ViperRichRT10
Enthusiast
Can anyone tell me what my oil pressure should be at idle stopped in neutral and when driving down the road in gear?
Thanks!
Thanks!
Who knows about oil pressure?
- Thread starter ViperRichRT10
- Start date
GTSnake
Enthusiast
Mine idles around 20-30 and goes up to 50 driving.
mad0953
Enthusiast
The gauge is not accurate by a long way. At idle mine is at about 40 psi warm or cold and stays at about 50 psi when driving warm or cold. I am changing to Mobil 1 0-40 at the next oil change and am wondering if the gauge will show any difference.
The only way to tell is to get an accuarate oil gauge or have it checked by your Viper Tech.
The only way to tell is to get an accuarate oil gauge or have it checked by your Viper Tech.
BDZ1984
Enthusiast
what is your car at???? my car is at 20 at idle on a HOT day and 45 under any kinda rpms. and IM running Mobil 1 15/50
My 02 is running at 20lbs at idle and 40 - 45 while cruising... I'm running Mobile 1 15/50. I plan on doing the ACR upgrade that I hear adds an additional 10lbs of pressure. (It eliminates the at idle diverter valve in the filter adapter).
BDZ1984
Enthusiast
I also planned on doing this mod to see if the oil pressure comes back up
Ron
Enthusiast
As stated, the factory gauge is worthless. Change the sender unit and your gauge will read 10~ 15 psi different than before.
A temporarily installed true mechanical (capillary) gauge on my Viper (non ACR) with 5w-40 Delvac 1 synthetic oil (Mobil 1 for diesels) reads as follows:
Cold:
Idle - 67 psi
2000 rpm - 80 psi
Hot:
Idle - 49 psi
2000 rpm hot - 74 psi
3500 rpm hot - 80 psi
5500 rpm hot - 65 psi
All looks good but wondered about the drop at the 5500 mark. Perhaps the pressure relief valve is opening and dumping when pressure gets beyond 80 psi?
Other ideas / theories?
Thanks
A temporarily installed true mechanical (capillary) gauge on my Viper (non ACR) with 5w-40 Delvac 1 synthetic oil (Mobil 1 for diesels) reads as follows:
Cold:
Idle - 67 psi
2000 rpm - 80 psi
Hot:
Idle - 49 psi
2000 rpm hot - 74 psi
3500 rpm hot - 80 psi
5500 rpm hot - 65 psi
All looks good but wondered about the drop at the 5500 mark. Perhaps the pressure relief valve is opening and dumping when pressure gets beyond 80 psi?
Other ideas / theories?
Thanks
UK Viper Nigel
Viper Owner
The Service Manual for '94 RT/10 (Section 9-35) says that the oil pressure measured at the oil pressure switch location should be:
10 psi at idle
45-75 psi at 3000 rpm
10 psi at idle
45-75 psi at 3000 rpm
GTSnake
Enthusiast
I think the ACR mod makes it harder for the air conditioning to work.
You may want to check into that before you do it.
You may want to check into that before you do it.
ViperRichRT10
Enthusiast
Mine is running about 25 at idle and 45-55 under acceleration. Sounds like I am on track. I did a piston swap (former creampuff) not too long ago and wanted to make sure I was in line with the rest of you. Don't remember what I was before the swap. Thanks for your help guys!
Ron
Enthusiast
The stock oil filter adapter limits flow through the cooler at idle to protect the efficiency of the AC condensor by minimizing the heat in front of it. As engine RPM increases, and in theory forward motion, the resulant oil pressure increase forces the bypass to open and allow flow through the cooler once again.
The ACR adapter has no pressure bypass, so oil flows through to cooler full time. AC performance suffers at idle bacause of it as the condensor is less efficent with the massive heat generator in front of it.
Reality is that (at least in my case) idle oil pressure is well above the bypass limiter and oil flows through the cooler full time anyway, though I'm sure an ACR adapter would flow even better. Also consider that if you drive your car in <32F temps, and ACR adapter might prevent your oil from ever getting hot enough to evaporate the impurities. Dodge in fact recommends that anyone driving extensively in cold temps not change to the ACR adapter.
