3: Mitsubishi TD05 Series
We are all familiar with Mitsubishi’s Evolution line-up with its decent factory power output and lightning-fast acceleration. Respectable power levels have been seen from 4G63-powered Evo IV to IX on factory turbos, but which one is the best of them all? The turbos have improved with each model, making the TD05HR-16G6C-10.5T from the Evo IX the best option in terms of overall power and response. All Mitsubishi turbos from IV to IX are a twin-scroll design, to assist the fast response. The turbine wheel is made from a steel alloy called Inconel, and the compressor wheel is made from aluminium, which aids boost response due to its lightweight construction. The inclusion of the letter ‘R’ in the TD05HR-16G6C-10.5T means the turbo spins in an anti-clockwise direction, hence the need to include it in the part number. The big brother to the TD05HR is the TD05HRA, which features a titanium aluminide alloy turbine wheel. These can be found in the Evo IX RS, and from factory they come on boost at around 500rpm because of the lower inertia. With the use of E85, these factory turbos have been seen to support over 300kW at the wheels on 25psi of boost.
This is a very common upgrade on Evo IV–VIII models, and providing you have a tunable ECU, you’re set for serious midrange and top-end gains. If you own an Evo IV, you will need to purchase an Evo V ECU if you want to take it in for a re-flash. You will need a flange specific to this turbo if you decide to install it onto something else. The flange of the EJ20T-series TD05 turbo is different, so sorry, this won’t bolt up to your WRX.
The largest of the three, the TD05HR has the biggest compressor housing. Bolt this up to any Mitsubishi Evo from IV–VIII, and you will see very good gains throughout the powerband