i just got done installing a single in my 1jz supra, and its over boosting like crazy. I tried turning down the boost but it wont, i have the turboXS boost controler and the XS 46mm waste gate can anyone help me figure out the problem please. on the waste gate it has two inlets one at the top and one at the side and on the boost controller it has one from the pressure of the turbo and one to the waste gate actuator. just some info so you guys could have an idea what im dealing with here.
Over boosting
- Thread starter mk111ricky
- Start date
I could be wrong but you should have a vac line hooked up somewhere so that there is a vac supply. None of this stuff doesn't work without vac
Which wastegate port are you hooked to? You should have the MBC plumbed between the turbo and the side port.
mobes said:
well i have a vaccum comming the back of the engine to the side to the wastegate and another vaccum line from the boost control which tees off to the BOV, to top of wastegate ,and to the vaccum source ( off intake Manifold)
mattsmall said:
Have you ever ran an xs power wastegate? Most people on these forums have nothing good to say about them, but they haven't ever ran them either. I have a HKS standard 40mm and a Ebay Hks knock off. I have torn them both apart and all the castings are exactly the same. The diaphram is slightly different but is the same elasticity and and thickness. I have ran both on the same car, using the same spring and they performed exactly the same. They both held slighly over the boost spring rating on a ported rotary, which are known for boost creeping just about any gate.
Oh, and it's the same way with the Greddy type S BOVs. I have a real and a knock off and it's all the same castings with just the makers name shaved off.
As for the boost creep problem, pull the hat off the gate and make sure the plunger is still bolted to the diaphram. I had the nut on the plunger to come off inside the gate and the car would make like a soild 18lb with a 10lb spring. Once I bolted it back together it made 12-13lbs on a ported 13B. Also, make sure the vac line is hooked to a good source of vac and that it is connected to the correct nipple on the gate itself...
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I could be wrong, but the vac to the boost control and from the boost control to the wastegate and that should be it. There should'nt be another vac supply to the wastegate. The boost control regulates vac to the wastegate that is how it adjust boost. It sounds like you have two vac supplies to the wastegate which I don't believe is correct. The bov Needs its own supply for when there is vaccum the bov opens.mk111ricky said:
turbodriz said:
so the bov needs its own vacc ? ok lets start over,
from boost controler > two lines 1. To waste gate and
1. to pressure side of turbo
( might i ask what is the pressure side of turbo ? )
On the wastegate > Two nipples, one on side and one on top
( which one should the boost control be connected to ? )
( what should be connected to the other nipple? )
PS. sorry to be a bother but the XS wastegate did not come with a manual. Thanks
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If you are overboosting, you have a vacuum leak/line that isn't sealed correctly, your wastegate is faulty, your boost controller is not set up properly, or it is faulty. That is the order of likelyhood that I would use to check.
You should hook it up like this:
Take the little hose off that goes from the turbo compressor housing to the wastegate actuator. One hose will come from your boost controller to the compressor housing, and one will come from your boost controller to the wastegate actuator.
If there is need for a third hose, as a pressure source [I used this for my electronic boost controller] the last hose will come from a pressure supply. I used a "T" from between the stock blow-off [recirculation] valve and the intake/3000 pipe area.
You should hook it up like this:
Take the little hose off that goes from the turbo compressor housing to the wastegate actuator. One hose will come from your boost controller to the compressor housing, and one will come from your boost controller to the wastegate actuator.
If there is need for a third hose, as a pressure source [I used this for my electronic boost controller] the last hose will come from a pressure supply. I used a "T" from between the stock blow-off [recirculation] valve and the intake/3000 pipe area.
O.k First off if you ever seen a ct26 there is a nibble on the housing. This would be the pressure side of the turbo. But you have a 1jz and a single which is not a ct26 so what I would say that it might get is pressure from the wastegate. Which would be the other nibble. Second off...Please this is off of memory so what I would suggest is that you try it and don't go crazy with the throttle. I will also p.m some other guys and get there output. But I believe that you would get the pressure side of one of the nibbles on the wastegate being that there is no nibble on the turbo. Try it and see. I know that only one nibble on the wg is used for boost control. I'm pretty sure that we are heading down the right track.
I would say the pressure side of the compressor would be from the area where the compressor side of both turbochargers merge.
I would agree but I don't believe there is a nibble there to run a line back to the boost controller which is required in the diagram. Which led me to believe that one of the nibbles on the wastegate would serve the purpose. The wg does control boost. Therefore one side of the wg gets all of the boost from the turbo. And I do believe this is a single turbo.drunk_medic said:
Wait, your 1JZ is a single turbo? I need some more information - is this a newer model 1JZ with single turbo and VVT-i? Or is it an older twinturbo 1JZ that was converted to single turbo?