The oil pressure is the result from the oil pump from Katech. We had a oil pressure problem and were running 15 PSI at idle with the LS 7 which I was told that it was the minimum pressure required from Chevrolet, we seized the motor, we were running around 45 to 55 psi with the stock pump at higher RPM, so the problem was when it idled. I contacted Katech and this is what they recommended, their high volume pump. It had just come out, and talking to them, they said they developed the high volume pump due to the low idle pressures when running the oil cooler and dry sump system. We did discuss all the routing and size of the lines with Katech also. I am not sure about if you have too much pressure, I will have to get back with Katech and ask them unless Fran knows this answer. I have been told by the original motor builder that the oil temperature should not exceed 240 degrees or the oil will start to break down. I do not know if this is true or not. I have found the problem with the automotive industry is the amount of wrong info you are given, so all I can do is talk to the people in technical departments, explain what is going on and go with what they recommend. I can say this pump is what is being run in the Katech engine they build for the Corvette race team. I can also tell you from experience that 15 PSI at idle is not enough pressure for the exact set up I had. Randy I agree all you need to do is provide oil between the surfaces, not flood them. I have found that oil weight is a direct effect to oil pressure. The motor builder we used here in Atlanta said to run 20W-50 VR1 Racing oil which I do. I will need to check out if we need to change weight oil. I think this discussion on oil is very helpful to prevent oil failure issues for everyone before it happens, it gets very expensive, like I have already experienced, we had to replace everything in the motor except the block and bare heads, and intake.
Dry Sump Tank
- Thread starter slc4yos
- Start date
This has been mentioned before: The amount of zinc in the motor oil during initial break in is critical, and engine oils contain less zinc than they used to.
Lifter & cam failures due to oil reformulation.
Galvanic corrosion with dissimilar metals (block, washers and bolts).
This stuff is expensive enough w/o losing a motor.
Lifter & cam failures due to oil reformulation.
Galvanic corrosion with dissimilar metals (block, washers and bolts).
This stuff is expensive enough w/o losing a motor.
I have talked to my motor builder Lamar Walden Automotive. Lamar was recommended to me by everyone I asked when I was looking for a motor builder here in Atlanta. I asked him the following questions;
1. Is there a problem with running a high oil pressure such as 100 psi and does this cause a premature wear of parts or failure of the engine?
Answer: He said he has never heard of a problem with a LS 7 failing due to high oil pressure or heard of or seen any problems due to high oil pressure.
2. What is the optimum oil pressure you want to see?
Answer: At idle he wants to see 50 to 55psi and at higher RPM's 65 to 70 psi. He discussed the LS7 is prone to crank bearing problems due to low oil pressure and usually occurs at idle ( the same thing Katech told me). He uses a push rod reswtricted at the top of the rod to cause more oil pressure at the bottom end to help the crank bearings.
3. What is the temperature range we should be shooting for with the oil?
Answer: He likes to see between 180 and 200 degrees, the oil should also run around 30 degrees hotter than the water temps when running the engine hard. He does not like to see the oil run much less than 175 for any period of time. The reason is the oil needs to get to temperature to remove the condensation of water that accumulates.
4. How do I adjust the oil pressure to get it where it needs to be?
Answer: Oil pressure is directly related to oil viscosity, he wants me to run the 20W-50 oil to help break in the motor.It takes longer to break in a LS7 engine than the other LS motors, it should take around 3000 miles to seat the rings. Synthetic oil will not seat rings. Also I can run 10W-30 to drop the pressure which will drop between 15 to 30 lbs. once it is broke in run a 5W-30 synthetic which should get the pressure where it needs to be.
He also told me he has talked to Chevrolet and they are not recommending a stud for the heads any more, they want bolts instead. The problem is they are seeing the cylinder distort slightly with the studs and getting a slight blow by when the piston is at the top of the stroke.
I have placed a call to Jason Harding at Katech to talk to him about the same info, and emailed Valvoline and asked about the temperature ranges they are recommending. I will post the results when I get them.
1. Is there a problem with running a high oil pressure such as 100 psi and does this cause a premature wear of parts or failure of the engine?
Answer: He said he has never heard of a problem with a LS 7 failing due to high oil pressure or heard of or seen any problems due to high oil pressure.
2. What is the optimum oil pressure you want to see?
Answer: At idle he wants to see 50 to 55psi and at higher RPM's 65 to 70 psi. He discussed the LS7 is prone to crank bearing problems due to low oil pressure and usually occurs at idle ( the same thing Katech told me). He uses a push rod reswtricted at the top of the rod to cause more oil pressure at the bottom end to help the crank bearings.
3. What is the temperature range we should be shooting for with the oil?
Answer: He likes to see between 180 and 200 degrees, the oil should also run around 30 degrees hotter than the water temps when running the engine hard. He does not like to see the oil run much less than 175 for any period of time. The reason is the oil needs to get to temperature to remove the condensation of water that accumulates.
