higher       Y Y
Shock Absorbers
Adjustable spring perches Y (welded at stock height) Y
Bump stops altered or removed Y (altered to facilitate aftermarket shocks Y Y Y Y Y
Aftermarket shock absorbers, no more than 2 external adjustments Y Y Y Y Y Y
External reservoirs Y Y Y Y Y Y
Drill holes to mount external reservoirs (no other purpose) Y Y Y Y Y Y
Drill holes to route lines to external reservoirs (no other purpose) Y Y Y Y Y Y
Any shock absorber bushing (not offset) Y Y Y Y Y Y
Lever type shock absorbers may be replaced with tube type   Y Y Y    
Any shock absorber provided it uses original attachment points   Y Y Y Y Y
Coil overs permitted   Y Y Y Y Y
Any shock absorbers may be used     Y Y    
Mounting points may be changed       Y    
Suspension
Any springs   Y (same type as stock) Y (same type as stock) Y Y (same type as stock) Y (same type as stock)
Any torsion bars   Y (same type as stock) Y (same type as stock) Y Y (same type as stock) Y (same type as stock)
Use of shims, special bolts or removal of metal to enlarge mounting holes to change alignment settings Y (if approved by factory for non-competition purposes) Y Y Y Y Y
Alternate front sway bars Y Y Y Y Y Y
Adjustment through design range Y Y Y Y Y Y
Any sway bars   Y Y Y Y Y
Spacing blocks to adjust ride height   Y Y Y Y Y
Leaf spring shackles to adjust ride height   Y Y Y Y Y
Torsion bar levers to adjust ride height   Y Y Y Y Y
Alternate spring perches (on struts)   Y Y Y Y Y
Spring spacers   Y Y Y Y Y
Alter suspension bump stops   Y Y Y    
remove suspension bump stops   Y Y Y    
Replace suspension bushings with non-metallic   Y Y Y Y Y
Adjustable camber plates on strut type vehicles   Y Y Y Y Y
Suspension stabilizers (connecting axle or De Dion to the chassis)   Y Y Y Y Y
Changes in alignment parameters from using allowed components   Y Y Y Y Y
Camber kits on other than McPherson struts   Y Y Y Y Y
Any spindles       Y    
Any hubs       Y    
Any bearing carriers       Y    
Any stub axles       Y    
Suspension control arms may be reinforced, modified or replaced       Y    
Suspension pick-up points may be relocated.       Y    
Strut front suspensions may convert to double A-arm       Y    
Independent rear suspensions may be replaced with live axle or closed tube beam.       Y    
Any suspension bushings       Y    
Steering arms may be modified, reinforced or substituted       Y    
Pitman arms may be modified, reinforced, or substituted       Y    
Unrestricted suspension using using original attachment points     Y Y    
Brakes
Brake pads and linings Y Y Y Y Y Y
steel brake lines on cars manufactured before 1992 Y Y Y Y Y Y
Alternate brake bleeder fittings Y Y Y Y Y Y
Alternate DOT approved brake lines   Y Y Y Y Y
Any brake line   Y Y Y    
Any master cylinder   Y (Single dual-circuit Cylinder, not multiple separate cylinders) Y Y    
Any vacuum booster   Y Y Y    
Any proportioning valve   Y Y Y    
Any brake mounted in original position     Y (metal rotors) Y   Y (rotors & calipers, must use original attachment points)
Servo assist modified, removed, replaced, or added       Y    
Hand brake and operating mechanism may be removed       Y    
Cross drilled or slotted rotors     Y Y Y Y
Air cooling ducts   Y Y   Y Y
"Safety Brakers" such as "Brake Guard System"     Y      
Electrical
Any driver operated electrical starter   Y (original position) Y (original position) Y    
Any spark plugs Y Y Y Y Y Y
Any spark plug and high-tension wires Y Y Y Y Y Y
Any ignition coil Y Y Y Y Y Y
Cars before 1/1/68, Any ignition system used with a standard distributor Y Y Y Y Y Y
Any ignition setting   Y Y Y    
Battery make model and size change   Y Y Y Y Y
Relocation of the battery   Y Y Y Y Y
Any ignition system except magneto       Y    
Generator/alternator may be removed       Y    
Electrical components unrestricted       Y    
Engine
Any carburetor   Y Y Y (some limits)    
Any fuel injection   Y Y Y (some incur weight penalty)    
Intake and exhaust port matching   Y (1" from opening) Y (1" from opening) Y    
Alternate air filter elements Y Y Y Y Y Y
Rebored to manufacturers first standard overbore (not to exceed 0.020") Y Y Y Y Y Y
Cat back exhausts Y Y Y Y Y Y
Any oil filter Y Y Y Y Y Y
Water expansion tanks Y Y Y Y Y Y
Oil Catch Can Y Y Y Y Y Y
Thermostats Y Y Y Y Y Y
Silicone replacement hoses Y Y Y Y Y Y
New valve seats for older cars that used leaded fuel Y Y Y Y Y Y
Any oil or grease Y Y Y Y Y Y
Standard type lubrication system   Y Y Y    
