74 with a 2056 1 ½ seasons on it.
CB injection
Running 20W 50 Joe Gibbs GP-1
Dakota digital head temp gauge
Dakota digital oil pressure gauge and sender
Also still running stock sender and light in gauge
Not sure what temp oil sender is in the engine but the gauge is the one with the small red section.

I had the light flickering after autocross runs last year so I put the Dakota digital gauge on to see what pressures actually are.

This has become a huge stressor as now I am not sure if I trust the gauge or if the engine has issues.
The pressure is good when I start but drops to below 6psi at idle once warm, yet the stock light doesn’t come on.

I took some numbers last night to track it.
74 degrees ambient
Start up pressure 50 psi

After driving about 4miles oil temp gauge had just moved off the zero mark (case measured 165 degrees with IR thermometer)
12.5psi @idle

Drove some more
Oil temp gauge over the T
28.5psi @2400rpm
Drove more
Oil temp gauge between E/M Head temp 317 degrees (case measured 225 with IR thermometer)
26.5psi @ 3000rpm

Let the car sit for about 2hrs
Oil temp between E/M Head temp 300 degrees
15psi @3000rpm

Drove further ambient now about 68 degrees
Oil temp gauge over the M Head temp 315 degrees
10—12psi @ 3000rpm

Once I parked it and measured the case with the IR thermometer I was getting 180 -190 degrees.

Is it possible to have air stuck in the line going to the sender? If so would it cause inaccurate readings?

Does it sound like Chris’s/ Tangerine racing oil relief fix would help this?



Click to view attachment Click to view attachment

Double check with a "real" gauge as in old school

Different topic, but head temp nice at 315 for a 2056.

Unrelated to your post about pressure, what ECU etc are you running on this engine?

Phil

I have a 2056 in my 914. Running a CB performance 26mm Schadek oil pump along with Tangerine Racing oil pressure relief valve. Start up pressure is 78 lbs. at 1150 rpm. After the car is warmed up, I get 38 lbs. at 3000 rpm. Oil pressure gauge is a VDO 0-100 mechanical gauge. The pump was blueprinted to zero clearance with a steel cover. Used a .002 gasket between the cover and the pump with NO sealant. Running Driven 15/50 oil and I installed a Scat 1 1/2 qt sump for a total of 5 qts of oil with the K&N filter. Also running a Setrab oil cooler. Oil temp stays around 180.

ON hot days it will run up to 330

The ECU was Supplied by CB. It's their Gen 4 EFI

We you the one that had pressure issues and the pump fixed it? I spend the first part of the week reading old posts.

Oil pump change requires a engine drop correct?

Where did you get your pressure gauge? any chance you a model number? did you run a line up to the interior to mount it inside?

Very good!

Cool thanks for the info,
I dont have a pressure gauge currently but will add this soon, right now head temp wise i run similar temps , hot days or longer runs will be that 310-330 range but around town it rarely goes over 300, and oil temps stay under 200 iwth the aux cooler that Tangerine installed for my a few years ago on my oem 2.0 motor and kept that for this motor too.
but the fan running is a must on hot days, its set wit thermostat for automatic turning on and off. .

will hve to look at the CB system, im still on the D-jet.

Phil

Yes, I had a Shadek 26 mm pump that was under size resulting in low oil pressure. In order to change the pump, I would drop the engine. I had to fix a leaky cover gasket and did it with the engine installed. Had to drop the engine bar and the motor mounts to get to the cover, PIA.

Oil pressure gauge is a VDO Cockpit gauge 150-030. I ran a 120" 3AN SS braded line in the center tunnel from the gauge to the engine. ALLSTAR ALL46300-12. This is how I ran the sender to the fuel gauge. 12" line from the oil pressure port on the engine to the T fitting. Click to view attachment

Def verify with mechanical gauge and ensure the pressure relief pistons (main and the one between #1 and #2, if present) are operating correctly. If all is well there, then I’m sorry to say it’s likely main or rod bearings. Been there.

How do you verfy that the relief valvesx are working correctly?
My understanding is that just cause they move doesn't mean they are seatng well.

My second relief valve on the side of the engine is blocked off. I would install the Tangerine pressure relief valve and try that first. what oil pump are you running?

Have you been running her hard? any signs of metal in the oil?
Hopefully she's not cooked

Not sure if it's even relevant but I have heard people say retarding the time moves the heat from the head into the oil.

Your head temps are pretty low, and your oil is pretty warm.

However, when your bearings go, the pressure behaves as you describe. I would suspect sparkles in the oil.

When you say second valve is that the one under cyl 1 and 2? How did you block it off?

