Some cooling issues with my car (oil temps and odd pressure readings)

Chris_Red_V8

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(Warning in advance, rambling ahead)

Background: Built a new coyote/roadrunner motor a while back. Went overboard on cooling and sensor package, and now have some weird symptoms that may be bad gauges or setup.

Setup: MMR1000/Roadrunner, Fluidyne radiator, MMR head cooling mod, Boss 302 Oil cooler, homebrew Air/Oil cooler (-10AN lines, supposed 20,500 BTU core), 302S Grilles, speedhut gauges in stock location with T, and in Moroso 10QT pan (total 12 QT capacity for system). 302S hood, wrapped headers (stock).

Symptoms:
Oil temps read 140 if not below if the ambient air is 70* or below and car is highway cruising. Can go 50 miles without fully warming the oil (as read by the gauge).
Oil pressure reads 70-90 on start, settles to about 20, and once coolant reaches about 160, oil reads no pressure on the speedhut gauge unless you blip the throttle (obviously I have pressure or the stock pressure switch would flip - I know it works unfortunately). That or my motor seems to run just fine without any oil pressure (jk)...

I did install a 180* oil thermostat last week to try to combat the temperature problem

Testing: I bought an IR thermometer to test with this evening.
After a 15 minute drive and 5 minutes of idling, the gauge showed 160 (climbed from 145 when I first parked). The Pan as shot by the thermo was 161, the oil cooler lines were 178 and 170 respectively at their fittings. The cooler core was 158 as best as I could shoot it. I am thinking something about that pan may be such that the sensor is getting more of a reading of the pan itself, which may be slightly lower temp than the oil itself. Still not sure why that would be the coolest place in the oiling system. This was all sitting idling in the garage without the car's fan operating. When it did operate, all temps dropped about 5-7*.

Some images of the setup:
maint5.jpg


maint8.jpg


oilcooler2.JPG


Can't see the gauge wiring, but I have good grounds on both gauges, oil temp is in insert in side of pan with an appropriate brass NPT adapter.

~70mph after 30 minutes continuous running, ~68* ambient. Pressure looks good, temp can't be right.
http://www.chris-wynne.com/coyote/oiltemp.JPG[/img]

My thoughts:
The system is too large a capacity for street use, however actual oil temps are higher than the gauge is reading. Is it possible both my gauges just read somewhat low? I'd be inclined to believe both read between 10-20% low. I'll email speedhut for further guidance, but anyone else have some thoughts on a car that seemingly runs too cool?
 

Chris_Red_V8

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Another update: Colder day (44 out) but I did wrap the core.

Blocking off the cooler core didn't seem to make a meaningful difference on a 25 minute drive.

Some more pictures:

The sender in the pan (note the secondary ground wrapped around it):
oil_sender.JPG


the cooler core:
oil_wrapped.JPG
 

Chris_Red_V8

Shiny.
Established Member
Joined
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Messages
436
Location
Scottsdale, Az
as a note to resolution on this, the sender was in an adapter which was in that massive pan which faced under the car. There was too much "heatsinking" of the nearby metal to cool air when driving to get a good reading. When I moved the probe to a sandwich plate near the oil filter, much better and direct readings were taken.

(hopefully don't net another infraction for posting resolution to this particular odd issue)
 

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