Oil Pressure?

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JTG

JTG

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At normal operating temperature, where should the oil pressure be registering on the gauge for a 340?
 
Somewhere between here--------------------------------------and here. :D

Couldn't help myself.
There are so many variables for that.

temp
oil type and viscosity
oil pump type
oil level
rpm's
engine condition
bearing clearances

and on and on

General rule is a minimum of 10lbs per 1000rpm's at idle.
 
Sometimes it just depends on how tight the tolerances were on the build. My first 340 had 20 lbs. at idle. The one I just built had 40 lbs. at idle when hot.
 
Lol trailbeast XD. About 45-65 on start up and 8 psi is the the minimum for warmed up idle. Mine is 25-30 at warmed idle with 5w-50 just for comparison
 
Mine is 65 cold 40 hot and daily blasts to 6800.everyday for 8 months now...
 
TrailBeast said:
Somewhere between here--------------------------------------and here. :D

Couldn't help myself.
There are so many variables for that.

temp
oil type and viscosity
oil pump type
oil level
rpm's
engine condition
bearing clearances

and on and on

General rule is a minimum of 10lbs per 1000rpm's at idle.
Click to expand...

Cars normal operating temperature is 180
Oil is Vavoline race oil 20w50, car takes 6 quarts total (Kevko oil pan) car also has heavy duty external oil cooler.
Oil pump is a high flow rate Melling
Only 500 miles on rebuild 340
I do not know the bearing clearance
I believe the car at warm idle is showing 25psi on the factory gauge
 
Put a good name brand mechanical gauge on it with a "t" compare it to the factory gauge.
This will show variance in the factory gauge.
If you are real creative, you may be able to hide it under the dash and make it permanent for reference.
 
Or if you just want to pick up a gauge you can get a couple alligator clips to hook up the wires temporarily under the hood. Crank it and see what it reads and when done, unhook it.
 
Why 20w50 in a newly built (street?) motor?
Why a HiVol pump on a newly built (street?) motor?

With these specs you should have about 70 psi at idle, and be able to run 10w40 or thinner easily.


I'd also advise to install a good mechanical oilpressure gauge first.
If that shows the same it might be possible the oilpump's pressure check valve is hanging open.
 
JTG said:
Cars normal operating temperature is 180
Oil is Vavoline race oil 20w50, car takes 6 quarts total (Kevko oil pan) car also has heavy duty external oil cooler.
Oil pump is a high flow rate Melling
Only 500 miles on rebuild 340
I do not know the bearing clearance
I believe the car at warm idle is showing 25psi on the factory gauge
Click to expand...

There will be varied oppinions on your specs, but it wouldn't concern be a bit with those readings.
It SURE wouldn't be worth tearing into anything.

Not in my oppinion.
 
BigBlockMopar said:
Why 20w50 in a newly built (street?) motor? Why Not?
Why a HiVol pump on a newly built (street?) motor? Why Not?

With these specs you should have about 70 psi at idle. He has the high VOLUME pump, not the high PRESSURE spring...
Click to expand...

There's nothing wrong with running the high volume pump. I've been running them for years with the high pressure spring and have had no problems.
 
BigBlockMopar said:
Why 20w50 in a newly built (street?) motor?
Why a HiVol pump on a newly built (street?) motor?

With these specs you should have about 70 psi at idle, and be able to run 10w40 or thinner easily.


I'd also advise to install a good mechanical oilpressure gauge first.
If that shows the same it might be possible the oilpump's pressure check valve is hanging open.
Click to expand...

My engine is not a stock 340, its more of street / strip.

I picked up a Autometer gauge the other day, just haven't installed it yet.

According to the factory gauge, I've never seen this car at 70psi when idling hot or cold. Seems the car likes to always float around 25psi.
 
sireland67 said:
Put a good name brand mechanical gauge on it with a "t" compare it to the factory gauge.
This will show variance in the factory gauge.
If you are real creative, you may be able to hide it under the dash and make it permanent for reference.
Click to expand...

I plan to keep the factory gauge operationally injunction with the Autometer to compare the two readings.
 
krazykuda said:
There's nothing wrong with running the high volume pump. I've been running them for years with the high pressure spring and have had no problems.
Click to expand...

Krazycuda, or Trailbeast what is your thoughts on the 20w50?
 
moper said:
What is it cold at idle? What is it hot at 3500? Cold at 3500?
Click to expand...

Instead of me sort of guesstimating through memory, I will get the exact numbers when I start this car in the following day.
 
JTG said:
Krazycuda, or Trailbeast what is your thoughts on the 20w50?
Click to expand...


20w50 is fine for summer weather in the old cars. I run it all the time. I like to switch to a 10w30 or 40 for winter.


I tried 5w30 weight oil in a 318 once and didn't like it. Too thin....
 
JTG said:
Krazycuda, or Trailbeast what is your thoughts on the 20w50?
Click to expand...

Pretty much the same as Krazycuda, but I ran 20-50 all year.
Recently I swapped to Rotella T 15-40 for the zinc, just to see how it liked it, and it does.
Nice quiet lifters and rockers, and the Rotella is a bit cheaper that Castrol 20-50.
My car is a daily driver though, so it pretty much runs normal driving RPM's 90% of the time.
 
My oil pressures with 15-40 oil:

------------Cold-----Hot
Idle--------70lbs----(20-25lbs)
3000+RPM--80lbs----(65-70lbs)

My car is the opposite of the OP, more like strip/street (90/10). I too have a high volume pump. I have run 10-40 with no issue, 10-30 was a little too thin for my liking (oil pressure was only 55lbs hot at high RPM). I have my clearances written down at home from when I built the motor, but it probably won't help if you don't know yours.
 
TrailBeast said:
Pretty much the same as Krazycuda, but I ran 20-50 all year.
Click to expand...


I would use 20w50 all year if it was warm here like down there... :glasses7:


But I have to deal with the Chicago winters getting below 20° F.... 8)

(Not that there's anything wrong with that...)
 
krazykuda said:
I would use 20w50 all year if it was warm here like down there... :glasses7:


But I have to deal with the Chicago winters getting below 20° F.... 8)

(Not that there's anything wrong with that...)
Click to expand...


Your oppinion :D
 
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