Turbo To Manifold Pressure Drop

[FAST-XR]

I was after an indication of the hotside pressure, which is constant.

I might hook up the boost gauge to the line between the actuator and solenoid to add another peice to the puzzle. what pressure reading should I expect to see in this line?

[spoolxr6]

If you are measuring between the turbo and the solenoid your not getting a true picture of the boost pressure being supplied too the actuator. If the car is tuned too pull boost out up high you would see this when plumber between the solenoid and actuator.

He is not trying to measure the boost going to the actuator. The actuator will always require about 5psi to open (if standard) and the solonoid will stay shut in order to keep the boost rising until the desired pressure is reached and then it opens. If the boost is pulled back in the RPM you will also see this on the line before the solonoid because ultimately this is manifold pressure before all the restrictions. So if the solonoid is telling the actuator to run 10 psi then the pressure at the comp housing of the turbo should also be 10 psi, which is where the boost solonoid picks up its feed from.

[Ralph Wiggum]

I was after an indication of the hotside pressure, which is constant.I might hook up the boost gauge to the line between the actuator and solenoid to add another peice to the puzzle. what pressure reading should I expect to see in this line?

Nothing, Until the boost control system begins too work then as per Below You will see wastegate pressure (5.8 ish psi if stock) and then boost pressure should start too decrease.

He is not trying to measure the boost going to the actuator. The actuator will always require about 5psi to open (if standard) and the solonoid will stay shut in order to keep the boost rising until the desired pressure is reached and then it opens. If the boost is pulled back in the RPM you will also see this on the line before the solonoid because ultimately this is manifold pressure before all the restrictions. So if the solonoid is telling the actuator to run 10 psi then the pressure at the comp housing of the turbo should also be 10 psi, which is where the boost solonoid picks up its feed from.

You are quite right, expect for any pressure drop across the solenoid. The OP wanted too know how too test for constant pressure too the actuator, testing between the solenoid and actuator will do this.

At the end of the day your right about the cooler. As much as we would all like 0 pressure drop across a cooler, craming a huge amount of hot air @ pressure through a cooler (which is designed too expose as much surface area too the charge air as possible) is going too cause friction and pressure loss.

Personally i think with the OP's current setup he's chasing rainbows and the solution will be a more effcient cooler.

[spoolxr6]

As Hiddeous said above and I will reiterate again, it's probably in the core mate. Try a Plazmaman or Process West cooler and you will see the difference. At least you have now done some testing and you will have something to back it up with. The only thing is you will need a retune because you will find you will gain the boost back again as I did. Also heat soak cycles will be far more efficient as I found.

[FAST-XR]

thanks guys

at WOT, should manifold pressure be almost the same as intercooler outlet pressure?

if pressure falls away after the cooler in the same way that it falls away in the manifold, then its probably safe to say that the cooler is a POS

would a leak at the manifold leak have much of an effect on the reading at the intercooler outlet?

[Ralph Wiggum]

thanks guys

at WOT, should manifold pressure be almost the same as intercooler outlet pressure?

Yes

if pressure falls away after the cooler in the same way that it falls away in the manifold, then its probably safe to say that the cooler is a POS

Baring a leaking Bov or other connection after the cooler then Yes

would a leak at the manifold leak have much of an effect on the reading at the intercooler outlet?

Yes