
| Managing Director: | Dave Bennett |
| General Manager: | Nigel Hayes |
| Mfg. Projects Mgr: | Con Dimaras |
| Sales Supervisor: | Mark Connor |
From humble beginnings in the early 1960's "Dyno" Dave Bennett and his staff have built Perfectune YELLA TERRA into Australia's leading manufacturer of performance cylinder heads, roller rockers and associated engine parts. As a company Perfectune have always been committed to constant product improvement through motor sport involvement. From success in the early days of drag racing, to milestone performance advancements in alloy cylinder head and roller rocker designs proven over many years and millions of trouble free race kilometres in Australian Touring Car and Auscar racing.
CNC MACHINING AND MANUFACTURING SPECIALISTS FOR AUTOMOTIVE - INDUSTRIAL - AEROSPACE - COMPONENTS OR COMPLETE ASSEMBLIES
Complex components are our specialty. Perfectune Engineering is equipped with a wide range of ‘State of the Art’ computerised "CNC" Machining Centres and Lathes with 4, 5, 6,and 7 axis capability - over 70 machines in total. We produce components from tiny rollers up to large rectangular parts 1500mm in length x 500mm 500mm.
New Cylinder Heads
The success of Yella Terra on and off the race track has not been restricted to Australia. The company's totally unique roller rockers designs were an instant success when introduced in the USA in the early 1980's supported by world beating performances in US drag racing by Australia's own Graeme Cowin. Perfectune's experise in product design and advanced CNC manufacturing techniques have earned the company a reputation as an efficient and reliable source for a large range of other components required by the automotive and general industries. Contract machining is now a major activity in the Perfectune organisation with flexible CNC machining facilities supported by the most advanced inspection techniques, including a large capacity 3 axis coordinate measuring machine.
CNC

We can almost certainly produce components to your requirements, assemble, pack and ship them if required.
International companies rely on us to produce products and services for the world market.
We are renowned for quality products, produced with quality certification, on time by a dedicated team.
Prompt competitive quotes assured.
Roller Rockers

THE WORLD'S LARGEST RANGE OVER 130 MODELS
Roller Rockers for your performance demands and budget
STREET TERRA
Economically priced rocker set for popular applications features strong vacuum die cast arms designed for high performance street and budget race applications. The range makes a realistically priced and ultra reliable standard replacement and are strongest budget priced rockers available.
Street Terra rockers feature the same YELLA TERRA best quality hardware, for durability, low friction and reliability.
YELLA TERRA
The strongest aluminium rocker arms in the world, with deflection and bend tests proving their Aircraft grade extruded aluminium arms superior to rival aluminium and stainless steel arms. Available for a large range of applications, for use in high revving street engines and almost every conceivable race application. This superior arm is complemented by the strongest and best hardware in the business. Proven the strongest alloy rockers available.
Attention to detail ensures an unrivalled LIFETIME WARRANTY REGARDLESS OF USE.
HI TORQUE
The YELLA TERRA Hi Torque design improves low end and mid range power in applications where these characteristics are lacking. Port sizes remain small to improve gas velocity at low RPMs with valve sizes and combustion chamber shapes designed to further enhance response at low RPMs whilst improving fuel efficiency. Potential buyers may feel that the HI TORQUE heads are the bottom of the line and not for them. The feeling that if some head modification is good- then more - or a higher stage will be better - is not necessarily so - this can work against the ultimate use of the vehicle. This is particularly so with the smaller capacity Holden and Ford 6 and V8 engines. For example, the extremely successful "Commodore Cup" - Control Class use our Hi Torque Heads on 253 engines with excellent racing results. All YELLA TERRA Hi Torque heads are coloured BLACK for easy identification.
GAS PERFORMER
The increased popularity of LP Gas has naturally lead to demand for performance engines capable of utilising this economical fuel. In response to these demands YELLA TERRA have released the Gas Performer range designed to provide reliable performance using LP Gas or dual fuel. LP gas as a fuel does not contain any Tetra - Ethyl lead which has been used for decades to lubricate valve seats, valve guides and valves against excessive wear, as well as increase the octane rating of petrol. All Gas Performer heads feature Double Diamond oversize Tufftrided valves and diamond honed guides matched to hardened seat inserts to resist wear in the high temperature unleaded engine environment that LP Gas creates. Gas Performer heads are coloured BLUE for easy identification.
Exchange Heads

STREET PERFORMER
The original YELLA TERRA head that is the number one choice of street engine builders throughout Australia. Sometimes referred to as a "Stage 3" head all Street Performer models feature oversize Double Diamond valves combined with machine enhanced ports and combustion chambers. Upgraded valve springs are fitted to improve valve train reliability at higher RPMs. Performance improvements of between 15-30% can be expected on otherwise standard engines with improved fuel efficiency. Higher increases can be expected when fitted in conjunction with modified camshafts, carburation and exhaust systems. All Street Performer heads are coloured traditional YELLA TERRA YELLOW for easy identification.
ROAD RACER
The Road Racer range suits engine builders looking for extra road or race performance and feature double valve springs and chrome moly retainers capable of handling high lift camshafts at high RPM's. Every Road Racer head is machined to accept heavy duty screw in studs or the highly recommended YELLA TERRA Heavy Duty Race type bolt on shaft or pedestal rockers, except BATH 6000, machining is an extra cost option. Larger Double Diamond valves are used in conjunction with high flow port designs and redesigned high compression combustion chambers. Further performance gains are possible with detailed hand port finishing. All Road Racer heads are coloured RED for easy identification.
NEW CAST IRON
YELLA TERRA new cast iron heads are produced from, premium grade iron that is 15 to 20% harder than a standard cast iron head for high resistance to cracking and valve seat wear. Heads designed for use with LP Gas are fitted with hard nickel chrome heat and wear resistant exhaust valve seats. The port shapes, water jackets and combustion chambers have all been redesigned to provide at least 25% better airflow and improved cooling for reliable performance gains. The roller rockers pictured with the head are sold separately and highly recommended to fit with any YELLA TERRA new cast iron performance cylinder heads.
NEW ALLOY
YELLA TERRA new alloy castings are produced from AS601, 356-T6 heat treated aluminum that offers a weight saving of 50% over cast iron. All alloy heads are compatible with LP Gas and unleaded fuels. A variety of innovative port and combustion chamber designs are available to offer massive airflow gains over standard heads. Castings have been designed to allow additional custom porting for even greater performance improvements.
The roller rockers pictured with the head are sold separately and highly recommended to fit with any YELLA TERRA new alloy performance cylinder heads.
Flywheels

For safety reasons, cast iron flywheels are now required equipment in Group 'A', Auscar, Speedway and many racing classes.
Manufactured from a solid steel billet and fitted with a OEM quality ring gear, these steel flywheels are lighter than original cast iron units.
Available for Chevrolet, V8, Holden 6 and V8, Ford V8, C. and W. in various configurations, in steel, lightweight steel and aluminium fitted with cast iron clutch face insert.
Australia:
Phone International: +61 3 9555 5522
Fax International: +61 3 9555 4152