Alternate oil pan   Y Y Y    
Accusump systems   Y Y Y    
Oil coolers   Y Y Y    
Heat Shields   Y Y Y    
Any intake manifold   Y Y Y    
Any air cooled intercooler   Y Y Y    
Change or remove air cleaners   Y Y Y    
Modify or remove emission control devices   Y Y Y    
Alternate fuel lines up to 1/2" diameter   Y Y Y    
Exhaust manifolds/headers   Y Y Y Y (emissions legal) Y (emissions legal)
Muffler systems (end behind driver)   Y Y Y    
single axis torque suppression device   Y Y Y    
Alternate engine fan and fan shroud   Y Y Y    
Overbore to 0.0472   Y Y Y    
Balance rotating parts   Y Y Y    
Cylinder heads milled to amount specified in workshop manual or to 0.010 if unspecified   Y Y Y    
Fuel pressure regulator (in lieu of electronic management)   Y Y Y Y Y
Setting of ignition settings on factory adjustable systems   Y Y Y Y Y
Any accessory pulleys of same type that are not dampener/balancers   Y Y Y Y Y
Engine lightened     Y Y    
Engine components modified (remain identifiable as original)     Y Y    
Intake manifold ported and polished     Y Y    
Fuel injection system (some incur weight penalty)     Y (no penalty) Y    
Any fuel lines     Y Y    
Cool can     Y Y    
Any fuel pumps and regulator     Y Y    
Specified alternate cylinder heads     Y (any) Y    
Machining or alternate/removed head gasket to alter compression ratio     Y Y    
Any camshaft     Y Y    
Any cam chains, gear, belts, or sprockets     Y Y    
Added timing chain/belt tensioner     Y Y    
Any metal valves     Y Y    
Any rocker arms and shafts     Y Y    
Any metal pushrods     Y Y    
Any cam followers     Y Y    
US Produced V6 and V8 engines overbore to 0.060"     Y Y    
Cylinder sleeves for repair     Y Y    
Any crankshaft main bearing caps     Y Y    
Milling the block to increase compression ratio     Y Y    
Machining block to add crankshaft oil seals and related attachment devices     Y Y    
Any pistons, clips, and or retainers and piston rings     Y Y    
Any ferrous connecting rods     Y Y    
Any engine driven oil pump     Y Y    
Dry sump system     Y Y    
Any vent or breather on the engine, but not connected to the exhaust     Y Y    
Exhaust unrestricted     Y Y    
Any fasteners and "expendable" components     Y Y    
Concentric bushings where none originally exist     Y Y    
Any gaskets     Y Y    
Any alternator/generator, crankshaft, and water pump pulleys.     Y Y    
Any torque suppression device     Y Y    
Any motor mounts     Y Y    
Rotary: new eccentric shaft of same basic material     Y Y    
Rotors of same material and number of lobes     Y Y    
Any water radiator     Y Y    
Sealing/shrouding airflow between grill opening and radiator     Y Y    
Electric water pumps     Y Y    
Alternate mechanical water pumps     Y Y    
VTEC controllers     Y Y Y Y
High flow catalytic convertors     Y Y   Y
O rings to replace cylinder head gasket     Y Y    
Reprogrammed ECU   Y (changing items with allowed mechanical alteration) Y   Y (no changes to traction control or boost) Y (no changes to traction control or boost)
Electronic components between ECU and sensors   Y (changing items with allowed mechanical alteration)   Y Y
Intake water injection systems   Y Y      
Any engine with block from same manufacturer with size limits and street fuel     Y      
Drivetrain
Scattershields Y Y Y Y Y Y
Reverse gear lockout Y Y Y Y Y Y
Any metal clutch   Y Y Y    
Any mechanical shift linkage   Y Y Y    
Limited slip differentials   Y Y Y    
Any transmission oil cooler   Y Y Y    
Axle/halfshaft/driveshaft retention devices   Y Y Y    
Short throw shift kits   Y Y Y Y Y
Any non-sequential manual transmission       Y    
No functional reverse gear       Y    
Altering transmission tunnel/cover for fit       Y    
Alternate driveshafts       Y    
Any gear ratio       Y    
Any axle tube       Y    
Any final drive housing       Y    
Any drive axle shaft       Y    
Any drive axle bearings       Y    
Any drive axle bearing carriers       Y    
Any drive axle hubs       Y    
Any Universal/CV joints       Y    
Breathers shall have catch cans       Y    
Factory LSD on AWD cars       Y Y (viscous, also includes FWD) Y
Adding one LSD to cars that don't have an LSD       Y   Y
Alternate motor mounts sold by vehicle manufacturer or its competition subsidiary       Y   Y

Many thanks to the people whose input has helped me correct errors to this listing.

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