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Limited Street Presented by:


Limited Street Presented
By: ??????????????

Limited Street is a heads up class reserved for rear wheel drive passenger cars and trucks. Several key performance restrictions including stock suspension, power adder limitations and tire restrictions will try to level the playing field for competitors.


LADDER:
Pro Ladder based on qualifying order (1 vs.16, 2 vs.15, etc.)

RUN FORMAT:
All-run, no limit on car count.

STAGING PROCEDURE:

Blue Light active, courtesy stage. This means pre-staging and staging by one car is NOT allowed unless it is on a bye run. The allowed procedure is both competitors pre-stage, then one stages and the other stages within seven seconds. Failure to stage within the time limit results in automatic red light for the delaying party.


BYE RUNS:

All competitors must take the tree and complete a full pass under their own power on a bye run.



SCALE POLICY:

All USP Racers will scale after every pass. Failure to scale during qualifying means the run will not count. Failure to scale during eliminations will result in disqualification and reinstatement of the losing competitor, providing they also scale and make minimum weight.


CLASS GUIDELINES

LETTERING / DECALS:

Limited to windows only, with the exception of one 12" x 36" sponsor decal. Front lower right of windshield must be cleared for class sponsor.


FIREWALL :
Must retain factory firewall. No Exceptions.

INTERIOR:

Dash, steering column and seats must be in stock locations. Aftermarket or street rod columns permitted. Door panels must be covered or painted. Stock type pedals in stock location are required. A full stock dashboard with instruments required (aftermarket instruments allowed).


SEAT LOCATION:

Two front bucket seats (racing seats OK), or full bench seat with upholstery is required. Back seat may be deleted if it interferes with roll cage.


CHASSIS / SUSPENSION:
Front Suspension:

Components must remain in stock locations. Direct bolt on A-arms are permitted. Tubular K-members that are a direct bolt on are permitted. Replacement front suspensions, like Alston, Fatman, TCI, AJE, and Smith Racecraft are allowed.


REAR SUSPENSION:

Suspension components must all remain in stock locations. Aftermarket control arms and springs allowed. Frame notching is allowed for tire clearance, but inner frame rail must be retained. Shocks may be moved inward for tire clearance only, but must retain factory angle. No coil over shocks permitted unless vehicle was originally equipped . Leaf springs may be moved inward for tire clearance purposes only. Weld in anti roll bars are legal.


DRIVE TRAIN:

AUTOMATIC TRANSMISSION: Automatic transmissions originally produced by an American auto manufacturer are permitted. Transmission to engine adapters are allowed. Trans-brake allowed.


MANUAL TRANSMISION: After market clutch assisted manual transmissions allowed. Clutch-automatics or planetary transmissions are NOT allowed. All shifts must be made manually without the aid of electric, hydraulic or pneumatic devices. Any manual transmission built by an automotive manufacturer with stock case and gears will race at same weight as an automatic transmission entry. See weight break section.


ENGINE:

Any production based engine may be used. Crossbreeding of an engine to a different make of body is acceptable, however the stock engine bay and firewall must be retained. There are no restrictions on internal engine modifications. No dry sump oiling systems allowed.


BLOCK:

Aftermarket cast iron or aluminum blocks are permitted using stock deck height measurements or lower. DISPLACEMENT LIMITS: 565 CI max for big blocks, 412 CI max for super and turbo charged small blocks, 434 CI max for nitrous small blocks.


ENGINE LOCATION:

Engine must be in stock location. Solid motor mounts and motor plates allowed. If cross breeding an engine, valve covers may not touch original factory firewall.


CYLINDER HEADS:

Two valves per cylinder maximum unless originally equipped with three or four valves per cylinder. The following are cylinder head restrictions (1) No splayed, symmetrical, or canted valve small block heads (unless it is a factory style replacement) (2) One spark plug per cylinder (3) All billet cylinder heads prohibited (4) No Pro Stock small block heads. (5) No Big blocks heads that are more than +/- 2-deg from stock. (6) No SB2, Yates, Neal, Big Chief, Pontiac, Olds, Big Duke, or any other symmetrical and non conventional style cylinder heads.


EXHAUST:
Mufflers required. Modification or removal of muffler internals is prohibited.

FUEL / FUEL SYSTEM:

Gasoline Only. No Alcohol or Nitro permitted. USP reserves the right to check gasoline at any time during competition. The addition of chemical additives intended to alter the makeup of gasoline for increased performance is strictly prohibited. During fuel check the competitor must identify the brand of gasoline being used. Failure to pass fuel check is grounds for disallowance of a run during competition and disqualification from the event during eliminations.


INDUCTION:

NITROUS OXIDE SYSTEM:

Limited to a multi stage plate system or a single fogger system. Two(2) Nitrous and Two(2) Gasoline fuel solenoids ONLY. Purge System for each stage permitted, but must exit outside engine compartment and not be directed towards any air inlet. Nitrous may not be used in conjunction with any turbo or supercharger. Nitrous electronic controllers are permitted.


SUPERCHARGER

Roots type superchargers up to 871 are permitted. Single centrifugal superchargers are permitted. Superchargers choices are limited and only certain units are legal (see weight breaks). Anything not listed in the supercharger groupings is not legal for Limited Street competition. Nitrous may not be used in conjunction with any superchgarger.


