c5racr1

Mikec7z

i know where the oil cooler is going to go up in the nose of the car... im looking for the spot to put the valve that takes the oil to the oil cooler, that does not cause an oil pressure drop of any kind in the engine.

The return line to the tank is one such place, and would not need an aux pump.

Tapping into the tank, one would need an aux pump and a thermostat to turn that aux pump on and off, or tie into the stock thermostats somehow.

Replacing the oil cooling brick under the engine with the 2 hose thermostatic valve fitting, to take oil to the front of the car to the cooler, reduces the engine oil pressure i believe, when the oil has to do that circulation path.

Here is what all of this is about. https://www.corvetteforum.com/forums...uto-trans.html

c5racr1

c5racr1

Bill Dearborn

As far as I know the stock cooler with the secondary radiator works well. My oil temperatures don't indicate it isn't working. I had an acquaintance who is a cooling system engineer at Ford look at the oil cooler design and location and he said it should work fine. He didn't believe it would pick up radiant heat from the catalytic converter.

Bill

Mikec7z

if you are speaking about the oil cooling brick attached to the bottom of the lt4... yes, this is what i originally planned to do... but some people and myself noted that simple common sense says that taking the oil on a journey and through a HX or 2, is going to lower its pressure, and it still has a job to do inside the engine.

I dont KNOW that it lowers the pressure, but i am 95% sure it does, and if I can AVOID that pressure drop, and put the oil cooler AFTER the engine and cool the oil down before it goes back to the oil tank, then that is more than fine.

Mikec7z

do you have a photo or a link to a photo of this so i know what you are specifying?

Mikec7z

https://www.corvetteforum.com/forums...180f-212f.html

a few posts down in the thread i linked are the pictures of what I am speaking of, it is an oil line, to a front mounted cooler, and that line is fed by a thermostatic valve, that opens at 180 degrees and closes below that.. and it is all mechanical ran by heat.

Frankly, i am not that interested in cooling the water down, to cool the oil down... this double exchange, is not as efficient as a single exchange, of air cooling to oil in a heat exchanger at the nose of the car... and thats why im going to run an oil cooler in the front of the car, for sure. Possibly 2 of them. Plus, i will greatly increase my oil capacity

Doesn't mean i am not interested in getting a larger radiator, but that will be the end of that most likely. If i can keep the oil cool, ill keep my water cool becuase the water no longer has the duty of keeping the oil cool.

This is probably why Gspeed also made the choice to run an oil cooler at the front of the car.

Pound for pound, cooling the oil down in the HX is the fastest way to cool the entire system down, and bring the temps of everything down.

Instead of tapping into where the oil cooling brick is, like the photos below... i think i will tap into AFTER the engine, where the oil goes back to the tank... to avoid dropping the oil pressure in the engine

So the fitting shown below, is what i was originally going to do, but i changed my mind and will do a similar fitting attached to the oil line that returns to the oil tank, for the reasons i listed in posts above this one. Then I will not be dropping the engine oil pressure, but i will be cooling the oil directly, anytime it is above 180 degrees.

WhiteSands

Bill Dearborn

He just looked at a car that was available to him at the time. You do know that GM went to this type of cooler in 2009 with the advent of the C6 ZR1 and then incorporated it into the C6 Z06s later on as it resolved problems they had with the original C6Z oil to air oil cooler cooling the oil too much and not letting it warm sufficiently for highway operation in colder climates.

Bill

Mikec7z

right, but that is where the cool thermostatic valve gismo comes into play.

It ALWAYS flows 10% to keep the oil from solidifying in the coolers, even when it is "closed"...

but it ONLY flows 100% of the oil through the cooler when the valve itself sees the oil is above 180 degrees. (they have other higher temperatures too in the 200's for it to open and close, you pick which one you want)

So yes, it can be cold out, the oil, mostly, wont touch the cooler, and the oil that does, will be put into a large holding tank where it can equalize in temp with all the other oil.

The other thing you can do is have a cover to go over the cooler in the winter time if you live somewhere very cold. You can also simply unplug the lines from it, and just put a U turn on the thermostat fitting or remove it all together for the winter. The oil cooler can stay there, just tape off the ends or the hose ends that lead to it.