By the way, GENI's had a temp bypass system. Cold oil bypassed the cooler, hot oil flowed through the cooler. In theory, a better system. Don't know why they switched.
What we really need is an oil temp gauge in addition to a real oil pressure gauge to properly monitor the variables.
The ACR adapter has no pressure bypass, so oil flows through to cooler full time. AC performance suffers at idle bacause of it as the condensor is less efficent with the massive heat generator in front of it.
Reality is that (at least in my case) idle oil pressure is well above the bypass limiter and oil flows through the cooler full time anyway, though I'm sure an ACR adapter would flow even better. Also consider that if you drive your car in <32F temps, and ACR adapter might prevent your oil from ever getting hot enough to evaporate the impurities. Dodge in fact recommends that anyone driving extensively in cold temps not change to the ACR adapter.
By the way, GENI's had a temp bypass system. Cold oil bypassed the cooler, hot oil flowed through the cooler. In theory, a better system. Don't know why they switched.
What we really need is an oil temp gauge in addition to a real oil pressure gauge to properly monitor the variables.
Tom F&L GoR
Enthusiast
You can try this:
oil temp gauge idea
oil temp gauge idea
Ron
Enthusiast
Hi Tom,
Any theories as to why the pressure drops at higher RPM's?
Thanks
Any theories as to why the pressure drops at higher RPM's?
Thanks
Tom F&L GoR
Enthusiast
I think it's something like this: the oil pump develops pressure to overcome the resistance to flow through the oil passages and bearings. It ensures delivery of the lubricant. Bearings don't really care about pressure, they care about fluid volume. The moving parts want something to slide over, and the pressure between those parts is orders of magnitude higher than oil pressure, so the 45 or 85 psi isn't enough to squirt it between parts. The parts themselve pull oil into the clearance gap. At higher speeds, the moving parts accept or require proportionately more oil volume and so the head pressure is less. In other words, the bearings' appetite for oil at faster speeds outruns the pump's ability to supply it.
It's kind of why a lawnmower and Model T engine survive with splash lubrication - once you deliver the oil, the moving parts will carry it to where it needs to go next.
It's kind of why a lawnmower and Model T engine survive with splash lubrication - once you deliver the oil, the moving parts will carry it to where it needs to go next.
Ron
Enthusiast
Thanks Tom, nothing I would have ever thought of but something that makes sense. As always, appreciate your insight!
Ron
Ron
2000_Black_RT10
Enthusiast
Somebody must be shooting for a high Post count. 
(friendly joke!)
There's no way oil pressure should drop at higher rpm without indicating a problem.
Either the pan is running out of oil, aeration (i.e. too much oil and the crank is whipping the oil into foam) or a clogged oil filter. Some have added a high volume pump and wonder why the oil pressure drops, it happens to those who don't realize the pump is sucking all the oil out of the pan and they need a deep sump (more oil).
Bearings, etc.. don't **** oil enough to which is implied, sure there's ancillary action, but not enough to **** oil at that rate.
(friendly joke!)There's no way oil pressure should drop at higher rpm without indicating a problem.
Either the pan is running out of oil, aeration (i.e. too much oil and the crank is whipping the oil into foam) or a clogged oil filter. Some have added a high volume pump and wonder why the oil pressure drops, it happens to those who don't realize the pump is sucking all the oil out of the pan and they need a deep sump (more oil).
Bearings, etc.. don't **** oil enough to which is implied, sure there's ancillary action, but not enough to **** oil at that rate.
Tom F&L GoR
Enthusiast
Knowing Ron's care, I assume it's not overfilled or too low; oil is fine, filter is good. Dodge didn't design oil pans to run dry at 5500 RPM (I hope.)
I can over simplify this by saying that it's like a long garden hose with a number of holes before the end (the bearing.) Take your thumb off the end and the volume (gallons/minute) goes up but the pressure goes down.
The piece of data that is always, always missing in this kind of discussion is "that rate." What is the flow rate in gallons/minute when the pump is attached to the engine? (I don't know either.) And we don't know which hole the thumb is on, nor which one is "let go" at higher speeds. It's a little different than sucking oil.
