Oil pressure

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Challenger392
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Oil pressure

Post by Challenger392 »

On my last few runs at Ascutney this past weekend I notice that in hard right hand corners I was getting a fairly large oil pressure drop. It dropped fast enough to make me believe the pickup was either out of the oil or air was getting into the system somehow. The pressure also seemed a little slow to recover when coming off high power,as in when I would cross finish and slow down quick the pressure would dip well below its usual operating pressure and then fairly slowly recover. I checked the oil there is plenty. Thanks to my oil accumulator it was never really dangerously low. Im going to drop the pan when I get a chance and check everything out to make sure everything is ok. Anyone have any suggestions of what it might be? Could the oil pump just be going? Could the pickup pipe have loosened up over all the bumps at Ascutney? Any input would be greatly appreciated. Thanks
Luke Moultroup
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Pratt & Whitney Engine Services

http://moultroupracing.blogspot.com/

2012 Dodge Challenger SRT8 392
1972 Dodge Challenger 318
2006 Jeep Grand Cherokee 5.7
2004 Mazda 6
Howe Modified
1989 Suzuki GSXR1100K
Mopar 151w2
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Re: Oil pressure

Post by Mopar 151w2 »

Wet sump oiling is always gonna be a marginal thing in a P-1 car, for about 75 different reasons. ( And if you have 3 hours, I'll tell you all about 'em - but you know that) In your current state, I'd A)check the pickup-to-pan clearance B) try running the inital fill a quart (or even 2) higner - is the volume in the accumulator under pressure being allowed for? C) Upgrade to the 3-quart "full size" accumulator 8-)
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Challenger392
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Re: Oil pressure

Post by Challenger392 »

Good point I hadn't thought about what the oil level would be once the accumulator fills. I'll drain the accumulator top off the oil and then add the 1.5 quarts the accumulator takes and see how that goes.
Luke Moultroup
Technical Support
Pratt & Whitney Engine Services

http://moultroupracing.blogspot.com/

2012 Dodge Challenger SRT8 392
1972 Dodge Challenger 318
2006 Jeep Grand Cherokee 5.7
2004 Mazda 6
Howe Modified
1989 Suzuki GSXR1100K
Chief Geek
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Re: Oil pressure

Post by Chief Geek »

On an entirely different topic...

Congrats to Luke for keeping a P1 car shiny-side-up all weekend. I had 2 "serious moments" with my 98 hp and would certainly have been in the weeds if I had any more.

Paul
"Christina", New #13/#55x, '90 Miata: In progress
"Keiko", Old #13x/#55x, '96 Miata: R.I.P.
Daily Driver: '11 Mazda2 (small cars... some men have nothing to compensate for)
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sachilles
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Re: Oil pressure

Post by sachilles »

Chief Geek wrote:On an entirely different topic...

Congrats to Luke for keeping a P1 car shiny-side-up all weekend. I had 2 "serious moments" with my 98 hp and would certainly have been in the weeds if I had any more.

Paul
I'd agree with that. I think all the folks completing their first hill climb(or first Ascutney) this weekend did a remarkable job.
Sachilles
02 Subaru impreza (Donut) #66
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Challenger392
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Re: Oil pressure

Post by Challenger392 »

Thank you for the vote of confidence, I had a great time, the car exeded all my expectations.
Luke Moultroup
Technical Support
Pratt & Whitney Engine Services

http://moultroupracing.blogspot.com/

2012 Dodge Challenger SRT8 392
1972 Dodge Challenger 318
2006 Jeep Grand Cherokee 5.7
2004 Mazda 6
Howe Modified
1989 Suzuki GSXR1100K
Chief Geek
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Re: Oil pressure

Post by Chief Geek »

Mopar 151w2 wrote:Wet sump oiling is always gonna be a marginal thing in a P-1 car, for about 75 different reasons. ( And if you have 3 hours, I'll tell you all about 'em - but you know that) In your current state, I'd A)check the pickup-to-pan clearance B) try running the inital fill a quart (or even 2) higner - is the volume in the accumulator under pressure being allowed for? C) Upgrade to the 3-quart "full size" accumulator 8-)
I'd have bet pretty big money that John R had been around this block before.

Luke: I'm betting this issue is common enough that there is an off-the-shelf/easy fix. I'm sure John, Sherman, and other people familiar with push-rods and other "very mature" technologies will know where to look. ;)
"Christina", New #13/#55x, '90 Miata: In progress
"Keiko", Old #13x/#55x, '96 Miata: R.I.P.
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Re: Oil pressure

Post by Mopar 151w2 »

When considering an "easy fix", please return to Line 1 - "Always gonna be marginal."
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sdwarf36
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Re: Oil pressure

Post by sdwarf36 »

Mopar 151w2 wrote:When considering an "easy fix", please return to Line 1 - "Always gonna be marginal."
Agreed.
The road race Mustang engines I do at work have tens of thousands of dollars spent doing r+d on wet sump pans. Its the weak link right now.
Luckily, we don't have too many long sweeping rights (turn 2 at Okemo is the worst).
The road race pans have a square box in the middle of the sump-with 4 trap doors opening inwards to allow oil to the pick up. It might be worth looking around ebay or racingjunk to see if you can stumble across one. (Ask about pan depth before you buy it.)
Translating road racing to hillclimbing:
Proper tire selection== nothing hooks up on moss or wet leaves.
Staying on the racing line==anything paved is considered good.
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Re: Oil pressure

Post by Mopar 151w2 »

If the pan on the car is the one I'm familiar with, it was built from a Moroso "U-weld-it" kit, roadrace version. :geek: Part of the issue has to do with depth - It was built at stock depth, due to ground clearance issues on the old car, and requires a small - diameter starter to fit on the car at all.
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