High oil pressure

[toolboxchev]

Originally Posted by jcblue

Noted on the zinc.. Thanks guys

Valvoline VR-1

Has it in it! Or Comp Cams break-in additive. Some of the others use a zinc replacement that does not do the same job, and is EPA O.K. (yuk)

[Aruba1]

Probably just me but I would want to know what oil pump was put in the motor. If it's a high volume oil pump, it will or may suck the oil pan dry unless of course a higher capacity pan was installed. How long ago was the motor rebuilt?

[jcblue]

The motor was rebuilt probably 5 years ago during the build of my truck.. Guy that did it knows his stuff and has a reputable shop..

[hardwaycooke]

Originally Posted by jcblue

Ok I went for a drive today and this is what the readings are.. 60 at startup cold.. Warm idle at 35-40. Cruising is anywhere in between those depending on how much I'm in the throttle. Thanks for all the responses

Just a note. When I built my 383 I ordered an oil pump with a couple different springs. I was a normal pressure pump but I accidentally left the high pressure spring in. Was pegging the stock gauge but when I primed it it was really good pressure too. Anyway, took the pump out, replaced it with the normal pressure spring, all's good. Just fyi.

[Aruba1]

Ok, for some reason I thought this was a new rebuilt. If it's been working fine all this time I would say have fun with it.

[Jrainman]

Originally Posted by hardwaycooke

Just a note. When I built my 383 I ordered an oil pump with a couple different springs. I was a normal pressure pump but I accidentally left the high pressure spring in. Was pegging the stock gauge but when I primed it it was really good pressure too. Anyway, took the pump out, replaced it with the normal pressure spring, all's good. Just fyi.

You are Correct Sir , it is very doubtful his engine builder put a high flow oil pump in ,being it was built with only a slightly larger cam ,

the spring and ball operate the pressure relief in the oil pump this is how the pressure is made to keep constant , high oil pressure with in reason is better for your bearings

bypass valves in oil filters opens at 10-12 pounds , remember your filter is on the return side of the oil flow , bypass valve operation is for the filter it self if the filter becomes restricted (dirty) at 10-12 pounds it will by pass dirty oil is better then NO OIL , also on a very cold starts some oils might be to thick and again the bypass valve will do its job.

I added the by pass valve in the oil filter operation for a reason , lets say the pressure relief spring in the oil pumps fails or hangs up , to check for this failure all you have to do is drop your oil filter if your filter look expanded or very mangled you know your oil pump pressure relief valve has had a failure.

if your engine at idles and oil PSI is below 25 psi its getting worn out.

[DT1]

When I rebuilt my 350 the only mods were a mild RV cam and high volume oil pump. The oil pressure was also very high. It was almost pegged at normal cruising speed. It concerned me so much, I changed the pump out for a stock one. I made no difference in pressure. That was five years and 50K miles ago. The only time I get concerned now is when I look at the gauges and mistake oil for the Temp gauge. A little adrenalin rush at first but then I come back to my senses.

[cleszkie]

There are two main downsides to running a high pressure/high volume pump.

1) There is more stress on the oil pump shaft and coupler that goes between the distributor and pump. Especially during cold start ups when oil id thick. If you are still running a plastic coupler, the added stress can break it and leave you with zero oil pressure in the blink of an eye.

2) If you heads have not been modified to allow for quicker drainage of oil back into the pan, too much oil will accumulate under your valve covers, and your oil pan level will be low. Worst case is when the level in pan gets below the pick up and you start sucking air.

[mike16]

Originally Posted by cleszkie

There are two main downsides to running a high pressure/high volume pump.

1) There is more stress on the oil pump shaft and coupler that goes between the distributor and pump. Especially during cold start ups when oil id thick. If you are still running a plastic coupler, the added stress can break it and leave you with zero oil pressure in the blink of an eye.