4. How do I adjust the oil pressure to get it where it needs to be?
Answer: Oil pressure is directly related to oil viscosity, he wants me to run the 20W-50 oil to help break in the motor.It takes longer to break in a LS7 engine than the other LS motors, it should take around 3000 miles to seat the rings. Synthetic oil will not seat rings. Also I can run 10W-30 to drop the pressure which will drop between 15 to 30 lbs. once it is broke in run a 5W-30 synthetic which should get the pressure where it needs to be.
He also told me he has talked to Chevrolet and they are not recommending a stud for the heads any more, they want bolts instead. The problem is they are seeing the cylinder distort slightly with the studs and getting a slight blow by when the piston is at the top of the stroke.
I have placed a call to Jason Harding at Katech to talk to him about the same info, and emailed Valvoline and asked about the temperature ranges they are recommending. I will post the results when I get them.
I have had the following response to my question from Valvoline, I asked,
Question: What should be the operating temperature for a LS7 engine minimum and maximum, is there a difference with a street car vs a race car, also is there a maximum oil pressure for a LS7 engine and can high oil pressure do damage to bearings or other components and what would that pressure be?
Answer: normal operating temperatures for GM LS engines are between 160 and 230 degrees F. These operating temperatures should remain the same in both street and race applications. Conventional engine oils can withstand temperatures up to 400 degrees F, and synthetics above 500 degrees F. Should your engine ever produce oil temperatures above 270 degrees F this could effect other system components in the engine and may result in engine failure.
As for maximum oil pressure, your engine should never run more than 60psi during start up or idle. If you see higher pressures than this, the wrong viscosity grade of oil may be the source of the increase. We would recommend using a lighter viscosity grade of oil.
I am getting a feel on where your engine pressure should be and how to adjust it, so when someone says what weight oil should I run in my car, now I know how to adjust it until your oil pressure is correct at idle
Question: What should be the operating temperature for a LS7 engine minimum and maximum, is there a difference with a street car vs a race car, also is there a maximum oil pressure for a LS7 engine and can high oil pressure do damage to bearings or other components and what would that pressure be?
Answer: normal operating temperatures for GM LS engines are between 160 and 230 degrees F. These operating temperatures should remain the same in both street and race applications. Conventional engine oils can withstand temperatures up to 400 degrees F, and synthetics above 500 degrees F. Should your engine ever produce oil temperatures above 270 degrees F this could effect other system components in the engine and may result in engine failure.
As for maximum oil pressure, your engine should never run more than 60psi during start up or idle. If you see higher pressures than this, the wrong viscosity grade of oil may be the source of the increase. We would recommend using a lighter viscosity grade of oil.
I am getting a feel on where your engine pressure should be and how to adjust it, so when someone says what weight oil should I run in my car, now I know how to adjust it until your oil pressure is correct at idle
While I'm not convinced of the need for higher oil pressure unless for some reason there is enough restriction so the last bearing see's very little of the head pressure from the pump. I am not aware of this issue with the LSx engines.
Oil temps -
I have run a sustained 300 degrees with Mobil-1 in my SCCA American Sedan Camaro and never had an oil related failure. I ran 10w30 with no issues. That car would get it's neck rung for an hour straight in a number of races. Sprint races only 30-45 minutes.
Water temp would be 220-230 with a 20# cap.
Oil temps -
I have run a sustained 300 degrees with Mobil-1 in my SCCA American Sedan Camaro and never had an oil related failure. I ran 10w30 with no issues. That car would get it's neck rung for an hour straight in a number of races. Sprint races only 30-45 minutes.
Water temp would be 220-230 with a 20# cap.
Sorry to hijack but is there a build thread or any info on Craig's SLC anywhere? Looks like an awesome build!Stick it between the beams - but you have to wedge it in there and I don't know if I'd feel comfortable having the tank smashed up into the beams like that like in Craig's car
Ken Roberts
Supporter
16" tall by 9" round is the size of the 3 gal tank Peterson tank.
The Z06 tank I'm going to attempt to use is 22" tall by 6" round. I cut it down by 2".
Ken Roberts
Supporter
I plan to place it outboard on the passenger side. I wouldn't recommend a 6" diameter tank though unless you do a piggyback add on as the volume of oil held in a 6' tank is only 8 liters. Mine is increased to 10 liters.
Also the 6" diameter tanks are probably too tall. They are 24" tall. I cutout a couple of inches in mine so that it's 22" tall. I like the fact that mine can be placed in tight then the piggyback section can be welded on in a ideal angle. It's a lot of fabrication though but I enjoy the challenge.
I would like to thank you guys for the oil pressure questions which started my quest for info. I changed the oil and put in 10W30, my pressure when it finally got hot 185 deg oil temp, the pressure dropped to 63 psi idling. When I go to the synthetic I know I can get it down below 60 psi but I have to wait till I get it broke in. I appreciate all the input it helped me from having future problems.
