TURBO MANIFOLD TIPS
When purchasing an off-the-shelf turbo manifold be sure to buy one that is of good quality. Many of the cheap and low-quality manifolds that have flooded the market are worse than the stock item in terms of reliability and power output, often fooling people with their shiny good looks. If you do buy one of the common, cheap inferior manifolds, ensure you have it checked over by a fabricator before it’s installed. Often the manifold-to-block flanges are warped straight out of the box, which can be a huge hassle, as the manifold studs often get pulled out due to the flex. Another common problem with these manifolds is cracking. Inferior welding quality and wall thickness, the weight of the turbo and wastegate are all enough to make the welds crack under high-heat situations. We’d recommend getting braces welded in-between the turbo flange and the manifold, and the wastegate flange and the manifold, which should ensure your flange welds won’t crack if you do choose to purchase one of these manifolds. We’d also recommend ensuring the downpipe is well supported, and a flexi-joint is used in conjunction with the aforementioned braces.
Another thing to check with these manifolds is the port diameters. Quite often the ports on the manifolds are different to that of the head. A good way to check this is by purchasing a good-quality OEM manifold gasket and comparing the port holes in the gasket to the manifold ports. Do not trust the gasket that is supplied with the manifold, as these are often made of a lower-quality material, and the ports will be the same as the manifold’s ports. Welding ‘dags’ have also been known to break away under high-heat situations, make their way through the manifold and into the turbine housing on the turbo, causing costly damage.