Gasflowed / Big Valve Cylinder Heads for your Motor Car, SUV, Truck / Bakkie & Bike | Petrol & Diesel

The Gas Flowed Cylinder head

In the early eighties, modified or gasflowed / big valve cylinder heads were only ever found on racing cars. Today gasflowed / big valve cylinder heads have become very popular, given the current fuel pricing and huge gap in price between the top and middle of the range models, to enhance the power output of almost any modern vehicle. SAC Engineering has all the latest equipment and technical expertise to develop and gas flow cylinder heads for even the most recently launched petrol and diesel models. Contact us about cylinder head replacement, refurbishment or conversions.


Why does one Gas Flow a Cylinder Head?

Simply because this is what enhances the power. In order to maximise the explosion within the combustion chamber area of the cylinder head, we need to let as much as possible air / fuel mixture into the chamber. This mixture enters the chamber through the inlet port and is controlled by the inlet valve. Once this mixture is in place and gets ignited by a properly timed spark, the piston is forced downwards. The bigger the explosion, the more the downward force and the result is “More Power”. After the combustion stroke has taken place, the burnt gas exits the chamber past the exhaust valve and through the exhaust port into the exhaust system. This entire process is enhanced when the cylinder head has been gas-flowed.

Engineering Services – Cylinder Heads –

  • Gasflowed heads for most Petrol and Diesel vehicles
  • Full reconditioning of all heads
  • Flowbench developed heads
  • Full race heads
  • Big valve head conversions
  • Solid lifter head conversions
  • Motorcycle heads
  • Lineboring
  • Pressure testing
  • Aluminium and Cast iron welding

How do we do it?

Without going into great detail for obvious reasons, we use a flowbench on which we are able to measure port flow before and after the head has been flowed. In most cases we are able to increase the flow through a port by roughly 20%. This is achieved by carefully removing sharp edges and rounding acute corners, concentrating usually at the roof of the port where the highest flow activity takes place. We remove as little material as possible to ensure a lower overall port volume. Depending on the requirement, in most cases we tend to go for high flowing, small, high velocity port, which produce good top end power with virtually no bottom end loss. A great deal of time is spent on the valves and valve seats, where we gain good air flow with small valve openings. The combustion chamber as well as the exhaust ports are also changed considerably to promote more complete combustion.

A few of the Benefits of Gasflowed Cylinder Heads

  • Optimum power & torque
  • Lower Maintenance costs
  • No visual change in the engine bay
  • No risk of overheating
  • More Power and Torque (Especially when towing)
  • Excellent value for money
  • Improved fuel consumption
  • Fewer Gear changes
  • Improved fuel consumption
  • Quicker throttle response
  • Cleaner burning engine
  • Reliable performance
  • Flowbench developed
  • 6 months / 20 000km Warranty

Bolt on exhausts

Gone are the days that you take your half a million-rand Bakkie to a corner exhaust shop for a cheap free flow exhaust. It’s fair to say that the bolt-on free flow exhausts of today at SAC have been revolutionized and are becoming more and more popular amongst the enthusiasts. It is no longer just a poorly welded and routed exhaust that rattles and knocks over every bump, it is a properly engineered, big bore, mandrill bent stainless steel-low restriction exhaust system.  It is manufactured in such a way to be a bolt-on fitment in a workshop with very little effort to ensure perfection. Seeing the exhaust system in its raw form, packed and laying on a shelf – it is clear to see that this is an export quality product that will be installed on your vehicle, and it will compliment without any doubt – the performance enhancement plug and play kit and or upgraded intercooler system in many ways – most of all the sound and power will be much improved.  The bolt-on exhaust system is routed along the exact same rout under your vehicle and hangs with similar brackets on the standard rubbers.  The heat protection that has been provided by the manufacturer under your vehicle to protect the undercarriage is still effective and useful with the fitment of these bolt-on exhaust systems. So, if you want the ultimate Bakkie performance enhancement package speak to our sales and service advisors about a bolt-on exhaust system. Contact us today for your free quotation.