Stock type 4 pump

I ran 4 or 5 autoxs last year so that is pretty hard.
I am including an oil analysis. I don't see anything really bad in the oil filter when it is cut apart. I stil hve to inspect theone form this oil changeClick to view attachment

Get a real good mechanical gauge as your cold pressure is low as well as your warm idle,my last T4 built was 72psi cold and 10-12 psi after full warm up and that was just a topend build was good bottom end but rod bearings replaced with new.
Post your result but think you will be fine with the right gauge ,following this one,cheers.

On the main relief, check to make sure the piston seats fully at the top of the bore. The secondary between #1 and #2 can be blocked off with a slug that replaces the spring. Or you could just inspect / clean up the bore there as well.

But given your description of things, it's likely you have a bearing clearance issue. I hope it's not, but like i said, I've been there. And stayed in denial for a while. I finally bit the bullet and tore things down. Now that it's rebuilt, the pressure is great, even when the oil is 220...

I got my gauge yesterday and installed it this morning.

Start-up 65-70 psi

drove a little oil temp just off zero head temp 262
20 psi @idle

2600 rpm 58psi

oil temp coming onto the T head temp 265
3600 rpm 60 psi

16 psi @ idle

So that is way better than the digital gauge.

I'll drive it some more and I have an Autox this weekend so we'll see how it does with a bit more driving.
At least I have way less anxiety while driving it now.


Any thoughts on switching over tot he Tangerine racing pressure relief valve?

Well done ,pleased for you that you have WAY better numbers,sounds like you are good to go.
Don't know a lot about the Tangerine relief valve,think it approves cold and warm oil pressure ?,contact them and ask ,cheers.

Great news.

I was getting a blinking oil light at idle on a freshly rebuilt engine,

with stock oil pump and running VR1 20-50

Installed the Tangerine relief, and it solved that problem

No downside that I could think of.

Easy to get to also.

When measuring oil pressures what is the oil temperature?

I'd have to find the diagram the shows what temps correspond to the marks on the gauge

Need to double check with the oil temps in the 200 - 220 range. When my 2056 gets in the 200+ oil temp range my oil pressure runs about 45 - 50 at 3300 rpm's

I imagine that will be the case. I'll be driving it more tomorrow so we will get a better read on it.

That's about where mine sits (stock) at 220. After hard driving and high heat in the oil (230ish) the pressure will drop down to 7 at idle but rapidly climbs back to 12ish at idle as the oil cools. Still in that 40-45 range at 3000 at 230 though.

So I autocrosssed the car today. Ambient temp was close to 80.

Good Oil pressure all day, a little bit of light flicker at the end of the run but probably due to the finish being just after a fast tight right hander. Blip of the throttle and the light goes right off.


On the way home the oil had a chance to get a bit warmer. I am guessing 200 -210 range. I need to check the sensor part number next time I change oil.

Cruising at 3400rpm oil just under 40 psi oil temp probably 210 ish head temp 337

at idle oil 10psi

Might still look into Tangerines pressure relief valve

I get 38lbs. at 3000 rpm and 42lbs. at 3400rpm. Head temp around 210 (biral cylinders), oil temp just over 180 ( external oil cooler). Running Tangerine oil pressure relief valve, 26 mm CB Performance pump, secondary relief valve blocked. Oil pressure at 1050 rpm idle is 12lbs.

What is the ambient when you are seeing 180 oil temps? Does it ever get to the 200 - 230 range. is she fully warmed up? We have all heard the 10psi/1000 rpms, but I prefer a bit more. I like to see 40 - 50 psi an 3200 rpms

To the OP: it's possible your main/rod bearings opened up a bit last year after tracking her

Just for thought, we are about the same running around 40lbs. at 3000-3400 rpm. Should we also take into effect that the 26mm pumps are pumping a slightly higher volume of oil vs the stock 24mm pump, even though oil pressure is a tad on the low end? Higher pressures equal hotter oil.

Ambient temp was about 75 degrees, I have not had the car at the track, just spirited driving on NJ back roads.

Instead of adding pressure relief valves, (i have one) add an Accusump.

If you are autocrossing hard, you will starve for oil in tight corners.

I am on my 3rd or 4th engine with rod bearing failures due to low oil pressure.
I am sure that this is due to the G's on turns and my RPM's
I pull over 1.5 g's on turns and 7K on RPM's both conditions together will lead to the pickup pulling air and starving the rod bearings.
Like you it started with flickering oil light followed by rod knock followed by holes in the case from broken rods.

Hopefully you don't experience that.

1.5 G's, very cool. Does your engine have a windage tray?

Windage tray with Scat 1 1/2 qt deep sump.

How difficult to install and expensive is an accusump?
What tires are you running when you pull 1.5gs?

Check your voltage regulator, you should be putting out 13.5 to 14 volts not a little over 12.

Running Hoosier 225/15's
Accusump is not too outrageous. Few Hundred$$ but worth it if it saves a 15K motor.