for those with oil pressure guages and a turbo, what is your oil pressure at idle/cruising? mine has been a bit lower since the turbo install. would the extra volume/demand cause this? i know what the helms manual says...i'm interested in your experience...


[Modified by downpipe, 10:22 AM 11/26/2001]


[Modified by downpipe, 9:30 PM 11/26/2001]

 

i'm intrested too, my oil pressure defore the turbo install was around 80 psi cruising, now it's never about 60, whixh is good for the turbo seals, they shouldn't be subjected to high pressures, but i'm just wondering if this is good for the rest of the system.

 

I installed my gauge with the turbo so i don't have before and after numbers, but i would expect a drop due to extra volume going to the turbo. It doesn't take much unless you have really increased the feed line diameter.

I run about 55-60 psi at cruising rpms. 10-15 psi at idle.

Randy

 

mines wont go past 50psi.

 

with the addition of a turbo, there is more volume for oil to circulate....
increase volume will cause a...decrease in pressurre.
that is (during oil change) if u add the same amount of oil when your car was non-turbo..
as you do now...

increasing the amount of oil would definitely increase oil pressure!!

im no expert but i assume you guys should be adding a little more oil to your turbo motors
because oil feeding your turbo is less oil feeing your motor....!!

 

Adding oil is not going to increase pressure.

The reason the pressure is lower is because you've added another path for oil to travel from the oil pump back into the pan. If you've got electrical background - it's like adding another resistor in parallel - two parallel resistors present a lower total load; similarly two parallel oil lines present a lower backpressure on the oil pump than one alone. Adding volume to your oil pan will not change how much or how fast oil flows through your pump.

 

So then, should we be considering higher flow oil pumps like the Toda or Z10 units, or just porting the oil pump and shimming the spring .... to bring the oil pressure back up.

 

no elec background sorry.!!
im a biology major damit!!!
lol

true!!! increased volume.... less pressure...

the pump has a constant flow rate regardless of how much oil is added adnd regardless of the oil pressure...

maybe my chemistry is off when it comes to engines and oil pressure..

explain this....why did i have a major oil leak from my valve cover region after my younger sibling!!
added an extra liter of oil to my engine...and i went out for a rev feast.!!!!
i changed the dist seal, valve cover gasket, and i still have a little leak
to fiugure out...im assuming cam seal..

more oil, more pressure...same volume...there goes the seal!!

 

yep. sounds like mine, except when the engine is really cold and the oil is all thick.

 

Hmmm...I idle at 25psi or maybe a hair under and cruise at about 75psi (give or take).

My gauge isn't the most accurate though...it is a shortsweep elec autometer. This is under N/A and spraying.

-ryan

 

Put a .060 shim under the spring in the oil pump and that should give you an extra 10 lbs of running pressure. I'm not sure that you really need the extra pressure but it's an easy fix.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by earl &raquo;</TD></TR><TR><TD CLASS="quote">Put a .060 shim under the spring in the oil pump and that should give you an extra 10 lbs of running pressure. I'm not sure that you really need the extra pressure but it's an easy fix.</TD></TR></TABLE>

Sorry to bring the post back from the dead.

Earl -
Does the oil pump have to be removed in order to get the relief valve spring out? Or can it be done by dropping the oil pan.

 

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You can do this by just dropping the pan. Be careful because the spring will have 60 lbs of force behind it when you un-screw the fitting.

Even though adding oil will not increase pressure, it will lower available oil volume. I like to add an extra .5 of a quart to the pan when dealing with a turbo.

 

It also depends where you measure pressure from. Before I installed the turbo on my old car, I had a -3an line going into a Tee for my OEM oil pressure sender and my Defi sender. Oil pressure was 15-20 psi at idle and about 75 psi at full throttle after 3500rpms. After I ran another -3an line off the Tee to my turbo, my oil pressure gauge dropped to 5psi at idle and 50psi max. What was happening was that now that I added the other -3an line, the flow of the oil was rushing past the sending units and not measuring the actual pressure in the system. What I ended up doing was changing the original -3an line to the Tee to a -4an and my oil pressure was back to the original 15-20 at idle and 75 after 3500rpms.

 

Thank you AzG35. I figured that there was a reason my pressure changed when I T'd it, and the puny copper line probably didn't help either. Doesn't go above fifty with very slow response, but at least it tells me I have pressure.

 

I'm using the greddy block adapter + greddy oil gauge and I get ~15psi at idle and ~60psi at 3000rpm.

 

about 22 at idle....about a little under 60 crusing...
courtesy of defi