Bleed Valve - TDDi

Bleed Valve - TDDi

Background

This mod can be done on 90PS/115PS TDDi Engines using the fixed Vane Turbo. It may be possible on the Variable vane turbo but that may require some ingenuity on your part!

This might work on TDCi 115/90 engines, you will have to check that the TDCi does not have the boost controlled by the PCM. If not the following procedure should be fine.

Equipment required

• Knife - Stanley type will do.
• Rubber tubing of 2.5mm inside diameter - a few inches will do.
• 2 valves (one inline, one T type) or a double outlet valve (which I used)

There are other things you can do to alter the characteristics of the turbo (such as overboost) but i will concentrate on upping the boost for now.

I will not accept any responsibility for damage to your engine/turbo!!!

You must remember that Ford set your car up to run for lots of miles within varying conditions/driving styles/maintenance levels. Increasing the amount of work that any part has to do may affect it or othe related components.

All I can say is that i have done about 3500 miles with this mod done to it and its okay! (86K miles on the clock)

What this mod will do

• Increase maximum boost pressure - Extra BHP + Torque.
• Reduce turbo lag.

How to do it

1, Make sure that your turbo is cold!!! even just the heat shield get very hot and burns hurt!

2, Locate the actuator, it should be exposed from the heat shield withy a single rubber tube running from the back (bulkhead side) of it.

3, There is a 'squeezy' clip holding this in place, I had to shuffle it round so that the 'squeezy' bit was at the top,

4, Squeeze the clip and slide it down the hose a little (you can do this with your fingers)

5, fit the inline valve here, set it to about half shut.

6, Add a short length of tube and add the second valve (closed) and fit a piece of tube to connect it to the actuator once more.

7, Test run. The car should be standard, but you should experience slightly better turbo performance, as in it gets to full boost sooner (less lag).

8, Open the T type valve slightly to allow some boost to escape.

9, Repeat 7 and 8 until happy.

If you prefer science to guesswork you might like to fit a boost guage. fit this on the Turbo side of the valves to get an accurate reading.

To get the best benefit of the inline valve and reducing the lag more, you should fit the inline valve as close to the compressor housing as possible. I fitted it further away because it was easier to fiddle with!

Although I have been refering to it as lag, it is not. what happens is that as your turbo approaches max pressure the wastegate begins to open, so it takes longer to get those last few psi's of boost. Restricting the flow to the actuator means that the pressure in the intake reaches the correct pressure before the wastegate opens, so you have full boost for longer.

You can experiment with both valves to see what suits you best. NEVER CLOSE THE INLINE VALVE FULLY as the turbo will have no limiter as to its speed so you could end up with all sorts of problems!!!

With regard to overboost...

If you 'T' in an empty volume, such as a small aerosol can after the valves (on the actuator side) you will get an overboost effect, the size of the volume = the amount of overboost. This is because the intake pressure will keep increasing while it fills the extra volume before the wastegate is able to open.

I will add some pics when i find them again!

Feel free to PT me, Rainbowcar, if you have any questions.

I did plenty of research and study on this so I should be able to answer your questions! lol.