Turbo Street Limited – TSL (Proposed Rules )
Engine Management & Fuel System
Tires & Wheels
- Qualifying ET is 10.20 or quicker.
- Heads-up pro tree start and pro ladder.
- Winner and runner-up are subject to re-weigh and re-tech immediately after final round or at any other time.
- Any entrant caught trying to deliberately break the rules will be disqualified from the class.
- Seat belts, 2 high/low beam headlights [inner optional], rear lights and horn must be operational.
- Car must possess all applicable safety equipment for potential ET/speeds attained, roll bar or certified cage.
- Minimum car weight w/driver must be at least 3,400 pounds.
- Complete stock, painted Turbo Regal/Grand National body required. Use of fiberglass for replacement parts allowed
- Stock wheelbase required (108.0" measured).
- Engine/firewall must be in stock location.
- Stock operating glass windows and windshield required no lexan.
- Factory stock suspension locations required w/any type stock location shocks.
- Any suspension stabilizer/reinforcement bars or traction enhancing devices are allowed.
- Swaybars may be removed.
- No ladder bars.
- Outer frame rails notching allowed. Inner frame rails remain in the stock location.
- Reinforcement at inner rear frame rail allowed.
- No quarter panel modifications except rolled inner lip.
- Minor modifications to stock rear wheel wells to permit inside clearance to frame (no mini-tubs).
- Factory stock appearing inner front wheel wells required. Trimming allowed for downpipe clearance.
- Parachutes OK
- Brake system line locks allowed.
- Brake system may be either Power Master, vacuum boost operated, or manual brakes.
- Drive shaft safety loop required.
- Driver's name and club decal on side/quarter windows allowed.
- Sponsor/vendor decals are acceptable.
- Stock, Stage 1 or 2 Buick V6 off-center or on-center cylinder blocks are allowed. Aluminum block ok
- Iron, Stage 1, aluminum M&A, Champion, or T/A cylinder head castings allowed.
- No Stage 2 iron or aluminum heads allowed.
- Any valve covers and oil pan allowed.
- No dry sump-oiling systems. External pumps OK
- Factory stock style intake manifold required. Aftermarket intakes allowed, Bowling Green, Champion etc.
- Factory stock plenum w/spacer or aftermarket cast aluminum intake plenum allowed. Any size single modified stock or aftermarket throttle body allowed in stock location. Single throttle plate only.
- Any type stock location exhaust headers are allowed. Welded in EGT gauge probe bungs are allowed.
- Any single or dual exhaust system allowed. Must have functional muffler and exit behind rear edge of door. (4" max size).
- UP to 4 inch downpipe size is allowed from turbo. It must be routed down through the stock location. No flex pipe allowed.
- One (1) 4-bolt turbo allowed.Must have stock orientation Note: The largest allowable turbo compressor wheel is up to and including 76mm. Maximum opening size anywhere on the compressor housing inducer must be less than 77.50mm.
- Compressor housings limited to ~4" air inlet and 3" outlet
- Must fit an unmodified T-O4 gasket
- Any wastegate configuration acceptable, external wastegate(s) may be plumbed back into the exhaust system, or externally dumped.
- Any stock location or front mount air to air intercooler is allowed.
- No liquid intercoolers, intercooler external spray cooling or add-on cold boxes allowed.
Engine Management & Fuel System
- Stock or modified stock ECM, aftermarket fuel management system are allowed (DFI, Fel-Pro, Motec, etc.).
- MAF optional.
- Any air induction system allowed. No hoodscoops
- Any fuel pump(s) configuration/location allowed.
- Voltage increasing and fuel pump hot wiring devices are allowed.
- Any fuel lines allowed.
- Any fuel rails allowed.
- Any type fuel pressure regulator allowed. Any fuel injectors allowed 7 maximum. The 7th injector MUST get its fuel supply from the fuel rail.
- Factory stock fuel tank w/sump addition or a fuel cell is allowed.
- Gasoline fuel only, no additives, alcohol, or nitrous oxide injection allowed.
- A/C and heating equipment may be removed.
- Power steering operational w/belt in stock location or manual box.
- Stock alternator operational w/belt in stock location. Relocation brackets allowed as long as alternator is still on driver's side, front of engine.
- Stock water pump operational w/belt in stock location or electric pump.
- Any engine compartment dress-up allowed.
- Battery may be in any location and installation must comply with NHRA regs.
- Any stock type/location electric engine cooling fan(s) allowed.
- Any stock or replacement radiator in stock location allowed [stock core support req'd].
- Any GM automatic transmission allowed. (200-4R, TH400, etc.)
- Any torque converter allowed.
- Any transmission oil cooler and pan allowed.
- Transmission brake allowed.
- Any stock width differential housing allowed, +/- 1" allowance.
- Limited-slip differentials or spool allowed.
- Any gear ratio w/factory stock or reinforced differential cover allowed.
Tires & Wheels
- Any matched set of four (4), 15” diameter chrome steel or aluminum wheels allowed.
- Rear drag slicks w/sidewall designation up to and including 29.5” x 10.5” – 15”. No "W" tires allowed. Rear DOT street tires w/sidewall designation up to and including a 29.5” x 12.5” – 15” size tires are allowed.
- Max width on rear tire is 10.9" at 10 psi. Shaving the tire to achieve this is permissible
- Front tire footprint must be at least 3.5" wide.
- Full stock appearing interior required. Rear seat optional, area must be carpted if removed, no bare paneling.
- Race seats are allowed if seats are upholstered to match the factory interior AND MUST BE attached to the rear crossbar of the roll cage.
- Any transmission shifter allowed.
- Any additional aftermarket gauges allowed.
- A maximum of 2 hood mounted gauges are allowed.