Twin turbo oil temps/hot idle pressure
11-10-2014, 01:35 PM
#22
For anyone else who doesn't want to spend $200 on the improved racing piece.
http://pages.ebay.com/link/?nav=item...d=131256125015
http://pages.ebay.com/link/?nav=item...d=131256125015
11-10-2014, 03:32 PM
#25
considering you are in TX.... I would still look at the ImprovedRacing adapter as it has a thermostat built into it even though it is more expensive.... and run minimum...1 large quality oil cooler.... if that doesn't regulate the temps.... run a 2nd one.
What size is your radiator and what fan do you run?
What size is your radiator and what fan do you run?
11-10-2014, 05:27 PM
#26
considering you are in TX.... I would still look at the ImprovedRacing adapter as it has a thermostat built into it even though it is more expensive.... and run minimum...1 large quality oil cooler.... if that doesn't regulate the temps.... run a 2nd one. What size is your radiator and what fan do you run?
11-10-2014, 07:50 PM
#27
Just went through a few logs and my motor does the same thing (drop in oil pressure) in between shifts (5-9psi) but I'm a 6-spd so that makes sense to me as letting off the throttle would do such a thing. What trans do you have? at any rate the fact that you drop pressure when RPM increases is something to be worried about IMO..
11-11-2014, 02:33 AM
#28
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Having had a oil temp sensor on mine for a bit now..
Under most driving conditions, oil temp almost tracks coolant temp.
At a recent track I was at, each outing around 120s for me, just under 2 mile lap.
Wide range of speeds from 30mh to 145mph at the finish.
Oil temps at start of run around 185degF ( same as coolant )
Oil temps at end of run around 230degF, Coolant remained around 190degF
For a decent oil, this is not enough to cause any oil pressure worries or concerns.
I have no oil cooler, and I am running a remote oil filter since turbos were done, Autokraft pan, Melling HV pump with the softer spring
That said, oil pressure on my engine is pretty **** and has been all year, gradually getting worse. Will be pulling it apart over the next few weeks though. It's been together for near 4 years.
I've seen as low as 15-20psi at idle, and 35-40psi at high rpm's
More strangely, oil pressure will literally fall say 3-4psi if I open the throttle. Cruising along, any rpm, no real load on engine...open throttle and oil pressure drops. At first I thought it an electrical issue, but ecu logging does same as mechanical gauge.
Even when racing, in between gearchanges as load is removed then re-applied, oil pressure rises then falls. It's weird !
Under most driving conditions, oil temp almost tracks coolant temp.
At a recent track I was at, each outing around 120s for me, just under 2 mile lap.
Wide range of speeds from 30mh to 145mph at the finish.
Oil temps at start of run around 185degF ( same as coolant )
Oil temps at end of run around 230degF, Coolant remained around 190degF
For a decent oil, this is not enough to cause any oil pressure worries or concerns.
I have no oil cooler, and I am running a remote oil filter since turbos were done, Autokraft pan, Melling HV pump with the softer spring
That said, oil pressure on my engine is pretty **** and has been all year, gradually getting worse. Will be pulling it apart over the next few weeks though. It's been together for near 4 years.
I've seen as low as 15-20psi at idle, and 35-40psi at high rpm's
More strangely, oil pressure will literally fall say 3-4psi if I open the throttle. Cruising along, any rpm, no real load on engine...open throttle and oil pressure drops. At first I thought it an electrical issue, but ecu logging does same as mechanical gauge.
Even when racing, in between gearchanges as load is removed then re-applied, oil pressure rises then falls. It's weird !
11-11-2014, 04:27 AM
#29
9 Second Club
Just went through a few logs and my motor does the same thing (drop in oil pressure) in between shifts (5-9psi) but I'm a 6-spd so that makes sense to me as letting off the throttle would do such a thing. What trans do you have? at any rate the fact that you drop pressure when RPM increases is something to be worried about IMO..
