How to tune a Land Rover TDi engine for more power is something we all wonder at some point or another and we have a simple solution that will not only increase performance, it will also result in better fuel economy!
Tuning your TDi: The easy way….
Almost all Land Rover TDi engines are fitted with the Bosch VE rotary injection pump which is common to many engines from the 1990’s.
There are a couple of simple modifications that can be made to the Bosch VE pump to improve performance and even fuel economy. Both modifications are relatively simple to do with minimal tools required.
⦁ Boost Pin
A boost pin replaces the standard guide pin inside the Bosch VE LDA housing (also known as a AFC housing).
The guide pin has a profile machined into it which controls fuel delivery under boost pressure, as the boost pressure rises the guide pin is pushed downwards and the maximum fuel delivery available is increased. The boost pin is designed to allow you access to the full travel available inside the injection pump, so you can reach maximum fueling. This means you can keep your off boost or low boost fueling low to reduce smoke levels while still getting the fuel you require at high boost pressures.
It is a straightforward product to install, you just remove the four screws holding the top on the LDA housing and remove the LDA housing top. This then allows you to remove the original guide pin complete with its rubber diaphragm. You then undo the nut on the top of the guide pin and swap all the diaphragm assembly over to the new boost pin with the nut and tighten. The boost pin is then installed into the LDA housing just as the guide pin was, making sure the machined profile is facing the front of the engine.
⦁ Dynamic Timing Spacer Kit
As engine speeds increase the fuel has less time to burn. The Bosch VE injection pump already compensates for this by injecting the fuel earlier via the dynamic timing advance mechanism. The Dynamic Timing Advance Spacer Kit allows the timing piston which controls the dynamic timing advance mechanism to travel further which in turn allows the fuel to be injected earlier than the standard injection pump can allow. This is important because if we turn up the fuel delivery rate of the pump we increase the length of the injection event to increase the amount of fuel delivered. This longer injection event requires the timing to be advanced further to ensure the fuel has enough time to burn completely without smoke and optimise the bang per £ of diesel. This makes the engine more responsive and helps it to burn cleaner often reducing Exhaust Gas Temperatures.
The install of the spacer kit is straightforward like the boost pin, but fiddly due to tight access. Here is an easy to follow guide on installing a Dynamic Timing Spacer Kit:
How To Install Dynamic Timing Spacer Kit
First you use a torx key to remove the timing piston cover plate, ensuring not to drop any of the small calibration shims or springs inside the cover plate.
Next you replace the original Bosch O ring with the new genuine Bosch O ring supplied in the kit.
Now you can pre-assemble the timing piston cover plate ready to go back on the injection pump.
First you install the other genuine Bosch O ring into the spacer plate supplied with the kit. Then you put the supplied Allen cap head bolts into the timing piston cover plate with and put the spacer on the cover plate with the Bosch O ring against the cover plate.
Next you place the shim supplied with the kit in the bottom of the cover plate with the original calibration shims on top. Then you install the springs on top of the calibration shims (earlier injection pumps only have one spring) to have a combination like the one displayed below.
Finally, the timing piston cover plate is ready to go back on the injection pump and the install is complete! If you would like to increase the performance of your TDi, you can purchase a Dynamic timing kit or boost pin from Stegs Supplies, recommended by 4Mud!