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What kills a turbo quickly, and can seize the shaft almost instantly is a lack of oil supply, and as your oil supply is custom made for a BB core it may be insufficient. Ball bearing turbo's require only a little oil, at lower pressure, while the bush core I assume you have now will need a higher unrestricted flow. Do you know if there is a restrictor in the oil line?

The easiest way to check the turbo is getting enough oil flow is to drop the drain hose off the bottom of the turbo and run a hose to a jar or similar, measuring the oil flow in a minute or so. Ask Stao for an approximate flow level. He is generally very helpful when it comes to fixing issues, you should discuss it with him first I think. There is no chance you could bugger the tolerances to produce that much lag, there would have to be 1/2 an inch gap between the turbine and it's housing.

If the turbo is now bush cored, the shaft will have a little in-out movement, and side to side. The oil is what centres the shaft, it should never touch the bush.

Where are you taking your wastegate pressure from?

The side port goes to intake pipe just before the TB

The top port goes to my boost solenoid, which then has the other port going to my TB spacer and the front port vent to air

My HALTECH Map also goes to TB spacer

My Fuel reg and boost gauge also goes to TB spacer

What kills a turbo quickly, and can seize the shaft almost instantly is a lack of oil supply, and as your oil supply is custom made for a BB core it may be insufficient. Ball bearing turbo's require only a little oil, at lower pressure, while the bush core I assume you have now will need a higher unrestricted flow. Do you know if there is a restrictor in the oil line?

The easiest way to check the turbo is getting enough oil flow is to drop the drain hose off the bottom of the turbo and run a hose to a jar or similar, measuring the oil flow in a minute or so. Ask Stao for an approximate flow level. He is generally very helpful when it comes to fixing issues, you should discuss it with him first I think. There is no chance you could bugger the tolerances to produce that much lag, there would have to be 1/2 an inch gap between the turbine and it's housing.

If the turbo is now bush cored, the shaft will have a little in-out movement, and side to side. The oil is what centres the shaft, it should never touch the bush.

i somehow missed this, i will text him today, thanks for the ideas scotty !!

Yes there is a filter (not sure if some thing as restrictor) in the line, just before the oil pump side of sump?

When you say drain hose, the one coming from turbo going to sump (passenger side) ?

Yep, drop the drain hose to the sump and check the oil supply, try and measure what flows in a set time period so you can let Stao know.

The filter is to clean the oil so the ball bearings last longer. If he has put a bushed core in it probably isn't required, but it won't hurt, unless it gets blocked...

Yep, drop the drain hose to the sump and check the oil supply, try and measure what flows in a set time period so you can let Stao know.

The filter is to clean the oil so the ball bearings last longer. If he has put a bushed core in it probably isn't required, but it won't hurt, unless it gets blocked...

He said it should fill up 500ml in 30sec and yes its bush cored.

so just have the engine on idle with this test?

I cant find the flow rate of the oil pump.. i have the rev up one from 06 model DE

It hasn't got much to do with the oil pump, more the oil feed line to the turbo as the ball bearing cores usually have restrictors inline. VQ's run fairly high oil pressure too.

Yep, see what happens at idle and let him know the result, I imagine the turbo was installed with all the same parts so perhaps the oil feed fitting on the turbo still has the small hole to act as a restrictor? You might need to get it drilled out. Hopefully there is no long term damage to the turbo yet.

It hasn't got much to do with the oil pump, more the oil feed line to the turbo as the ball bearing cores usually have restrictors inline. VQ's run fairly high oil pressure too.

Yep, see what happens at idle and let him know the result, I imagine the turbo was installed with all the same parts so perhaps the oil feed fitting on the turbo still has the small hole to act as a restrictor? You might need to get it drilled out. Hopefully there is no long term damage to the turbo yet.

He replaced the banjo bolt so it doesnt have a restrictor, i used the fittings he supplied as the ones that came with the turbo were too small.

Let you know what happens this weekend.

A waste gaye wont open if the car isnt under load

Free reving it wont make boost

We also forced air into top of the wastegate, no change. Upon driving the car with the return pipe removed and waste gate vented to air i could not hear anything from it.

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