+1 more!
I can over simplify this by saying that it's like a long garden hose with a number of holes before the end (the bearing.) Take your thumb off the end and the volume (gallons/minute) goes up but the pressure goes down.
The piece of data that is always, always missing in this kind of discussion is "that rate." What is the flow rate in gallons/minute when the pump is attached to the engine? (I don't know either.) And we don't know which hole the thumb is on, nor which one is "let go" at higher speeds. It's a little different than sucking oil.
+1 more!
Ron
Enthusiast
Mike,
While of course you might be right, you challenge Tom at your own risk. Few here are as knowledgeable as he. Perhaps you need to do a search under his name to read up a bit.
****************************************************
Let dig in
1) What is the factual basis for your statement: "There's no way oil pressure should drop at higher rpm without indicating a problem"?
2) Either the pan is running out of oil: - No, 10 qts (2000 MY oil pan) exactly at the fill mark.
3) aeration (i.e. too much oil and the crank is whipping the oil into foam): - No, see above
4) clogged oil filter: - No, new K&N oil filter installed 300 miles ago
5) Some have added a high volume pump: - No, zero internal modifications made to this engine. Change to larger stock MY2000 oil pan is the ONLY engine mod.
6) "Bearings, etc.. don't **** oil enough to which is implied, sure there's ancillary action, but not enough to **** oil at that rate.": - While Tom expressed his theory and has the years of work experience and schooling to credibly develop it, what is your basis for making your counter argument? How many have run a mechanical oil pressure gauge on a Viper and monitored the oil pressure at various RPM's? Could it be that all Vipers act in exactly the same way?
While Tom is a friend and this might come off as a bit defensive, I'm honestly looking to see if you can teach me something......
For background, car was purchased new by me and has currently has 18,000 miles. Stock except for above mentioned oil pan, 2002 OEM ss exhaust manifolds and Corsa 2.5" catback and have never had an engine problem beyond the typical gasket leaks, since repaired. The 65psi noted at 5500 RPM was steady and immediately returned to 80 as the RPM's dropped. Back to 5500, down to 65psi. Factory gauge never moved.
While of course you might be right, you challenge Tom at your own risk. Few here are as knowledgeable as he. Perhaps you need to do a search under his name to read up a bit.
****************************************************
Let dig in
1) What is the factual basis for your statement: "There's no way oil pressure should drop at higher rpm without indicating a problem"?
2) Either the pan is running out of oil: - No, 10 qts (2000 MY oil pan) exactly at the fill mark.
3) aeration (i.e. too much oil and the crank is whipping the oil into foam): - No, see above
4) clogged oil filter: - No, new K&N oil filter installed 300 miles ago
5) Some have added a high volume pump: - No, zero internal modifications made to this engine. Change to larger stock MY2000 oil pan is the ONLY engine mod.
6) "Bearings, etc.. don't **** oil enough to which is implied, sure there's ancillary action, but not enough to **** oil at that rate.": - While Tom expressed his theory and has the years of work experience and schooling to credibly develop it, what is your basis for making your counter argument? How many have run a mechanical oil pressure gauge on a Viper and monitored the oil pressure at various RPM's? Could it be that all Vipers act in exactly the same way?
While Tom is a friend and this might come off as a bit defensive, I'm honestly looking to see if you can teach me something......
For background, car was purchased new by me and has currently has 18,000 miles. Stock except for above mentioned oil pan, 2002 OEM ss exhaust manifolds and Corsa 2.5" catback and have never had an engine problem beyond the typical gasket leaks, since repaired. The 65psi noted at 5500 RPM was steady and immediately returned to 80 as the RPM's dropped. Back to 5500, down to 65psi. Factory gauge never moved.
2000_Black_RT10
Enthusiast
I'm not your friend too? Sheese.. nice guy.
Ok. I've been designing car stuff for quite some time, worked in several powertrain groups, including DCX at their R&D Centre, Highland Park, 2 years at Auburn Hills, and at the Featherstone Viper engineering group for about a year and I've landed at Ford (I left DCX shortly after the.. merger as they call it). I've even had the chance of working with the initial Hemi designer (Fred Shrimpton) many years ago who contracted at DCX during his retirement. I could [*******] all day long.. but what I'll stand behind is my comment that if oil pressure is dropping off this indicates there is a problem.
