Turbo To Manifold Pressure Drop

[Ralph Wiggum]

a HDI cooler, 580 x 220 x 100...

boost definately seems to start to fade when the motor is hot...

I pressure tested my intercooler piping on the weekend, and found no leaks!

so if my turbo is pushing constant pressure, and I have no leaks in my pipework, im thinking that I might have a leak in the intake manifold somewhere that gets worse after it gets hot...

Boost will drop off when hot as will timing. The cars are tuned this way too reduce stress on the motor

[FORDPSI]

How did you measure this? Did you do the actuator line first then the manifold after that? Or did you do have two gauges and did it at once?

[FAST-XR]

How did you measure this? Did you do the actuator line first then the manifold after that? Or did you do have two gauges and did it at once?

I measured them seperately.

I moved my boost gauge from the manifold to read from the actuator line

Boost will drop off when hot as will timing. The cars are tuned this way too reduce stress on the motor

how does boost get pulled out when the actuator has constant pressure?

[spoolxr6]

Where abouts on the actuator are you measuring, before the solonoid or after?

[FAST-XR]

Where abouts on the actuator are you measuring, before the solonoid or after?

between the turbo and the solenoid...

[Ralph Wiggum]

What exhaust/cat is on the car?

[FAST-XR]

100cpi 5" cat. stock exhaust with straight through 2.5" mufflers...

[spoolxr6]

Look if you have no leaks in the pipes the only thing that sits in line with the pipework is the intercooler so it's the only thing that could be a restriction and from previous experience it was that for me. The drop off in boost as the revs increase also highlights the intecoolers ineffeciancy as the turbos flow/load is increased.

[spoolxr6]

Think of it this way, if you had the pipe go straight from the turbo to the TB the pressure would be the same even if you had a leak on the pipe somewhere the pressure would be even accross all of it. So the only thing in its course at the moment is the cooler. Even if the BOV was leaking like EPIC mentioned the pressure on the turbo side would also be the same. So you are not chasing a leak you are looking for a restriction.

[Ralph Wiggum]

between the turbo and the solenoid...

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.

However, Spool is right, the cooler isnt flowing enough air too maintain the boost pressure.