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Hi everyone! I'm pretty new to the site but I've been lurking for a while. Have a question about oil pressure in a mildly modified 396(+.030) BBC. I'm reading about 80 PSI when starting cold and this goes up to ~90 when I hit the gas. After it warms up reads about 60 idling but goes back up to 80 under any load. My old Chilton says these engines should run around 30-60. Is my oil pressure too high and if so what should I do about it? :confused:
Thanks,
Chris
thats higher than I like it. the problem with that much pressure is the oil don't stay around long enough to lub. anything. you need a hi volumn pump, not a hi pressure one. that used to be the way we thought it should be. :HMMM: :cool:Quote:
Originally posted by skids72
Hi everyone! I'm pretty new to the site but I've been lurking for a while. Have a question about oil pressure in a mildly modified 396(+.030) BBC. I'm reading about 80 PSI when starting cold and this goes up to ~90 when I hit the gas. After it warms up reads about 60 idling but goes back up to 80 under any load. My old Chilton says these engines should run around 30-60. Is my oil pressure too high and if so what should I do about it? :confused:
Thanks,
Chris
What happens when you have to high an oil pressure is the small dirt particles that are not caught by the oil filter are pressed in to the soft bearing material.Quote:
Originally posted by skids72
Hi everyone! I'm pretty new to the site but I've been lurking for a while. Have a question about oil pressure in a mildly modified 396(+.030) BBC. I'm reading about 80 PSI when starting cold and this goes up to ~90 when I hit the gas. After it warms up reads about 60 idling but goes back up to 80 under any load. My old Chilton says these engines should run around 30-60. Is my oil pressure too high and if so what should I do about it? :confused:
Thanks,
Chris
Thanks, everyone. I had a feeling it was really high. Supposedly, the engine was newly rebuilt with ~500 miles on it before I purchased the car. I've put about another 750 on it myself. I'm running 10W30 synthetic (Mobil 1) as suggested by the salty old car emissions guy. Should I go with petroleum of say 5W30? Sounds like the pressure will come down after more miles?
The proper course of action would be to pull the engine and install a high volume pump? I'm not very well equipped here to do that myself but would you say it is worth the $$$ to have this done as opposed to hoping it will come down over time (I think I know the answer to this one). Are there other things that could be causing the high pressure than the pump itself?
Many thanks for all your insights,
Chris
I would never run synthetic oil with this new an engine.The rings will never (seat).One area that was overlooked was the gauge and the sending unit.I would try another gauge and sending unit before I would go dropping the oil pan.Quote:
Originally posted by skids72
Thanks, everyone. I had a feeling it was really high. Supposedly, the engine was newly rebuilt with ~500 miles on it before I purchased the car. I've put about another 750 on it myself. I'm running 10W30 synthetic (Mobil 1) as suggested by the salty old car emissions guy. Should I go with petroleum of say 5W30? Sounds like the pressure will come down after more miles?
The proper course of action would be to pull the engine and install a high volume pump? I'm not very well equipped here to do that myself but would you say it is worth the $$$ to have this done as opposed to hoping it will come down over time (I think I know the answer to this one). Are there other things that could be causing the high pressure than the pump itself?
Many thanks for all your insights,
Chris
Thanks, Erik...
I'll give that a try (real oil then another gauge) and let you all know what happens. This will probably be a few weeks out at least (recovering from a shoulder injury) :(
Quote:
Originally posted by erik erikson
I would never run synthetic oil with this new an engine.The rings will never (seat).One area that was overlooked was the gauge and the sending unit.I would try another gauge and sending unit before I would go dropping the oil pan.
"I would never run synthetic oil with this new an engine.The rings will never (seat)."
wrong!!!you can do whatever you want skids72, but that statrment is not true. new cars come with it in them every day. the hi doller ones anyway. . :HMMM:
Synthetic Motor Oil can be used during break-in trouble free. In fact, vehicles such as Dodge Viper and Chevrolet Corvette come factory filled with synthetic oil.
Since most new vehicles come filled with petroleum oil, it only makes good sense to change to synthetic at the first scheduled oil change interval. New engine components generate high levels of wear metals and can contain contaminants from assembly. By allowing the engine to operate with the petroleum oil until the first oil/filter change interval, the wear metals and contaminants are removed prior to installing synthetic oil. If its not useing oil then the rings has seated. whether the rings are seated or not has nothing to do with the oil pressure. :cool:
It really depends on the ring material.If they are cast rings this might be o.k. but on a moly ring or a plasma moly,or any type plasma ceramic ring you will never get the rings to seat because the surface of the ring is very hard it will take some time to wear in.Also the synthetic motor oil is so slick it is more able to pass by the rings.If you want to run the synthetic oil use only a few qts.Quote:
Originally posted by lt1s10
"I would never run synthetic oil with this new an engine.The rings will never (seat)."
wrong!!!you can do whatever you want skids72, but that statrment is not true. new cars come with it in them every day. the hi doller ones anyway. . :HMMM:
Yes,I know that the rings being seated has nothing to do with the oil pressure.Who said they did?Quote:
Originally posted by lt1s10
Synthetic Motor Oil can be used during break-in trouble free. In fact, vehicles such as Dodge Viper and Chevrolet Corvette come factory filled with synthetic oil.
