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new problem losing oil pressure upper rpm's

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mixed up View Drop Down
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Post Options Post Options   Thanks (0) Thanks(0)   Quote mixed up Quote  Post ReplyReply Direct Link To This Post Posted: Oct/19/2021 at 12:59am
try running a thinner oil it sound like you sucking the pan dry it happened to me in my 290 at top end I would see the drop in oil pressure
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Boris Badanov Quote  Post ReplyReply Direct Link To This Post Posted: Oct/19/2021 at 5:44am
Originally posted by mixed up mixed up wrote:

try running a thinner oil it sound like you sucking the pan dry it happened to me in my 290 at top end I would see the drop in oil pressure

DITTO.

Your oil is in the valve covers and in the back of the lifter gallery.
Age old AMC nightmare. They were not designed for racing, just transportation.


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Post Options Post Options   Thanks (0) Thanks(0)   Quote Trader Quote  Post ReplyReply Direct Link To This Post Posted: Oct/19/2021 at 12:24pm
Many articles state that you should always stay within 2 weight grades. i.e. 10W30, 5W20, 0W20 ... for a modern engine. Most NASCAR is now running 0W16.
Deviation from the 2 weight grades is were they state you run into stability issues with film thickness ...  unless the manufacturer has recommended the oil.
My Son's BMW recommends a 5W40 LL Euro grade that is the most extreme spread I've seen from the manufacturer. It has a 7500 RPM red line.
Trying a race oil in the 10W30 range should not hurt anything unless your overheating has caused excessive wear.
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Post Options Post Options   Thanks (0) Thanks(0)   Quote PHAT69AMX Quote  Post ReplyReply Direct Link To This Post Posted: Oct/19/2021 at 1:27pm
Posted May 25, 2012 on the CRG Forum by user "Pigpen" who just happens to be Edward Gene Owen (pictured center) TRACO employee 1965-75 quote : "Small block Fords and AMC's had a lot more room in the lifter valley and around the crank, so oil tended to get trapped."
imho most likely cause is inadequate drainback to the pan.
When seeing hoof prints, think horses, not zebras... at least in the U.S.A. Big smile
No how or what may be preventing said drainback is a whole different set of various possibilities.
Oh & look, seems as if Traco found a successful way to install
the AMC motor oil dipstick tube without breaking the darn thing !
Peace




Edited by PHAT69AMX - Oct/19/2021 at 1:29pm
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Post Options Post Options   Thanks (0) Thanks(0)   Quote jcisworthy Quote  Post ReplyReply Direct Link To This Post Posted: Oct/19/2021 at 4:28pm
Years ago the same thing happened with my friends 360 in his Ambassador wagon. 

Drained the oil and was able to peek through the fill hole and saw the pickup was close to the bottom of the pan. 

Got in there with a long blunt something, don't remember what, and I was able to tap the pickup above the pickup screen and tighten it back up plus gain clearance. Problem was solved 
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matty 401 View Drop Down
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Post Options Post Options   Thanks (0) Thanks(0)   Quote matty 401 Quote  Post ReplyReply Direct Link To This Post Posted: Oct/21/2021 at 8:22am
i picked some 10-30 racing oil  will change it out and see what happens 
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Post Options Post Options   Thanks (0) Thanks(0)   Quote amxron Quote  Post ReplyReply Direct Link To This Post Posted: Oct/21/2021 at 11:24pm
The faster you accelerate the quicker you suck the oil pan dry!

Ease up to 6000rpm in 2nd gear, if you still have pressure just add a quart for safety.

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Post Options Post Options   Thanks (0) Thanks(0)   Quote matty 401 Quote  Post ReplyReply Direct Link To This Post Posted: Oct/22/2021 at 8:04am
Originally posted by amxron amxron wrote:

The faster you accelerate the quicker you suck the oil pan dry!

Ease up to 6000rpm in 2nd gear, if you still have pressure just add a quart for safety.

Ron.
i am running the 1/8 mile  and already run 6 quarts with the filter 
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79 concord 2 door
72 matador 304 grasshopper
68 Rogue 406
93 Cherokee 4.0 5 speed

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Post Options Post Options   Thanks (0) Thanks(0)   Quote matty 401 Quote  Post ReplyReply Direct Link To This Post Posted: Jul/02/2022 at 1:53pm
can i run 7 quarts in a stock pan ? 
72 matador 401 the beast
79 concord 2 door
72 matador 304 grasshopper
68 Rogue 406
93 Cherokee 4.0 5 speed

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Post Options Post Options   Thanks (0) Thanks(0)   Quote jcisworthy Quote  Post ReplyReply Direct Link To This Post Posted: Jul/02/2022 at 4:14pm
What is your pickup to pan clearance? 

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