Hey man that was so cool and straight forward. I'm a beginner I bought an eBay wastgate and turbo but turbo doesn't have a vacuum port , where do I get my vacuum source for the bottom port on my wastgate ? Please help my vehicle doesn't come with a turbo.
I'm putting a rear mount turbo on my 2007 isuzu i290 truck but I need helpful tips on external wastgate vacuum source my turbo doesn't have a vacuum port.
You're gonna have pressure on the wastegate piston pushing too from exhaust pressure, so if its showing 10psi on the gate line alone to crack it... the actual vent pressure in the exhaust should be lower in operation. The delta would somewhere in the range of 1.5-3x more exhaust pressure to compressor side pressure. Assuming the turbo setup in the vid is 2x delta, then i would guess like 5psi operating pressure in the manifold. Its not exactly this way since diaphragm diameter vs wastegate piston diameter will change the dynamic, but worth pointing out. In this situation, at absolute most, if the turbine side is at max efficiency(1:1 delta on the manifolds, which basically never happens), then cracking the wastegate piston at 10psi means you can only make a max of 10psi in the intake side. The spring pressure is a situation where you don't even have a reference line hooked to the wastegate, in which case he said it was a 16psi spring, which would crack the piston side at 16psi exhaust manifold pressure. This would equate to like 8psi intake manifold side, with a 2:1 delta pressure across the turbo.
Right. Back pressure plays a huge part in actual pressure to open the piston. On a car with higher back pressure it’s going to lower the boost pressure to open the gate on a top vented setup. This was done on a 67mm 1.25ar turbo on a 2.5L engine. So there really isn’t much back pressure (or boost until about 4th gear for that matter) but yeah, you’re correct. This was more or less to show an easy way to get an idea of what spring you have in your gate. Most of the time this works well for getting into the ballpark. Unless you’re setup has excessive back pressure. But that’s what back pressure sensors and data logging are for if you want to get more precise.
An air compressor adds compressed air... He introduced compressed air through the regulator into the wastegate to actuate the valve to stimulate exhaust pressure on the valve in a turbo car.
Don't you have to take into account the pressure on the face of the valve? I mean what you did isn't wrong, but pressure on the valve could lower the springs effective pressure and the actual hotside pressure it takes for the valve to crack open?? I am learning, just asking, not trying to berate you.
The spring pressure of the wastegate determines what boost pressure (intake charge pressure) that the wastegate opens to hold/limit the boost. In this case, the turbo will always hit a peak of 12 psi. You can add a boost controller to raise it above that 12 psi, but you can't lower peak boost below 12 psi.
Wrong. The point or pressure where the valve first moves in you test is not the boost pressure you will get. It will be at least 2 psi lower due to exhaust manifold pressure making it open at a lower inlet manifold pressure.
Appreciate it man.. building my 6.0 monte carlo, been trying to figure this out 👍
I realize this is old but thanks for this.
Great video! Thank you!
Great tip man, I definitely bought a used wastegate and have no idea what the spring is set for lol
Same here!!
Hey man that was so cool and straight forward. I'm a beginner I bought an eBay wastgate and turbo but turbo doesn't have a vacuum port , where do I get my vacuum source for the bottom port on my wastgate ? Please help my vehicle doesn't come with a turbo.
nice job
I'm putting a rear mount turbo on my 2007 isuzu i290 truck but I need helpful tips on external wastgate vacuum source my turbo doesn't have a vacuum port.
You're gonna have pressure on the wastegate piston pushing too from exhaust pressure, so if its showing 10psi on the gate line alone to crack it... the actual vent pressure in the exhaust should be lower in operation. The delta would somewhere in the range of 1.5-3x more exhaust pressure to compressor side pressure. Assuming the turbo setup in the vid is 2x delta, then i would guess like 5psi operating pressure in the manifold. Its not exactly this way since diaphragm diameter vs wastegate piston diameter will change the dynamic, but worth pointing out.
In this situation, at absolute most, if the turbine side is at max efficiency(1:1 delta on the manifolds, which basically never happens), then cracking the wastegate piston at 10psi means you can only make a max of 10psi in the intake side.
The spring pressure is a situation where you don't even have a reference line hooked to the wastegate, in which case he said it was a 16psi spring, which would crack the piston side at 16psi exhaust manifold pressure. This would equate to like 8psi intake manifold side, with a 2:1 delta pressure across the turbo.
Right. Back pressure plays a huge part in actual pressure to open the piston. On a car with higher back pressure it’s going to lower the boost pressure to open the gate on a top vented setup. This was done on a 67mm 1.25ar turbo on a 2.5L engine. So there really isn’t much back pressure (or boost until about 4th gear for that matter) but yeah, you’re correct. This was more or less to show an easy way to get an idea of what spring you have in your gate. Most of the time this works well for getting into the ballpark. Unless you’re setup has excessive back pressure. But that’s what back pressure sensors and data logging are for if you want to get more precise.
Will the valve move by hand
good. so let me understand. you introduced air into the actuator or removed air from it by creating a vacuum. Because I do not understand?
An air compressor adds compressed air... He introduced compressed air through the regulator into the wastegate to actuate the valve to stimulate exhaust pressure on the valve in a turbo car.
Don't you have to take into account the pressure on the face of the valve? I mean what you did isn't wrong, but pressure on the valve could lower the springs effective pressure and the actual hotside pressure it takes for the valve to crack open?? I am learning, just asking, not trying to berate you.
Never had a turbo still don’t so what’s the psi to spring pressure ratio? if that’s even a thing why do you gotta check the spring pressure for?
The spring pressure of the wastegate determines what boost pressure (intake charge pressure) that the wastegate opens to hold/limit the boost.
In this case, the turbo will always hit a peak of 12 psi. You can add a boost controller to raise it above that 12 psi, but you can't lower peak boost below 12 psi.
Wrong. The point or pressure where the valve first moves in you test is not the boost pressure you will get. It will be at least 2 psi lower due to exhaust manifold pressure making it open at a lower inlet manifold pressure.