Mine is a rise in pressure as soon as the throttle is closed, and a fall when it is opened again.
Even at say 1500rpm when cruising, the same pattern occurs, the engine would have almost no load at this point, although pressure variation is smaller.
I'm T56, and yes I'm aware my oil pressure is not good.
Strange thing is, when I first built it, when cold oil pressure was easily 70psi or so, warm pressure 50-60psi when revving.
Over a relatively short period of time this fell to a fairly low level, and then over the last 2 years or so it's slowly got worse.
As to what the actual cause is, no idea. I had problems with cam bearings walking before, but when I rebuilt last time I pinned the bearings. Same block though.
Start of this year seen me move to two turbos from the YSi, so that would have increased oil demand somewhat from the pump. Although wasnt logging oil pressure prior to that, so dont have any hard data to refer back to other than memory from the mechanical gauge.
Have a new block sitting, will rebuild, also going solid roller for some nice rpm's. Hopefully no major issues inside and I can just swap everything over to the new block.
11-11-2014, 05:25 AM
#30
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I wonder if additional baffles or a better oil pan would help
sounds like the pickup might be sucking air
11-11-2014, 06:29 AM
#31
Mine isnt a drop though. Mine is a rise in pressure as soon as the throttle is closed, and a fall when it is opened again. Even at say 1500rpm when cruising, the same pattern occurs, the engine would have almost no load at this point, although pressure variation is smaller. I'm T56, and yes I'm aware my oil pressure is not good. Strange thing is, when I first built it, when cold oil pressure was easily 70psi or so, warm pressure 50-60psi when revving. Over a relatively short period of time this fell to a fairly low level, and then over the last 2 years or so it's slowly got worse. As to what the actual cause is, no idea. I had problems with cam bearings walking before, but when I rebuilt last time I pinned the bearings. Same block though. Start of this year seen me move to two turbos from the YSi, so that would have increased oil demand somewhat from the pump. Although wasnt logging oil pressure prior to that, so dont have any hard data to refer back to other than memory from the mechanical gauge. Have a new block sitting, will rebuild, also going solid roller for some nice rpm's. Hopefully no major issues inside and I can just swap everything over to the new block.
In your previous post you clearly stated you have a 3-4psi drop when you open the throttle. As far as the pressure building after the throttle is closed and then dropping mine does the same thing.. Not saying it's right. My data looked the same steady climb in oil pressure with RPM, I let off pressure spikes and drops A LOT like 30 psi or so. It then soon climbs back to normal operating levels. I will say that I also had my cam bearings walk on this motor. It was so bad that they where spinning in the tunnel. I had to get oversized (OD) bearing for it on the rebuild.
11-11-2014, 06:44 AM
#32
I don't think you should sweat a small drop in pressure. As long as there is enough pressure to keep the crank riding on a oil wedge why does it matter? 10psi per 1000 rpm is considered "enough" pressure. So if your above 40psi by 4k, 50psi by 5k etc... There is enough pressure to keep the crank from contacting the bearing.
If your not road racing the car for extended periods, or reving it high for extended periods... I'd just shim up the pressure relief spring with a few washers and get the coolant temps down with a better fan/shroud setup. Also try a thicker oil if you want more pressure at higher operating temps.
What oil pan are you running?
If your not road racing the car for extended periods, or reving it high for extended periods... I'd just shim up the pressure relief spring with a few washers and get the coolant temps down with a better fan/shroud setup. Also try a thicker oil if you want more pressure at higher operating temps.
What oil pan are you running?
Last edited by Forcefed86; 11-11-2014 at 06:55 AM.