Do you think your K&N filter is ok? I've designed intake and air cleaner systems, of which I have a Patent in also (regarding resonators). It's not specifically related to this topic but I will also comment that K&N is not the best. For example - we tested K&N air filters and they failed the small particle test. Sure, this is not applicable, but K&N and many other aftermarket components have not endured the full capacity of testing requirments as an OEM component which would raise my suspicion.
I don't take this online stuff seriously nor do I feel like I want to describe my resume and there's no need to worry about being defensive. I'm here to learn also, nor am I an expert in computational fluid dynamics.
Carry on..
Ok. I've been designing car stuff for quite some time, worked in several powertrain groups, including DCX at their R&D Centre, Highland Park, 2 years at Auburn Hills, and at the Featherstone Viper engineering group for about a year and I've landed at Ford (I left DCX shortly after the.. merger as they call it). I've even had the chance of working with the initial Hemi designer (Fred Shrimpton) many years ago who contracted at DCX during his retirement. I could [*******] all day long.. but what I'll stand behind is my comment that if oil pressure is dropping off this indicates there is a problem.
Do you think your K&N filter is ok? I've designed intake and air cleaner systems, of which I have a Patent in also (regarding resonators). It's not specifically related to this topic but I will also comment that K&N is not the best. For example - we tested K&N air filters and they failed the small particle test. Sure, this is not applicable, but K&N and many other aftermarket components have not endured the full capacity of testing requirments as an OEM component which would raise my suspicion.
I don't take this online stuff seriously nor do I feel like I want to describe my resume and there's no need to worry about being defensive. I'm here to learn also, nor am I an expert in computational fluid dynamics.
Carry on..
Ron
Enthusiast
Mike,
Impressive experience and I enjoy the banter myself!
My K&N is an oil filter, not air. I prefer paper air filters for the same reason you mention regarding K&N air filters. I do send out my used oil for analysis and have been happy with the results using K&N. Read about oil filter flow rates and it seemed to indicate almost as good filtering as Mobil 1 filters with better flow rates, so that's the direction I went. The nut welded to the top (bottom) of the filter also helps.
Ron
Impressive experience and I enjoy the banter myself!
My K&N is an oil filter, not air. I prefer paper air filters for the same reason you mention regarding K&N air filters. I do send out my used oil for analysis and have been happy with the results using K&N. Read about oil filter flow rates and it seemed to indicate almost as good filtering as Mobil 1 filters with better flow rates, so that's the direction I went. The nut welded to the top (bottom) of the filter also helps.
Ron
2000_Black_RT10
Enthusiast
That's cool Ron,
The furthest thing I will imply is that I'm an expert, it's just suggesting some trouble shooting ideas. It's impossible for anyone to be an expert in all domains of vehicle design.
After a good high rev when you drop pressure, if you pull the dip stick out do see any bubbles on the dipstick?
The high flow filter may contribute to excess / more unrestricted flow which is allowing the pump to draw all the oil out of the pan. Have you ever encountered a drop in pressure, such as a scenerio of a steady 4000 rpm and going around a tight corner, such as an off / on ramp?
The only reason I made a friendly jab at Tom, F&L GoR regarding Post count was because of the comments in this Post below, no disrespect intended whatsoever. It'll take some time, I guess I'm just as new here as the rest of you all are to me.
http://www4.forum.viperclub.org/showflat.php?Cat=&Board=UBB14&Number=712580&......
The furthest thing I will imply is that I'm an expert, it's just suggesting some trouble shooting ideas. It's impossible for anyone to be an expert in all domains of vehicle design.
After a good high rev when you drop pressure, if you pull the dip stick out do see any bubbles on the dipstick?
The high flow filter may contribute to excess / more unrestricted flow which is allowing the pump to draw all the oil out of the pan. Have you ever encountered a drop in pressure, such as a scenerio of a steady 4000 rpm and going around a tight corner, such as an off / on ramp?