Mikec7z

long story short... YES, GM was too cheap to pay for the patent pending thermostatic gizmo It was black or white with them... "all the oil flows through the cooler, all the time, and if that doesn't work, abandon ship."

.... they are idiots. Genuinely.

Warp Factor

Mike, I don't think it has anything to do with idiocy.
And I doubt that GM's decision to take another route has anything to do with any sort of patent protection on the oil thermostat device you have shown. Oil cooler thermostats have been around for easily 40 years (probably longer). There are other reasons to use liquid-to-liquid heat transfer between the oil and the main engine coolant:

Faster oil warmup. On a 9-10 quart oil system, oil warmup can be very very slow, without being tied in to the main coolant. In a cold climate or short trips, the oil may never warm up enough to purge moisture effectively. GM's choice allows heat transfer in both directions, whichever is needed.
Needs only one thermostat rather than two (fewer parts to fail, and thermostats are a common failure item).
Fewer oil lines to leak or fail.
The ability to easily get more of the old oil out during an oil change, than if there are remote heat exchangers and lines.
Faster oil pressure rise on startup after an oil change, than if some or all of the oil had been drained from these external lines and coolers.
Keeps things slightly simpler for dealer techs, some of whom are inadequately trained or experienced to work on these already very complicated cars. I have service done at a nearby super-high-volume Corvette dealer, so I don't worry much about that, but not everyone is in that position.

Mikec7z

Thanks for the explanation Warp, always a valuable person to this forum with your insight.

i spent yesterday calling around to a few places who are experts in this field, and not just in the automotive industry but other industries as well, and a couple of my friends called around as well.

3 of us who have these cars have come to a consensus, we will not add an oil cooler to an engine that adds any pressure drop whatsoever.

So that eliminates the cooling brick location for tie in.

After the scavenger pump, on the way back to the tank, is going to the location we tie into. Is it THE most efficient spot to cool the oil? No.

But will it provide cooling? Yes. Keep in mind, air compresses, so as the PD scavenger pump is moving the oil through the cooler and back to the tank, the air bubble/pockets will become much smaller in volume than normal, and thus it wont be THAT un-efficient.

That being said, our logic is simple, ANY cooling to the oil is good, so long as it does not drop engine oil pressure, and the oil cooler tied in on the return line, will provide some cooling.

And ALL oil that flows through the motor, has to flow back out through the scavenger pump, so all the oil will have to pass through the cooler IF the car oil is above the specified 180/etc temp

You are correct it WILL be more difficult to change the oil, as i mentioned this prior over in my other thread, but it will keep these cars from overheating, and that is a tradeoff we are willing to endure.

I personally think GM is foolish for not exploring this option, as it would almost assure ALL z06 vettes HAVE TO BE brought into dealerships fro oil changes, instead of walmart of jiffy lube.

It is actually costing them money NOT to do it this way, and they COULD keep their cars from overheating, and also keep the car running stable in cold weather via use of the thermostatic valve attached at the scavenger line.

We will be testing this by next month hopefully.

Bill Dearborn

I believe they never send 100% of the oil to the cooler or block 100% of the oil going to the cooler. The thermostats I am familiar with swing between 15% flow and 85% flow in order to prevent air bubbles in one of the paths. If you totally block one path or the other you have a higher likelihood of getting an air bubble in the blocked path when that path is opened can flow into the engine possibly damaging the bearings.

When I had my C5s I had a DRM Ron Davis Racing Radiator with built in engine oil cooler in the passenger side radiator tank. This was the cool side of the radiator and it was difficult to get the engine oil warm when driving in mid 40 degree temps at 70 mph in 6th gear. It actually took over 20 miles before the oil temp reached 150 degrees. I could get the temps up faster by driving the same speed in 3rd gear but as soon as I went back to a reasonable gear for the speed the temp tended to settle back toward 150. With this setup and a stock 186 degree thermostat on a 90 degree day I could run 40 minute track sessions all day with coolant temp right at 200 degrees and oil temp right at 230 degrees.

With my C6Z I had similar issues although not as bad. In 40 degree Its oil to air cooler would also slow the rise in oil temperature to the point it took at least 10 miles of driving at speed to get the oil temp over 150. The C6Z would run all day long on 90 degree days with coolant temps of 230 degrees and oil temps of 260 degrees.

