Thread: TD5 increase boost, what am I doing wrong!!

Depends what kind of drive you went on... Big hill? Hard climb? Bit of a drive up the road might not be enough to pass the previous waste gate setting.

I would say you really need a boost gauge to do it properly.

Without a guage it's very dangerous to adjust boost on any turbo engine, Just did mine but I have Gauge. Good luck!

Mmmm, dodgy territory.. As said before, boost gauge needed, or things might break. Not exactly sure how the Td5 deals with increased boost... Older engines with mechanical pumps had a pipe from the inlet manifold (after turbo) going to a diaphragm affair on top of the fuel pump.. The more the boost, the more the fuel, the more the go! The Td5 is electronically controlled by the ECU and might be preset.. so increasing the boost might do nothing??!! Tombie would be them an to ask. Buy a boost gauge and an EGT gauge before going too much further, and wind that waist gate back to where it should be!!!

Winding out the boost on the Td5 is pretty safe.
You should have marked the original position, and wind it out one turn at a time.
Then take it to a hill or a good flat section and go WOT.
When you start over-boosting (22psi) under load, i.e going into limp mode then you wind it back a quarter of a turn and you're done.

looks like we all agree, I just have to take it for a good flogging, I did wind it back to about where it originally was, so I can start over again, has anyone tried by-passing the boost modulator that the ECU uses to control boost?

Yes I run mine without the boost modulator, I've set it of the nanocom. It goes heaps better without it as it would always drive intermittently and sometimes cut fuel even though it wasn't anywhere near high boost levels.

Bronson

This is a common misunderstanding of the boost modulator function.

It's effect is also hard to see in real time...

The modulator improves performance in std trim (not VNT) by producing stable boost (no bleed at lower boost levels).

A faulty unit will cause problems as will a sticky waste gate.


As for over boosting... The TD5 will protect itself

Tombie x2

My understanding from reading and looking is that the modulator is like an electronic Dawes valve in that it stays closed until the boost target is reached then opens, thus giving BETTER performance on light to medium boost as the wastegate diaphragm gets no pressure so doesn't open a little with a few PSI boost.

Regards Philip A