The only reason I made a friendly jab at Tom, F&L GoR regarding Post count was because of the comments in this Post below, no disrespect intended whatsoever. It'll take some time, I guess I'm just as new here as the rest of you all are to me.
http://www4.forum.viperclub.org/showflat.php?Cat=&Board=UBB14&Number=712580&......
Tom F&L GoR
Enthusiast
Ha, I'm safely in the top 75 now. Which only means I have thick enough skin to stay that long. =
Now that you're not a DCX-er, got any insight into the original selection of rear brakes? I'm drafting an article for the VCA magazine about them if you'd like to co-author. PM me an email and I'll send you a copy.
Now that you're not a DCX-er, got any insight into the original selection of rear brakes? I'm drafting an article for the VCA magazine about them if you'd like to co-author. PM me an email and I'll send you a copy.
V10SpeedLuvr
Enthusiast
20-25 at hot idle for me.
2000_Black_RT10
Enthusiast
Tom - I'll PM you my current work email address.
I was ******* with Gen 3 design support at the time. I do remember a conversation about brakes, and I know who to ask. This Post has inspired me to give a couple of the guys I worked with a call, plus I've been itchin' to tell them I own a Viper. Give me a day or 2, I'll track them down. I'll ask about oil pressure too.
I dug up this old pic, it's a car I got to play with on the weekend and I seem to remember they had a mocked up oil pan with swinging components, not that I'm implying anything.. but they asked me to put some miles on the car, how could I resist.
I was ******* with Gen 3 design support at the time. I do remember a conversation about brakes, and I know who to ask. This Post has inspired me to give a couple of the guys I worked with a call, plus I've been itchin' to tell them I own a Viper. Give me a day or 2, I'll track them down. I'll ask about oil pressure too.
I dug up this old pic, it's a car I got to play with on the weekend and I seem to remember they had a mocked up oil pan with swinging components, not that I'm implying anything.. but they asked me to put some miles on the car, how could I resist.
You must be registered for see images
Ron
Enthusiast
Mike,
Did check the oil level post OP dip observation and it was bubbleless - A lttle below full but once it sat for a few hours it was dead nuts on the full mark.
Knowing the early GENII's had an issue with sucking air on tight track corners (8 qt pan 96 ~ 99), I wired up a bright blue LED on my steering column piggy backed on the factory idiot light. Wanted to catch even a blip of low pressure in a track or under heavy braking. It has never gone on, except of course for the ignition on self test and recently when the idiot light sender puked. Also the reason why I went with the deeper GENII revised oil pan (10 qts, 00 ~ 02).
Had I never temp installed a mechanical OP gauge I would have never observed the dip, hence the thought "is it normal for all GENII Vipers?" No way to tell with the OEM garbage gauge.
Did check the oil level post OP dip observation and it was bubbleless - A lttle below full but once it sat for a few hours it was dead nuts on the full mark.
Knowing the early GENII's had an issue with sucking air on tight track corners (8 qt pan 96 ~ 99), I wired up a bright blue LED on my steering column piggy backed on the factory idiot light. Wanted to catch even a blip of low pressure in a track or under heavy braking. It has never gone on, except of course for the ignition on self test and recently when the idiot light sender puked. Also the reason why I went with the deeper GENII revised oil pan (10 qts, 00 ~ 02).
Had I never temp installed a mechanical OP gauge I would have never observed the dip, hence the thought "is it normal for all GENII Vipers?" No way to tell with the OEM garbage gauge.
99 R/T 10
Enthusiast
I just did a quick run, idle after warm up, 45-48 PSI. Balls out to 6000, goes up to 60 and is steady thru 6000. Just cruising, steady at 50 PSI.
Ron
Enthusiast
99 R/T 10,
Mechanical (capillary) gauge, aftermarket electronic or OEM Factory gauge? At what RPM did it reach 60psi?
Thanks
Mechanical (capillary) gauge, aftermarket electronic or OEM Factory gauge? At what RPM did it reach 60psi?
Thanks
99 R/T 10
Enthusiast
OEM. It looked like about 5000 RPM is when it reached 60 PSI. After driving for a couple of hours, idle pressure dropped to 40 PSI, but all others stayed the same.
