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NORTHLAND SPEEDWAY CHAMPS - BOARD OF CONTROL

STD STOCK - RULES

 

SPECIFICATIONS:

a  Only modifications specially mentioned in this chapter are approved - no other modifications are allowed.

b  All rules are to be read in conjunction with the Stockcar Specifications.

 

Section T12-1

c  Any roles herein shall over-ride those laid out in the SNZ Inc rule book, on corresponding specifications.

d  Restrictor plate to be SNZ approved 2001 version. Restrictor plate to be available from the clubs only and must be used at all times.

e  OEM means "Original Equipment Manufacture". In any vehicles that require OEM parts, their components must retain their original identification marks.

 

T12-2-2 ENGINE:

As per Stockcar Specifications but with the following limitations.

a  Engines must be stock standard externally, except as expressly permitted in these rules.

b  Both me cylinder head and me engine block must be from the same OEM manufacturer and must fit together in their OEM form: Ford to Ford, Chev to Chev, Holden to Holden.

c  The engine must be fitted with an inlet manifold that is standard for the engine being used, except as expressly permitted in T12-2-3.

d  Upon application to the Directors, inlet manifold package variations may be approved, provided that:

(i) The manifold is of the same generic manufacture as the original engine being used, and

(ii) The inlet manifold fits to the cylinder head in its OEM form, with no material added or removed from either the manifold or cylinder head.

e  Spacers between cylinder head and inlet manifold, and cylinder head and exhaust manifold, are not permitted.

f  Engine to have maximum of two valves per cylinder.

g  No controlled vacuum leaks are permitted except OEM crankcase ventilation.

h  Engine sump may be modified to increase oil capacity. Engine sump may be modified so as to provide an engine mounting system. Engine dry sump systems are not permitted.

i  Water pump and oil filter must be fitted in OEM position. Fuel pump, rocker     covers, air cleaner and radiator fan may be after market type.

j  Needle or roller type rockers are not permitted unless Standard OEM part of engine being used e.g.: Buick, EA Falcon and Nissan Maxima.

k  All over head cam engines must retain OEM hydraulic valve lash adjusters and rockers, used in OEM form.

i  Maximum inlet and Exhaust valve lift: 0.500".

m  Any engine inspected and found to contravene the rules will be declared an illegal engine.

Refer Section 10-3 Technical Exclusions.

Engines do not need to be sealed

T12-2-3 INLET MANIFOLD:

(a) Four- barrel inlet manifolds are not permitted,

(b) This cause applies to an engine originally fitted with a carburetor manifold:

1. The original V6 or V8 Carburetor must be OEM for die engine being used.

2. The OEM manifold may' be reduced in height only.

3. No other material of any kind may be added or removed from the interior or exterior of OEM manifold Except:

(i) The OEM manifold may have a one-piece acceptor plate 25mm maximum thickness welded or bolted to the inlet manifold.

(ii) The said acceptor plate hole must be square edged.

(iii) Where no OEM two-barrel carburetor manifold may have inlet manifold material removed from directly below the restrictor plate hole.

4. The approved restrictor plate must be fitted above the said acceptor plate if fitted.

5. One adapter plate 35mm maximum height may be fitted if required above the Restrictor plate and below the carburetor.

6. The inlet tract of the carburetor - adapter plate- restrictor plate must be in vertical plane.

(c) This cause applies to Flat 4, Flat 6, V6 and V8 engines originally fitted OEM with EFI multi-point injection manifolds;

1. The inlet manifold must be OEM for the engine being used, ie. no Ford 221 engines use a multi-point EFI manifold.

2. The OEM manifold may be reduced in height only.

3. The inlet throttle body assembly must be removed; inlet manifold must be totally sealed off at throttle body area

4. No other material of any kind may be added or removed from the interior or exterior of the OEM manifold, except that:

(i) The OEM manifold may have a one-piece acceptor plate 25mm maximum thickness welded or bolted to the inlet manifold,

(ii) The said acceptor plate hole must be square edged.

5. The approved restrictor plate must be fitted above the acceptor plate if fitted.

6. One adapter plate 35mm maximum height may be fitted if required, above the Restrictor plate and below the carburetor.

7. The inlet tract of the carburetor - adapter plate - restrictor plate- acceptor plate must be in one vertical plane.

8. The base face edge of me carburetor must be no more than 130mm from the top of the nearest inlet port- Except flat 6 engine has no height restriction but must comply with clauses 1-7 above STANDARD STOCKCAR RULES

(d)  This clause applies to In-line 4 & 6 cylinder engines.

1  The OEM manifold that is standard for the engine must be used.
2.  No material of any kind may be added or removed from the interior or exterior of the OEM manifold. Except that material may be removed from directly below restrictor plate hole.
3  Where a carburetor type manifold or central throttle body injection manifold is used that is not fitted with the original carburetor, an adaptor plate must be used.

4  This, one only adaptor plate, must not exceed 35mm in height including gaskets and restrictor plate.


5  The inlet tract of the carburettor - adapter plats - restrictor plate must be in one vertical plane.

 

(e)  This clause applies to in-line 6-cylinder OEM multi-point EFI manifold.

