Page 179

Part No.

Approved Motown Block Description


9.025" Deck/3.990" Bore


9.025" Deck/4.000" Bore


9.025" Deck/4.115" Bore


9.025" Deck/4.125" Bore


(g) (h) (i)

(j) (k)

(l) (m)

(n) (o) (p) (q) T11-16-10 (a) (b) (c)

Production cylinder heads will be those that retain the same number of valves and retain OEM valve stem angle specifications in relation to the cylinder head face, number of spark plugs, number and location of ports and be interchangeable with the original OEM cylinder heads, as well as retain the original method of cooling. Cylinder heads may be machined but material may not be added. Cylinder heads may only be fitted to blocks of the same block deck height that the heads came from on production engine. V8 engines to be a maximum of two valves per cylinder. Crankshaft and Camshaft(s) may be substituted. Other engine modifications include modifications and substitution of engine components except the following are not permitted: (i) variable camshaft timing (V8's only), (ii) ceramic or carbon components, (iii) pistons of any other material other than monolithic aluminium, (iv) threaded fasteners of any material other than steel, (v) flywheels of any material other than steel or aluminium, (vi) Titanium components are limited to valve spring retainers only, effective 01/10/2010. NOTE: Ceramic and carbon components permitted in rotary engines. Maximum compression ratio 11:1 Owners/drivers of vehicles must make individual arrangements with qualified SNZ officials to measure engine cubic capacity and affix engine seals to block and sump in a prominent position. NO SEAL, NO RACE. Engine reconditioning certificates not accepted. Any engine inspected and found to contravene the rules will be declared an illegal engine. Refer Section G11-3 Technical Exclusions. The fuel delivery system to the carburettor may be modified, however the engine must still be fuelled via the carburettor which may be altered for methanol, but must still function as a normally aspirated carburettor. Any form of port or base injection, or the like is not permitted. No fuel injection systems allowed. Two return springs must be fitted to carburettors. The exhaust must exit behind the bulkhead, facing the rear and down. Battery Battery cut-out switch and engine cut-out switch to be fitted, and painted in a contrasting colour within easy reach of driver, at least 300mm from the fuel tap. Battery must be in a fully covered alloy, steel case securely mounted with a removable lid suitably insulated with foam rubber and protected from impact. Self starters must be in working order at all times.



2010 NZ Speedway Rule Book  

2010 NZ Speedway Rule Book