What else to solve high oil pressure?

[knochgoon24]

Background:
Balance Shafts removed. Holes plugged.
Ported OFH
Blown several turbo's (16g's) from oiling issues. Weird damage too.

Right now I'm running 5w-40 oil. I see cold start (~65*F here right now) oil pressures of 80psi. Warm idle oil pressure is 20psi. If I try using something like 10w-30, my oil pressure is barely 10psi at idle, especially after a hard run. I saw as 5psi in the summer with overdue oil. So I need the slightly thicker oil. Engine has unknown mileage, but chances are it has a ton.


Problem:
Oil pressure quickly climbs with rpm. By 4000rpm my oil pressure is 80psi. By 5k I'm past 100psi. The gauge pegs at 120psi around 6k.

Both 5w-40 and 10w-30 give me similar numbers.


Failed Fixes:
I've tried porting the oil filter housing. Can't port it any bigger.
I've made sure the turbo oil return isn't blocked.
I've tried different oil filters. No difference.

For a while, my current turbo (small 16g) was happy spinning away at 15psi while I fixed other problems. I didn't really beat on the car since it was rebuilt last. It almost never saw past 5k. I thought all was well, but now that I'm turning the boost back up and beating harder on the car, I'm starting to see smoke out the tail pipe. The valve stem seals are new so it's not those.

The turbo is being fed from the OFH because the last one died when I tried to feed it from the head and run 20psi with it. The damage was odd. The bearings were shot, the shaft was worn down, but there was absolutely no bluing of the shaft anywhere. This is the other reason I've since switched to 5w-40.


As far as I've found, I'm left with either:
-adding a restrictor in the feed line to the turbo and keeping the +120psi.
-repeatedly cutting the oil pressure relief valve spring until my peak oil pressure drops to a reasonable level.
-Build an adjustable oil pressure regulator for the oil feed line.

From what I've found the general consensus is 10psi + 10psi/1000 rpm. And that the stock relief valve should be holding pressure to 82psi. I don't know where that number came from, but I've seen it a few places while searching.


Any ideas on what I should do at this point? Should start cutting the spring?

 

[AlphaVision]

I am not a big expert on this so my opinion may not be relevant, but have you enlarged the oil port on the head?

 

[Artago]

Two thing's I've done on my motor to lower oil pressure.

1. Put a couple crush washers under the big bolt (22mm I believe) on the OFH. This will back the bolt/spring/piston out by 1-3mm.

2. Take the spring out and compress it using a long bolt, a couple of big washers and a nut. Only compress is by about 5-10mm. Then take a blow torch and heat one end of the spring. This will shrink it. Careful how much heat you apply. I over did it with a spring and made it too short. Luckily I had a spare. Heat it little by little until you shrink the spring by your desired amount. I dropped the hot spring into some oil after each heat cycle to cool it down.

Questions? Comments?

Tom

 

[dsmtalontsi95]

Look into an oil cooler. That leaves more area that will releave a little pressure do to adding more volume for oil to fill.

 

[Hubbell91Tsi]

Dont put a damn oil cooler on it, they are about worthless, you rev the car high enough and it leaves the pan dry. Thats why people like Shep and Curt Brown dont run them. Thats another reason Shep had the "push clutch and pull chute" note on his Dash, he was spinning bearings when he was slowing the car down with the engine (at like 9500rpm).

 

[LiquidX]

What's the spring pressure of the relief spring when it's not compressed? The only thing that I can think of that would work well would be to relieve tension onto the internal valve/piston which would be shortening the spring or lowering it's compression rate by directly altering the spring via heat and # of coils.

I believe you would still want a way to flatten the bottom of the spring if you cut it as it will want to try and spin which could cause metal flakes to appear. Perhaps a grinder to the bottom?

 

[habitatguy187]

Out of curiosity is there any air blowing out of the valve cover breather with the engine on and at idle?

 

[rich3389]

+2 on shortening the spring...
On my 6 bolt with no BS and ported OFH, I have a cold start of just under 75 psi, 12psi hot idle, about 60 psi at 3krpm and oil pressure max's at around 75 psi from 4k up. Those would be numbers I would shoot for.

On a side note, my car was having the same smoke issues(new turbo and perfect compression), I found that the catch can I had between the valve cover vent and intake was causing enough restriction, and removing the catch can and just running a hose just like stock cured the issue.

 

[knochgoon24]

Two thing's I've done on my motor to lower oil pressure.

1. Put a couple crush washers under the big bolt (22mm I believe) on the OFH. This will back the bolt/spring/piston out by 1-3mm.

2. Take the spring out and compress it using a long bolt, a couple of big washers and a nut. Only compress is by about 5-10mm. Then take a blow torch and heat one end of the spring. This will shrink it. Careful how much heat you apply. I over did it with a spring and made it too short. Luckily I had a spare. Heat it little by little until you shrink the spring by your desired amount. I dropped the hot spring into some oil after each heat cycle to cool it down.

Questions? Comments?

Tom

I didn't even think of the crush washer idea. That would be reversible if I found that wasn't helping. I might try that first. And it is 22mm.

Out of curiosity is there any air blowing out of the valve cover breather with the engine on and at idle?

Nope. It actually sucks air in.

On a side note, my car was having the same smoke issues(new turbo and perfect compression), I found that the catch can I had between the valve cover vent and intake was causing enough restriction, and removing the catch can and just running a hose just like stock cured the issue.

The hose I have hooked up to that is shorter and larger than stock. It runs to a catch can that then vents with a breather filter. I'm running SD, so it's not messing with the air metering. PCV valve works well too. I'm pretty sure my crankcase pressure is in check.

 

[99gst_racer]

Dont put a damn oil cooler on it, they are about worthless, you rev the car high enough and it leaves the pan dry. Thats why people like Shep and Curt Brown dont run them. Thats another reason Shep had the "push clutch and pull chute" note on his Dash, he was spinning bearings when he was slowing the car down with the engine (at like 9500rpm).

Oil coolers are not worthless and they also aren't the reason he had that note on his dash. An oil cooler won't have an affect on how much oil is in the sump at any given point, as long as you account for the amount of oil that the cooler and lines hold when you fill up.

Shep has that note on his dash to remind him to lower the engine RPMs and reduce his oil pressure and volume being distributed to the bearings. So that when the chute is out, there's less oil going to the head where it's not needed, and this helps combat starving the pick-up when all of the oil rushes to the front of the engine/pan. It has nothing to do with an oil cooler.

 

[Boug]

Just out of curiosity, what is a safe oil pressure operating range? I have an oil pressure gauge but that does nothing for me if I don't know what to look for. Thanks.

 

[hairybeanbag]

I never was able to find a way to lower oil pressure? I've done everything you listed and have always fought oil leaks. But what do you really expect? My last motor with out balance shafts had over 100 psi of oil pressure during cold start

After 4 years of looking at my car on jack stands, I finally bought a JDM motor and left the BS in place and Bought Kevlar belts. After driving the car this past weekend, I couldn't be happier!! Oil pressure is normal, car leaks nothing and I can actually drive it with out having to Carry a case of oil in the trunk!!

To be honest, With a light weight flywheel, I can't even tell the BS are still there! to each there own, but I'll never eliminate any BS's from my motors again.