turbo oil feed
Discussion
A young guy asked me for my opinion on a turbo conversion on a VXR Corsa he has bought.
The turbo has seized,there has been some mods to the car manifold,air box i/cooler,hoses etc.
The first thing that struck me was that the original oil feed that comes from the filter housing has been blocked off and thenew feed was set up as I shall describe as simply as possible.
The oil pressure sensor has been removed and replaced with a fitting that allows a banjo fitting on one end and the pressure sensor to be screwed back in to one side.
The banjo bolt has a temp sensor fitted(which when inserted blocks the banjo bolt holes considerably)
This banjo fitting supplies 2 ft of 3/4" i.d hose up to a 13 row oil cooler mounted high up between the headlights.
the return 3/4" i.d hose carries on for 2 ft then another banjo fitting converts it to a more traditional sized feed pipe,this banjo bolt has a restrictor,the hose then carries on to the turbo.
Never had any real dealings with turbo conversions but plenty with factory turbo failures on many makes and understand the need for decent oil flow.
My thinking is thus:
surely the constant change in diameter of pipe work and cooler and the sheer quantity of oil between the pump and the turbo will badly affect the flow/pressure of oil to the turbo?
I`m not entirely convinced that the oil pump would be capable of sustaining or reaching pressure and flow for the quantity of oil that now sits between pump and turbo all through the pressure sensor feed.
I know it`s straight off the pump,but the quantity of `working oil` needed in an engine I.e. that being under pressure still is very little and that goes through quite a large hole to its destination in comparison to this `system` that`s being supplied by a 5 mm hole.
Also how long from start up would the pump take to fill and pressurize the system before actually pushing any meaningful quantity of oil through the turbo,bearing in mind that oil flows back from the elevated cooler quickly upon turning off the engine (no return valve in the system anywhere)?.
Or am I missing something? and lastly wouldnt an oil cooler serve better purpose plumbed at the filter?
The turbo has seized,there has been some mods to the car manifold,air box i/cooler,hoses etc.
The first thing that struck me was that the original oil feed that comes from the filter housing has been blocked off and thenew feed was set up as I shall describe as simply as possible.
The oil pressure sensor has been removed and replaced with a fitting that allows a banjo fitting on one end and the pressure sensor to be screwed back in to one side.
The banjo bolt has a temp sensor fitted(which when inserted blocks the banjo bolt holes considerably)
This banjo fitting supplies 2 ft of 3/4" i.d hose up to a 13 row oil cooler mounted high up between the headlights.
the return 3/4" i.d hose carries on for 2 ft then another banjo fitting converts it to a more traditional sized feed pipe,this banjo bolt has a restrictor,the hose then carries on to the turbo.
Never had any real dealings with turbo conversions but plenty with factory turbo failures on many makes and understand the need for decent oil flow.
My thinking is thus:
surely the constant change in diameter of pipe work and cooler and the sheer quantity of oil between the pump and the turbo will badly affect the flow/pressure of oil to the turbo?
I`m not entirely convinced that the oil pump would be capable of sustaining or reaching pressure and flow for the quantity of oil that now sits between pump and turbo all through the pressure sensor feed.
I know it`s straight off the pump,but the quantity of `working oil` needed in an engine I.e. that being under pressure still is very little and that goes through quite a large hole to its destination in comparison to this `system` that`s being supplied by a 5 mm hole.
Also how long from start up would the pump take to fill and pressurize the system before actually pushing any meaningful quantity of oil through the turbo,bearing in mind that oil flows back from the elevated cooler quickly upon turning off the engine (no return valve in the system anywhere)?.
Or am I missing something? and lastly wouldnt an oil cooler serve better purpose plumbed at the filter?
Pictures or a schematic would be a great help.
If you dont think the turbo has enough oil supply. Remove the oil feed and crank the engine over ( disable engine from starting )
You should get a good flow of oil at the turbo quite quickly.
But if there is any doubt about what some numpty has retrofitted....change it all back to standard. You know that will work.
If you dont think the turbo has enough oil supply. Remove the oil feed and crank the engine over ( disable engine from starting )
You should get a good flow of oil at the turbo quite quickly.
But if there is any doubt about what some numpty has retrofitted....change it all back to standard. You know that will work.
Certainly,
I have had a better look today.
The car has less than 20k showing and working from invoices and receipts etc.we have found that the turbo seized roughly 400 miles from having the cooler fitted and the replacement,the now seized turbo looks to have lasted less than 20!
The original feed has a grub screw fitted and then dot punched round the edges,as it`s a push and turn fitting originally the filter housing will need replacing(£350) just to use the proper feed.
He drove the car for 120 miles home with no problems and said that apart from being painfully slow the car was fine,the engine sounds as it should and oil pressure was good.
Cranking it with the oil feed open there is a gush of oil,but it was more the fact that it had to fill and pressurize that entire system, firstly through a 5mm hole added to the possible implications of its many changes in pipe diameter and restrictions before supplying the turbo,as it drains back when turned off.
That`s with out imagining what may be going on while the car is under motion with g forces working their part of the equation.
I have had a better look today.
The car has less than 20k showing and working from invoices and receipts etc.we have found that the turbo seized roughly 400 miles from having the cooler fitted and the replacement,the now seized turbo looks to have lasted less than 20!
The original feed has a grub screw fitted and then dot punched round the edges,as it`s a push and turn fitting originally the filter housing will need replacing(£350) just to use the proper feed.
He drove the car for 120 miles home with no problems and said that apart from being painfully slow the car was fine,the engine sounds as it should and oil pressure was good.
Cranking it with the oil feed open there is a gush of oil,but it was more the fact that it had to fill and pressurize that entire system, firstly through a 5mm hole added to the possible implications of its many changes in pipe diameter and restrictions before supplying the turbo,as it drains back when turned off.
That`s with out imagining what may be going on while the car is under motion with g forces working their part of the equation.
Edited by shoehorn on Wednesday 11th September 18:54
Megaflow said:
Plus that oil cooler is a total waste as it only cooling the oil to the turbo.
I did mention in my original post that I thought the cooler was better served being plumbed off the filter and really cant understand why this is set up this way.This set up I first feared was the work of a well meaning but naive individual.
The owner of the car has done some more digging and sent me a link.
It transpires that a specialist tuner supplies the parts or carries out the conversion,
I saw the pictures and read the blog with my very own eyes and it is the same conversion being carried out on another VXR on the net.
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