Modified Street Blown Rules


1.1 Front suspensions  can be fabricated but must bolt into stock location, fabricated tube control arms and K members permitted, stock front cross members may be scalloped for sump clearance. In Australian & American bodied vehicles , where front end unbolts, fabricated local front end permitted but must be of similar design to standard, i.e. Holden HQ-WB ,RS Camaro & Chevrolet Nova front end. Steering rack conversions permitted.

APSA would like to ensure that all front suspension components are built with safety as paramount in all cases.
ANDRA safety rules apply to all cars.

1.2 Firewall must remain in standard position. Notching for distributor or rocker cover clearance only is permitted. Flat firewalls are permitted but must be in standard location. Chassis rails in engine bays may be chambered to a cross section of 60mm x 60mm or an area equaling to this amount to allow exhaust clearance. All material removed from chassis rails must be replaced with the same thickness material or thicker. This may also be the case for cars needing to notch strut towers in engine bays for pipe clearance. Chassis rails must be in standard location. Inner guards must be retained but can be cut for pipe clearance.

1.3 Front struts may be replaced; aftermarket products must bolt up in the factory position.

1.4 Inner rear wheel tubs may be moved inwards, full tub replacement permitted. Chassis connectors are permitted.

1.5 Standard rear suspension points must be used, rear suspension mounts maybe reinforced or fabricated in standard size, shock absorber location can be moved, and leaf springs can be moved inwards.

1.6 Coil over shocks are permitted for tyre clearance.

1.7 Rear chassis rails may be notched for tyre clearance but not moved or rerouted. Inner chassis rail cannot be moved and must remain in factory position. Any metal cut away must be replaced with the same thickness material or thicker. Special permission may be given to existing cars with rails moved if standard points are retained and tyre is within the limits, but must be checked with APSA committee.

1.8 Four links and ladder bars are not permitted.

1.9 Adjustable tubular control arms may be used on rear ends but must retain factory fixed mounting points and suspension set up. Tramp rods, Slapper bars, Caltrac bars or any other similar devices may be used. Anti roll or sway bars permitted.

1.10 Fiberglass panels are restricted to guards, nose cone, bonnet, boot lids and bumpers.

1.11 Lexan /polycarbonate windows permitted all round as per ANDRA specifications.

1.12 Must have some style of dash, original dash board may be replaced by a fabricated dash.


2.1 Engine blocks

Small blocks cast iron or Alloy permitted, only with standard cam and standard pan rail, Factory alloy blocks permitted, eg LS1

Max deck heights

  • SBC 9.025
  • SBF 9.5
  • Chrys SB 9.5
  • Holden 8.9
  • LS-1 9.2
  • Mod motor Ford 9.0

Big Blocks cast iron or Alloy permitted, only with standard cam and pan rail

Max deck heights

  • BBC 10.2
  • BBF 10.32
  • Chrys BB 10.7
  • Any other combinations must be standard deck height.

2.2 Maximum head gasket thickness .150″

2.3 Dry sumps permitted.


3.1 Transmissions must be OEM type, No Lenco’s or aftermarket clutch less type
3.2 Lock up convertors are permitted
3.3 Dedenbear cases are permitted


4.1 tba


5.1 Maximum diameter 15”


6.1 Rear tyre maximum width 12.5″ as marked on side wall and in measurement
6.2 Rear tyre maximum height 29.5” as marked on side wall and in measurement
6.3 No “W” tyres permitted on max size

6.4 Front tyres minimum width 3.5”


7.1 Roots type superchargers are as per Pro Street Blown but are restricted to 10:71

7.2 Turbochargers are as per Pro Street Blown but are restricted to a maximum size of 94mm inducer diameter (tip-to-tip) for single turbochargers and 70mm inducer (tip-to-tip) for twin turbochargers at the point where the edge of the compressor wheel meets the inlet housing and must be of conventional impeller and housing design (non-clipped).

7.3 Single centrifugal superchargers are permitted with a maximum inlet hose diameter of 6.00in and maximum discharge hose diameter of 4.00in (e.g. Procharger F-3R-131).

7.4 Nitrous Oxide systems are restricted to two stages only. Fogger or plate systems permitted. If using direct port systems, a maximum of two nitrous solenoids, two fuel solenoids and two purge solenoids allowed. If using plate system, one nitrous, one fuel and one purge solenoid allowed. Nitrous controllers are permitted

7.5 Two Power Adder types allowed for 4Cyl, 12A & 13B, 6Cyl and 20B Engines only


8.1 Any ANDRA approved fuel permitted except nitro “see fuel list here

9. MINIMUM WEIGHTS  [ including driver ]

4Cyl & Rotary (Max13B) 2400Lb
6Cyl & 20B 2600Lb

V8 Engines:

BB Nos 2800Lb
SB Nos 2600Lb

BB Roots Blown 3000Lb
SB Roots Blown 2800Lb

BB Twin Turbo & Pro Charger 3200Lb
SB Twin Turbo & Pro Charger 3000Lb
(Single Turbo Deduct 150Lb)


10.1 All vehicles must comply with current ADRL & ANDRA safety regulations relative to performance of vehicle.



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