I resolved the problem on my C5Z by updating the DRM plumbing to the Ron Davis Radiator with a thermostatic bypass valve. This valve had a temperature setting of 185 degrees. It always maintained a 15% minimum oil flow through either of the lines. However, what was interesting were the track results, after the valve was installed both of those temps jumped 30 degrees. 230 degree coolant and 260 degree oil. Limiting the flow through the oil cooler to 85% of the flow was enough to raise the overall temperature of the engine by 30 degrees. To give you an idea of what it was like without the RD Radiator before I installed it I ran an event with 40 minute sessions on a very hot day. As i saw the checker flag for the event I looked at the oil temp display, it was 319 degrees.

I really don't see any issue with the C7 oil cooler. If you cool the coolant sufficiently you will cool the oil sufficiently.

Bill

Mikec7z

That is correct. The good news here is, any and all air bubbles already exist in the scavenger line, and they are going to be swirled out and/or rise to the top, at the tank in the fender, as that is the tanks pre-existing/designed purpose to remove the air from the oil.

What you may be implying is that I CAN run a valve that does a 100% open and close, from one path the to the next since the aerated oil is not an issue since it is returning to the tank, and then i get a 50 degree drop instead of 20 or 30, and that is not a bad idea Bill

As far as not 100% cooling and only 85%-50% cooling, from the 85% open valve... this 85% valve is the same fitting used by the other gentleman in the other thread racing up the cali mountain said he saved 20 to 30 degrees with just his little oil cooler... and it is plumbed where it also messes with the engine pressure via the lt4 cooling brick location under the engine.

Ill be using a larger cooler and wont be sacrificing engine oil pressure (and possibly a different valve now that you got me really thinking about it)

So any and all cooling is welcome, and i believe i will get over 30 degree drop of both the engine oil, engine coolant, and also trans coolant... without touching the cheeks of the car... yet. And will also NOT be adding more air resistance to the vertical radiator and blower heat exchangers etc.

Bill Dearborn

The downside is you are changing the engine's lubrication system. Anything that happens to the bearings is on you not GM since it can be said the cooler impacted the lubrication in some way or the other. If you improve cooling of the coolant you can get the same result without all of the risk. Sure there are things that can go wrong that way as well but you have more time to react to them. it does take time before you go from over heating to frozen engine. if you suddenly lose coolant due to a bad aftermarket component or installation you won't lose the engine because you have time to react.

Bill

Bill

Mikec7z

i agree with that. That is one of the main motivators that has me plugging in AFTER the engine has used that cycle of oil... that way if the system springs a leak, i MIGHT smell the oil, or if it starts to leak slowly, i can catch the leak between drives. Believe me when I say, if and when i do this on the next vehicle I get here in a couple months, I WILL be checking the oil level often and looking for leaks around the new hoses etc.

I will conduct a lot of odd little tests to assure it is all working as I assume it will, before i go crazy with it. I will probably also install my own secondary oil pressure sensors and some sort of alarms. I know there is obd port plugin that reads and has software as well and can alarm of certain problems.

Drew27 is working on some killer software as well.

Remember Jurassic park when they said the raptors test the fence for weakness constantly, and they learn... im related to one of those things

There's a reason i figured out the p0106 and its stair step limits as it is approached, while it confused everyone else for a few years.

Mikec7z

do the cars have a "low oil" light Bill? I don't think they do since the system is so complex. But i figured if there was a way to detect low oil, or lack thereof, while driving the vehicle, you would be the one to know.

Z06Norway

Have you considered to have an oil/water cooler prior to sending it to oil/air cooler in this Stage 0 no cut option ?

I am one of the guys that loves my Vette, but hate to admit that it does not cool enough for hard track duty :-(

My Callaway GT3 car has an water/oil cooler and it works great..

Seems you have now alot better water temp than stock, so it might be able to draw 20-30 degree out of oil prior to sending it to air/oil cooler ?

I was set on selling my second C7 Z06 due to this frustrating overheat, but i am now on the fence and will likely be a customer this fall

great work btw, read your first post also :-)

regards
Rune