I have been playing around with a mechanical way of reducing egt's. Simple and effective, non electronic bleed off valve that should give years of good service. I have been testing it for month's now and seems all is OK. It's really simple and cost efficient. The threoy is to bleed off boost so that the boost psi that is sent to the boost sensor is less the the actual boost being produced by the turbo. The computer reads boost pressure through the boost sensor and adds fuel accordingly. More boost, and the computer thinking there has been no change in boost, equals lower egt's.
A short shopping list:
- A boost controller (for the turbo to increase boost)
- An air ram speed controller (that can be adjusted and lockable)
- A few vacuum tee's and vacuum hose
- A one way vacuum check valve ( I don't think it was necessary but made one anyways because the 2lte has a throttle plate and under engine braking creates vacuum.)
- cheap fuel pressure/vacuum gauge good to 15psi.
The total for the materials for me was around $100.00.
I installed my aftermarket boost gauge on the boost sensor vacuum line before the factory check valve (not a real check valve just helps to stop fluttering to the boost sensor). After the factory check valve goes the bleed off valve wit a one way check valve. The vacuum line continues to the boost sensor and right before the boost sensor i put a tee to the aux boost gauge (princess auto had a low pressure psi gauge for cheap). Now I cold see actual turbo boost pressure and the boost pressure the computer thinks I have.
A benefit to this system is that it is progressive. At 2.5 psi it is almost equal between actual boost and what the computer thinks.
at 5 psi the computer thinks it's 4psi. At 10 psi the computer thinks it is 8 psi and at full boost of 15 psi the computer thinks it's 12 psi. The bleed off valve (air air ram speed controller) can be adjusted to almost anything you want. After the system was installed, I returned the aftermarket boost sensor to the boost vacuum line right before the boost sensor. It reads less boost then what is really being made but is all relevant because if there is a problem the boost will change alerting me. On the progressive scale I have done, I have seen a drop of about 150 degrees Fahrenheit in egts. This is not the golden answer to the 2lte's problems but it sure helps.
Take care.
A short shopping list:
- A boost controller (for the turbo to increase boost)
- An air ram speed controller (that can be adjusted and lockable)
- A few vacuum tee's and vacuum hose
- A one way vacuum check valve ( I don't think it was necessary but made one anyways because the 2lte has a throttle plate and under engine braking creates vacuum.)
- cheap fuel pressure/vacuum gauge good to 15psi.
The total for the materials for me was around $100.00.
I installed my aftermarket boost gauge on the boost sensor vacuum line before the factory check valve (not a real check valve just helps to stop fluttering to the boost sensor). After the factory check valve goes the bleed off valve wit a one way check valve. The vacuum line continues to the boost sensor and right before the boost sensor i put a tee to the aux boost gauge (princess auto had a low pressure psi gauge for cheap). Now I cold see actual turbo boost pressure and the boost pressure the computer thinks I have.
A benefit to this system is that it is progressive. At 2.5 psi it is almost equal between actual boost and what the computer thinks.
at 5 psi the computer thinks it's 4psi. At 10 psi the computer thinks it is 8 psi and at full boost of 15 psi the computer thinks it's 12 psi. The bleed off valve (air air ram speed controller) can be adjusted to almost anything you want. After the system was installed, I returned the aftermarket boost sensor to the boost vacuum line right before the boost sensor. It reads less boost then what is really being made but is all relevant because if there is a problem the boost will change alerting me. On the progressive scale I have done, I have seen a drop of about 150 degrees Fahrenheit in egts. This is not the golden answer to the 2lte's problems but it sure helps.
Take care.