11-11-2014, 06:59 AM
#33
I agree with the pressures and A drop in PSI in between shifts makes sense to me. My concern is low hot idle psi. I'm assuming it's becuase of excess oil temps. Never knew about shimming the pressure relief. I would love a shroud for the car but my coolant temps are not an issue. They rarely gets over 210 degrees. Is there something else I'm missing as far coolant/oil temp relationship goes? I'm running the LS2/3 pan unfortunately. I need the clearance it provides but hate the capacity and lack of baffling
11-11-2014, 08:08 AM
#34
In general the cooler your coolant temps, the cooler your oil temps. Coolant temps also have a direct effect on detonation threshold. 210* is HOT for a turbo car IMO. I like to see under 180 before a run. I do allow my coolant to hit 210 or more cruising to and from the track to boil off the moisture in the oil etc... But at the track the Taurus fan goes on high and 180* or less before I make a boosted pass.
If your over 10-15psi at idle your fine IMO. My LS stuff has always been 38-40 once at peak coolant temps after long cruises at idle. More than enough pressure. I wouldn’t worry about yours.
I’m not familiar with that pan. I’d assume you could run at least 1qt over the full mark on your dipstick as well. On the LS1 pan car running, jacked, level… I added oil until it started to trickle out of the turbo oil return line. 5.5qts is the capacity listed for the ls1 pan. I was able to add 8qts of oil before it trickled out of the return line. Full 2.5 qts over the suggested amount. So I’d assume you could easily run at least 1qt overfull for a little more capacity. Very common for guys to run 1.5-2qts over full on the ls1 pan anyway.
My main concern is the pan pickup being uncovered in “spirited” driving. I had issues with this on my LS1 pan. I’d suggest modifying the pickup (move it to the rear of the sump) or installing Improved Racings baffle setup to help with oil control. Put 2 standard thickness washers behind the oil pump relief spring. (or order a higher pressure spring if you want to do it correctly).
1.) Get some sort of oil control to keep pressures constant.
2.) Get those coolant temps down
3.) Shim or re-spring the oil pump
4.) Run syn oil to deal with the higher temps (higher weight if you want more pressure at temp)
If your over 10-15psi at idle your fine IMO. My LS stuff has always been 38-40 once at peak coolant temps after long cruises at idle. More than enough pressure. I wouldn’t worry about yours.
I’m not familiar with that pan. I’d assume you could run at least 1qt over the full mark on your dipstick as well. On the LS1 pan car running, jacked, level… I added oil until it started to trickle out of the turbo oil return line. 5.5qts is the capacity listed for the ls1 pan. I was able to add 8qts of oil before it trickled out of the return line. Full 2.5 qts over the suggested amount. So I’d assume you could easily run at least 1qt overfull for a little more capacity. Very common for guys to run 1.5-2qts over full on the ls1 pan anyway.
My main concern is the pan pickup being uncovered in “spirited” driving. I had issues with this on my LS1 pan. I’d suggest modifying the pickup (move it to the rear of the sump) or installing Improved Racings baffle setup to help with oil control. Put 2 standard thickness washers behind the oil pump relief spring. (or order a higher pressure spring if you want to do it correctly).
1.) Get some sort of oil control to keep pressures constant.
