TD42 Split-Pulse Exhaust Manifold. Constructed from SiMo Ductile iron.
Our TD42 Split-Pulse Exhaust Manifold fits all GQ/GU TD42 Engines (Silvertop or Blacktop). Retaining the low-mounted turbo position to avoid large changes in intake and exhaust pipework. The turbo mounting position has been pushed forward to remove the restrictive dogleg bend in the factory manifolds at cylinder 4.
It also allows more space for dump pipe variations, larger diameter dump pipes and removes the need to bring the dump pipe down at such an acute angle to clear the firewall and heater hoses. An External wastegate is easily able to be plumbed back into the dump pipe close to the turbo as well.
IMPORTANT NOTE: This manifold is not a direct factory replacement – The position of the turbo does not match the exact same position as a factory TD42 manifold. Factory and some aftermarket dump pipes will not just bolt on and be in the correct position when using this manifold. It is an upgrade and as such some modifications may need to be done to the dump pipe and intake pipework to make it fit some setups. If you have any questions regarding the fitment of the manifold please email or call us before purchasing this product.
A split pulse exhaust manifold will provide more drive energy to the turbine over conventional merge-type manifolds of an equal design. The larger thermal mass with thicker walls and more material around critical areas also provides better heat retention of the exhaust gas while it travels to the turbine.
The more heat that can be retained from the combustion event and well directed by the use of the split pulse design, the more energy that can be delivered to the turbine. For a given amount of fuel, this will equate to better efficiency, a faster-spooling turbocharger, and more power and torque on any given setup.
We have included the option to use a Turbosmart EWG 38mm External Wastegate that will bolt directly to the manifold while keeping the Split Pulse design in full function.
A blanking plate and gasket will be provided with the purchase of all manifolds at no extra charge for those who wish to retain the internal wastegate function of their existing turbocharger.
External wastegates provide a significant benefit to performance and efficiency and are a far more stable form of boost control on most engines with the ability to control both the pressure holding the wastegate shut, as well as the pressure pushing it open. Usually resolving the boost tapering off above peak torque as is apparent with most internally gated setups available on the market today.
A pressed stainless steel turbine inlet gasket and a choice of steel or Inconel 625 exhaust to turbo studs will be provided as per the order.
Both come with 316 Grade stainless steel washers and copper coated German made WURTH prevailing torque lock nuts.
An Inconel 625 stud kit for fixing the manifold to the head can be purchased separately here
Or, you can specify the Inconel stud mounting kit with the manifold as you add it to the cart.
Each manifold comes with the choice of a Raw cast finish. Or HPC Extreme Temp black performed right here in Brisbane by Thermal Edge Coating > http://www.thermaledgecoating.com.au/
If you prefer silver or other types of coatings please contact us prior to order for lead times on these.