TURBOCHARGER:
1) Turbocharger must be of conventional impeller and housing design and type.
2) Single turbocharger is limited to a maximum size of 3.46 inches (88mm) inducer diameter at the point where the leading edge of the compressor wheel meets the inlet housing. Twin Turbo is limited to maximum size of 2.36 inches (60mm) inducer diameter at the point where the leading edge of the compressor wheel meets the inlet housing.
3) Maximum clearance allowed between impeller and inlet cover is .079 inches (2mm)
4) All air entering the turbocharger must pass through the turbocharger inlet.
5) Injection of any liquid, gas, or any other substance into the inlet or exhaust housing prohibited.
6) Compressor wheel contour must be a continuous contour from the inducer to the exducer (no "stepped" wheels).
7) Nitrous may NOT be used in conjunction with any turbo.

STEERING:
Rack and pinion allowed on all vehicles

STREET LEGAL REQUIREMENTS:

All entries are required to have working headlights and tail lights. Brake lights and turn signals are not required.


TIRES:

Maximum drive axle tires may be Mickey Thompson 30 x 12.50 or 28 x 12.50 ET Streets, 29.5 x 10.5 or 28 x 10.5 ET Drag. Also Hoosier 29 x 11.5 or 28 x 11.5 Quick Time Pro or 29 x 10.5 or 28 x 10.5 Drag Slicks will be allowed. Alternate smaller tires will be allowed.


Centrifugal Supercharger Weight Guide:
Group 1 Legal Superchargers: Vortech A, S, YS-Trim, ProChager D-1SC, D1
Small Block up to 365 CI: 2850 lbs
Small Block 366-440 CI: 2950 lbs
Big Block up to 510 CI: 3200 lbs

Group 2 Legal Superchargers: Vortech J-Trim, ProCharger D-1R, F-1, Pax Novi 2000
Small Block up 365 CI: 2950 lbs
Small Block 366-440 CI: 3050 lbs
Big Block up to 510 CI: 3300 lbs

Group 3 Legal Superchargers: Vortech X-Trim, ProCharger D-1X, D-2, F-1R
Small Block up to 365 CI 3050 lbs
Small Block 366-440 CI: 3100 lbs
Big Block up to 510 CI: 3350 lbs

Group 4 Legal Superchargers: Vortech XX-Trim, Z-Trim,
ProCharger D-2R, D-3C, D-3M, F-2, Paxton Novi 3000
Small Block up to 365 CI: 3100 lbs
Small Block 366-440 CI: 3200 lbs
Big Block up to 510 CI: 3450 lbs

LIMITED STREET WEIGHT GUIDE:

These are base weights please see add weight section at the bottom of weight guide. All weights are total including driver.


4-CYL SECTION:
Naturally Aspirated / 1900lbs
Nitrous Assisted / 2400lbs
Single Turbocharged up to 70.00mm / 2250lbs
Supercharged / 2250lbs

V-6 SECTION:
Naturally Aspirated / 2300lbs
Nitrous Assisted / 2950lbs
Single Turbo Assisted up to 80.00 mm / 3000lbs
Single Turbo Assisted 80.001-88.00mm / 3100lbs
Twin Turbo Assisted up to 60.00mm each / 3200lbs

SMALL BLOCK SECTION:
Small Block / Naturally Aspirated / up to 434CI / 2400lbs
Small Block / Nitrous / up to 434CI / 3000lbs
Small Block Roots Supercharged / up to 365CI / 2950lbs
Small Block Roots Supercharged / 366ci-412CI / 3100lbs
Small Block Single Turbocharged up to 76mm / up to 412CI / 2950lbs
Small Block Single Turbocharged up to 80mm / up to 412CI / 3100lbs
Small Block Single Turbocharged up to 88mm / up to 412CI / 3200lbs
Small Block Twin Turbocharged up to 60mm each / up to 412CI / 3200lbs

BIG BLOCK SECTION:
Big Block (up to 540CI) Naturally Aspirated / 2800lbs
Big Block (541-565CI) Naturally Aspirated / 2950lbs
Big Block Nitrous (up to 540CI) 3300lbs
Big Block Nitrous (541-565CI) 3400lbs
Big Block Roots Supercharged (up to 510CI) 3400lbs
Big Block (up to 510CI) Single Turbocharged up to 88mm / 3300lbs
Big Block (up to 510CI) Twin Turbocharged up to 60mm each / 3450lbs

ADD WEIGHT SECTION:

100 lbs. for the use of inter or after coolers on supercharged or turbocharged vehicles. (see super charger and turbocharger section for base weights) 50 lbs. for the use of aftermarket manual transmission.


CHEATING AND PENALTIES FOR CHEATING:

Cheating will result in mandatory expulsion from event, loss of any points earned at event and forfeiture of any winnings. Mandatory one race suspension with a $500 reinstatement fee. Any competitor protesting another must post a $100 protest fee that is non-refundable.


CONTINGENCY:
Only registered USP-Racing members are eligible for contingency benefits.

YEAR END POINTS STANDINGS:

2008 racers will be able to run their earned class numbers. Example: Aaron Walker L/S-1. 2009 racers will only be eligible for the points race if they are a registered USP-Racing member.


DECISION MAKING DURING RACE DAY:
Will be final and based solely on discretion of the race director.