2) If you heads have not been modified to allow for quicker drainage of oil back into the pan, too much oil will accumulate under your valve covers, and your oil pan level will be low. Worst case is when the level in pan gets below the pick up and you start sucking air.

my replacement coupler came attached to my new hd shaft. still I agree you do not need such high oil pressure. but its good insurance anyway.

I do have the hi volume hi pressure ol pump, it was a mistake to go that extreame. I am very carefull, even on hot days in AZ and more so on cold days to drop the warm up rpm's as soon as I can to avoid having the guage blow out of my instrument pannel.

but I dont have a problem with low oil level due to its being all up in the heads. I've had this oil pump installed for over 5 years and other than warm up oil pressure readings no problems at all. even at idle in PHX in August I get good steady pressure readings.

I use a 50/50 mix of mobile 1 and streight 30 wt and the two quart spin on oil filter. no problems coming or going. Truck actualy stoped using oil too. go figure.

[Rich72C10]

Sorry for the dug up of a old thread... but hate to start a new one.

Okay, so my SBC 350 has been rebuilt and while I know the oil pump was replaced, not sure if my brother put in a high performance pump in (keep forgetting to ask). The other day I picked up my truck down from the transmission shop (to fixed two leaks) and got on I35 North straight away from a coldish startup. As I was up to highway speed in the slow lane (70 mph) @ a bit over 2500 rpms I noticed I was pegged H or pretty much pegged. I kind of freaked out so I backed off to about ~60. I am sure that made people behind me happy, not in Texas I tell you. The slow lane is the new fast lane in Texas! LOL

So I did a controlled test this morning. Started her up, cold (for Texas) and the oil pressure stays around a hair over the 2/3 mark. Let her choke up (bit over 1k rpms) and then pop the gas after a few minutes down to ~600 rpms. Waited roughly 5 minutes, which the temp reached normal (at the 1/4 mark). Still roughly at the 2/3 mark on the oil pressure gauge. This is all idle.

Took a ride around a few blocks, gave her WOT where I could but not going real fast of course since I am in our neighborhood. She went above the 3/4 mark but did not touch H on the oil pressure gauge. Temp steady at a hair over 1/4 mark.

Near the end of my drive (no more than 1 mile) as I am making my turns/slowing down the oil pressure gauge starts to settle to 1/2 mark. As I speed up I reach 2/3 mark. Then back and fourth 1/2 to 3/4 in neighborhood driving (20~30, full stops/slow turns).

Get back home, pull into garage, put her into Park. Settles on a solid 1/2 mark. Gun her slightly, gauge moves towards 2/3 and drifts back and settles on 1/2 mark. She is nice and warmed up now.

I have put in a order for Valvoline VR-1, regardless of anything that seems like a good idea for a SBC. I am still under 1k miles on the rebuild and I just changed the oil last weekend. I want to say my brother did it twice before me (once because the carb did something odd at the beginning and backed up a ton of gas into the engine). There is no odd ticking/knocking/etc. She loves to drive and seems to want me to give her the gas and get a move on ;-)

So back to my freakout when I got on I35 and I looked down to the gauge that appeared pegged to H - do I have something to worry about here with my oil pressure?

Edit: brother says to long ago, can't remember. He only knows the pump is new. Grrr. I told him that is why I wanted him to save all the parts receipts. Dork. Though I explained all the above to him in my call this morning, he says nothing sounds un-normal. Guess I am going with that :-)

[Steeveedee]

Your numbers look fine. The real problems come when guys fiddle with the pressure relief spring believing that more pressure is better. I've seen oil filters blow out at the drag strip. My truck's engine (BBC) has about 100k on the rebuild and still pegs the gauge cold. It idles at ~mid gage and runs up to H when running down the road. It was that way when I got it, so I don't worry about it. I will eventually get an 80 PSI medium-large truck gage to put in it, simply because I like to know what the actual values are.

[Rich72C10]

Thank you so much Steeveedee - great to have someone follow up that I trust around here. Not that I don't trust my brother, there is no problem with double verification! Ha!