2.) Get those coolant temps down
3.) Shim or re-spring the oil pump
4.) Run syn oil to deal with the higher temps (higher weight if you want more pressure at temp)
11-11-2014, 08:46 AM
#35
In general the cooler your coolant temps, the cooler your oil temps. Coolant temps also have a direct effect on detonation threshold. 210* is HOT for a turbo car IMO. I like to see under 180 before a run. I do allow my coolant to hit 210 or more cruising to and from the track to boil off the moisture in the oil etc... But at the track the Taurus fan goes on high and 180* or less before I make a boosted pass. If your over 10-15psi at idle your fine IMO. My LS stuff has always been 38-40 once at peak coolant temps after long cruises at idle. More than enough pressure. I wouldn’t worry about yours. I’m not familiar with that pan. I’d assume you could run at least 1qt over the full mark on your dipstick as well. On the LS1 pan car running, jacked, level… I added oil until it started to trickle out of the turbo oil return line. 5.5qts is the capacity listed for the ls1 pan. I was able to add 8qts of oil before it trickled out of the return line. Full 2.5 qts over the suggested amount. So I’d assume you could easily run at least 1qt overfull for a little more capacity. Very common for guys to run 1.5-2qts over full on the ls1 pan anyway. My main concern is the pan pickup being uncovered in “spirited” driving. I had issues with this on my LS1 pan. I’d suggest modifying the pickup (move it to the rear of the sump) or installing Improved Racings baffle setup to help with oil control. Put 2 standard thickness washers behind the oil pump relief spring. (or order a higher pressure spring if you want to do it correctly). 1.) Get some sort of oil control to keep pressures constant. 2.) Get those coolant temps down 3.) Shim or re-spring the oil pump 4.) Run syn oil to deal with the higher temps (higher weight if you want more pressure at temp)
Great advice as always from you. To be clear my cruise temps are 180 or so. When I'm idling at a traffic light my temps are also 180ish. only after beating on it repeatedly do my temps rise to 210ish and fall to 180ish after I get out of it. The LS2/3 corvette pan is suppose to hold 5.5qts as well. Glad to hear you can overfill it a bit. This is something I will definetly be doing once I put my 500ish miles on this "break in" oil. I really like the idea of baffling the pan and will likely do this and the spring when my second oil change comes up.
11-11-2014, 09:58 AM
#36
9 Second Club
I had barely ok oil pressure the first time my cam bearing walked...and the front bearing had almost come right out.
Over time I had noticed a drop in pressure, but as the drop wasnt huge never thought much of it. It was by sheer chance I pulled the motor for something else that I discovered the cam bearing.
So having enough is good, but having strange behaviour is not good.
And as said, during normal driving etc oil temp will literally track water temp. Only when you start pushing hard will oil temps start to rise.
I'd like to think thought that with most decent oils, even up around the 230degF range which still isnt that high, it shouldnt be a concern and any drop related to temperature should be small ?
07-22-2015, 01:49 PM
#37
Well a little update. Here in Houston it has been 100* every day.. I got the car back together and hot idle is down to 20psi.. WOT pulls im seeing 40PSI. My oil temps are excedding 240* coolant temps are high too.. front of the heads are seeing 220 after spirited runs down the free way. I have a lot of work to do and will probably run a remote cooler with a fan in the fender well controlled by the Holley. im goingn to get rid of this 15W30/40 and run some 20W50 and see what happens
Last edited by oscs; 07-22-2015 at 03:48 PM.
07-22-2015, 03:01 PM
#38
9 Second Club
Assuming you have control over water temps...get a colder stat in there.
If you have a colder stat and are still seeing 220degF, then definitely some work needs done.
If you get those temps down, oil temps will also follow.
If you have a colder stat and are still seeing 220degF, then definitely some work needs done.
If you get those temps down, oil temps will also follow.
07-22-2015, 03:51 PM
#39
Yeah, I really need to address the cooling situation. I am Currently not running a thermostat at all.. I have the 33mm plug or whatever it is closing off the port and running it wide open. I dont have a shroud though. I will probably spend sometime re designing my upper radiator mount so i can get a proper Shroud in the car. I'm sure that will make all the difference in the world.
07-22-2015, 04:14 PM
#40
9 Second Club
Yeah, I really need to address the cooling situation. I am Currently not running a thermostat at all.. I have the 33mm plug or whatever it is closing off the port and running it wide open. I dont have a shroud though. I will probably spend sometime re designing my upper radiator mount so i can get a proper Shroud in the car. I'm sure that will make all the difference in the world.
You need to ensure where possible, only cool air can pass through the rad...so sealing off the top/bottom/sides from hot air that might re-circulate can help. Even stuffing foam or something around the sides for a test.
Have you ever tried running a stat ? Does it make a difference over that plug thing ?
Are you still running a mechanical pump or electric ( I'd never trust electric )