The EFI throttle body must be removed. A right angle adapter assembly with 60mm radius and a downdraft carburettor must be used. The base face edge of the carburettor must be no more than 100mm from the top of the inlet port. This adaptor measurement must include the thickness of the restrictor plate.

 

T12-2-4 Exhaust:

(a) Only a standard cast iron exhaust manifold must be used in its OEM form, however the exhaust manifold may be fitted upside down.
Standard exhaust manifold may not be of two front (or rear) halves. No extractors permitted.

(b) Mufflers are free however noise levels must comply with SNZ or local requirements. NOTE: use of after market mufflers may be subject to change.

 

T12-2-5 Carburettor:

(a) The carburettor must be of down draft design.
(b) Plastic fuel pump and plastic fuel line fittings and plastic pump bases are not permitted.

 

T12-2-6 Restrictor Plate:

(a)    A 300 cfm Restrictor plate must be fitted between the inlet manifold and the carburetor base or between inlet manifold and adapter plate.
(b) The internal hole of the restrictor plate must not be modified in any way. The restrictor plate must not be modified in any way.

 

T12-2-7 Adapter Plate, Acceptor Plate:

(a) The adaptor plate must be detachable from both manifold and carburetor.
 (b) Any permitted adapter plate must be non-porous and fitted with conventional gaskets.
 (c) The acceptor plate, if permitted, must be non-porous.

 (d) The intake tract of the adapter plate must be in one vertical plane.

 

T12-2-8 Ignition:

(a) No twin point distributors permitted. No after market Distributors permitted. Luminition is not permitted.

(b) Only original OEM electronic ignition distributors are permitted. Where a distributor is fitted, it must remain in original OEM ignition position in block or head, however where an engine has no ignition distributor fitted in its OEM form, the position of an OEM distributor is free.

(c) OEM microprocessors are permitted to control ignition only.

(d) OEM crankshaft sensors camshaft sensors and engine control units in their original OEM form are permitted to control ignition systems only.

(e) All sensors and control units must be standard OEM for the engine being used. No after market control units are permitted.


 

 

T12-2-9 Transmission

(a) Only standard OEM clutches and pressure plates are to be used.

(b) Flex plates may be changed to steel flywheels. Flex plate may be altered to accept standard OEM clutch assembly.

(c) No aluminum components are permitted. Hydraulic throw out bearings may be used.

(d) No quick-change gearboxes are permitted eg: standard gearboxes only, however may be shortened.

(e) A 40mm inspection hole in clutch bell-housing must be available. Position of inspection hole to be in line with clutch plate, in a position above the 50 and readily accessible.

(f) Quick-change or open tube type differentials are not permitted. Standard differentials may be offset.

 

T12-2-10 Steering Box:

Steering system optional.

 

T12-2-11 Shock Absorbers:

(a) OEM replacement shock absorbers must be used.

(b) Internally adjustable and externally adjustable shock absorbers are not permitted.

(c) Shock absorber must be removable for inspection.

(d) Original brand names and part numbers must be visible, if no brand name or numbers are visible the shock absorber is illegal.

(e) No rose joints on shocks shafts are permitted, however cast iron or steel OEM tie rod ends or tractor links 5/8 minimum size are permitted.

 

T12-2-12 Springs:

(a) Coil springs are permitted however coil-over spring assembly kits must be either cast iron, steel or brass.

(b)    No after market torsion bar systems are permitted.

 

T12-2-13 SUSPENSION:

(a) Suspension Joints: OEM joints, fixed pivot and bush joints are permitted. Only cast iron or steel tractor links 5/8 minimum size and rod ends are permitted.

(b) Rear suspension 5th coil type torque arm systems are not permitted.

Un-sprung and sliding torque systems are possible.

 

T12-2-14 STEERING:

Steering Joints: Cast iron or steel only.
OEM tie rod ends, tractor links 5/8 minimum size and rod ends are permitted.

 

T12-2-15 BRAKES:

(a) OEM brake parts must be fitted however mixing and matching is permitted.

(b) No adjustable hydraulic or mechanical brake bias systems are permitted.

(c) Only one brake master cylinder is permitted.

T1 2-2-16 TYRES:

(a) Standard road tyres must be used. All grooves must not exceed 1 Omm in width or depth.

(b) Racing type tyres, slick retreads are not permitted.

(c) Hand grooving to original tread pattern of tyres is permitted, 1 Omm maximum groove width. Added grooves are not permitted.

 

T12-2- 17 ENFORCEMENT OF SPECIFICATIONS:

(a) The use of any parts that may be considered non-standard or performance equipment must be submitted to SNZ for clarification.

(b) ALL Vehicles are subject to inspection by the head vehicle checker, who has the right to adjudicate on these specifications

 

 

 

 

Photos

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Entry Form

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Contacts:

President; Ken Crisp

Secretary; Debbie Beadle-Taylor 09-4012651

email beadletaylor@xtra.co.nz

Treasurer: Anita Sloot 021 782634

 

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