Since most new vehicles come filled with petroleum oil, it only makes good sense to change to synthetic at the first scheduled oil change interval. New engine components generate high levels of wear metals and can contain contaminants from assembly. By allowing the engine to operate with the petroleum oil until the first oil/filter change interval, the wear metals and contaminants are removed prior to installing synthetic oil. If its not useing oil then the rings has seated. whether the rings are seated or not has nothing to do with the oil pressure. :cool:
On this synthetic vs. petroleum controversy all I can add is that I haven't been burning any oil so I think the rings are seated. Regardless, I'll try a lower weight oil and see if it has any effect on the pressure.
Many thanks for all contributions
Quote:
Originally posted by erik erikson
Yes,I know that the rings being seated has nothing to do with the oil pressure.Who said they did?
Originally posted by erik erikson
"I would never run synthetic oil with this new an engine.The rings will never (seat)."
you brought the ring thing into it. I was talking about oil pressure. his rings is seated and you have him changing oil because you say his rings wan't never seat with Synthetic oil in it. thats not true and I guess his car proves it.
Another thought.... what if I'm slightly overfilled? I used 5 qts last time I changed oil and filter (again, this should be right according to chilton) but I'm a little over the full mark on the stick. Would this push up the pressure?
thanks again,
Chris
Thanks, Denny
But supposing it is actually overfull, would that make for high pressure?
did you say if you were using a mechanial guage?
Here are a couple of web-sites from oil manufactuers and what they say about using synthetic oil on a new engine.www.redlineoil.com check out what they say in their 4th paragraph.Also www.coximport.com They have a nice section in the 6th. paragraph.Also notice they recommend a long break-in for "hard piston rings"These are just a couple of oil companies that don't recommend using their own synthetic oil for break-in.Quote:
Originally posted by lt1s10
"I would never run synthetic oil with this new an engine.The rings will never (seat)."
wrong!!!you can do whatever you want skids72, but that statrment is not true. new cars come with it in them every day. the hi doller ones anyway. . :HMMM:
Quote:
Originally posted by erik erikson
Here are a couple of web-sites from oil manufactuers and what they say about using synthetic oil on a new engine.www.redlineoil.com check out what they say in their 4th paragraph.Also www.coximport.com They have a nice section in the 6th. paragraph.Also notice they recommend a long break-in for "hard piston rings"These are just a couple of oil companies that don't recommend using their own synthetic oil for break-in.
you look long enough you can find anything you want. you claim to be in the high performance bus. and one thing all of them agree on is, its the best oil for racing motors, blower motor, or any motor that gonna be run in the extreme hot or cold, and I haven't heard you say any thing good about it at all. I've put it in new motors,(more than one time) it comes in new cars and I didn't have a problem with it and will continue to use it. if those cos. you were talking don't recomend their own oil, thats their problem.
It sure is funny you make a post and then run off."If I look long enough I can find anything you want?"I just gave you info. from two major aftermarket oil manufacturest .The synthetic oil is great after you do all the break -in.Yes, you will make a little more power because of the reduction in friction.I see you claim you are a mechanic.You are not an engine builder.If you countinue to do this you will get bit.Good Luck.Quote:
Originally posted by lt1s10
you look long enough you can find anything you want. you claim to be in the high performance bus. and one thing all of them agree on is, its the best oil for racing motors, blower motor, or any motor that gonna be run in the extreme hot or cold, and I haven't heard you say any thing good about it at all. I've put it in new motors,(more than one time) it comes in new cars and I didn't have a problem with it and will continue to use it. if those cos. you were talking don't recomend their own oil, thats their problem.
build enough of them and you gonna get bit with reg. oil to. I havent seen a motor that the rings didn't seat in a long time anyway, and if you have, maybe you need to change to a dif. oil. its not a problem around here anymore.Quote:
Originally posted by erik erikson
It sure is funny you make a post and then run off."If I look long enough I can find anything you want?"I just gave you info. from two major aftermarket oil manufacturest .The synthetic oil is great after you do all the break -in.Yes, you will make a little more power because of the reduction in friction.I see you claim you are a mechanic.You are not an engine builder.If you countinue to do this you will get bit.Good Luck.
The point I was trying to make was not to intrduce the syn. oil to early.I have used some of the hard faced rings and after 20 hard pulls on the dyno they where not seated with reg. oil and I am sure it would have taken much longer with the syn. oil.It really depends on the ring material and the bore finish and angle of the finish.Yes,you are right you will get bit with the regular oil too.Maybe I do need to try a couple different brands.Quote:
Originally posted by lt1s10
build enough of them and you gonna get bit with reg. oil to. I havent seen a motor that the rings didn't seat in a long time anyway, and if you have, maybe you need to change to a dif. oil. its not a problem around here anymore.
I'll meet you 1/2 way on this one, but don't get used to it. the best way to do this would be to put reg. oil in the motor first,(new motor) run the break in miles, and if you don't have a problem , then put the syn. oil in. you are invited to have a beer with me and corvette. no, I take that back, I will never be in the same room with both of you at the sametime. :HMMM: :whacked:Quote:
Originally posted by erik erikson
The point I was trying to make was not to intrduce the syn. oil to early.I have used some of the hard faced rings and after 20 hard pulls on the dyno they where not seated with reg. oil and I am sure it would have taken much longer with the syn. oil.It really depends on the ring material and the bore finish and angle of the finish.Yes,you are right you will get bit with the regular oil too.Maybe I do need to try a couple different brands.
Some people would kill fot that problem. If it trobles you go to a 10/30 or 5/30 oil.
I run 90 psi at idle and 150-160 cold 60-120 psi hot...