Oil to coolant heat exchanger

[EcoCivic]

Actually I am questioning how effective the OEM style cooler is in the first place. This picture I found of an OEM cooler from an Integra shows that the oil coming out of the engine goes straight through the cooler without being forced through the heat exchanger. Look at the rectangle hole (where the oil enters the cooler), you can see right through it. And the oil coming out of the filter goes straight back to the engine. What am I missing here? https://i.ebayimg.com/images/g/y78AA...j2/s-l1600.jpg

[me and my metro]

Those are designed to slightly cool hot oil down to coolant temp. They are set up the same way on the Ford gas engines I work on. The GM coolers that use 1/2” tubing to connect to the radiator are only partial flow so even if they plug up the engine will still live. I know you are looking to warm the oil quicker for fuel economy. Thinner oil may give better results in my opinion. The problems I have seen here is cold oil in fire fighting equipment and engine failure. We have installed oil sump heaters in some of the gas engine trucks with good success. I had one on a VW bus back in the early 80s to aid cold starts and faster warmups on an air cooled engine.

[EcoCivic]

Originally Posted by me and my metro

Those are designed to slightly cool hot oil down to coolant temp. They are set up the same way on the Ford gas engines I work on. The GM coolers that use 1/2” tubing to connect to the radiator are only partial flow so even if they plug up the engine will still live. I know you are looking to warm the oil quicker for fuel economy. Thinner oil may give better results in my opinion. The problems I have seen here is cold oil in fire fighting equipment and engine failure. We have installed oil sump heaters in some of the gas engine trucks with good success. I had one on a VW bus back in the early 80s to aid cold starts and faster warmups on an air cooled engine.

Ok thanks, so I guess I am not totally missing something obvious. I don’t think that cooler will do what I need then (keep oil and coolant temps within 10 or so degrees the majority of the time) if a significant amount of the oil is going to be bypassing it.

To be clear, I am not expecting a measurable MPG or power gain from installing a heat exchanger, but I’m sure it won’t hurt. I am into getting the best fuel efficiency, but I am more of a high performance guy. The reason I want a heat exchanger is longer engine life and so I can safely run the engine hard sooner. In my opinion, it’s ridiculous to not be able to safely floor it getting onto the highway several miles from my house even though the coolant is up to temp because the oil is barely starting to heat up by then.

What oil temp would you say it’s okay to run the engine hard at? I used to think I should wait for the oil to get to around 170 degrees minimum before I floor it before I installed the gauge, but now that I installed the gauge I see that the oil sometimes won’t reach 170 in cool weather, I am starting to rethink that one. Thanks

[Daox]

If you have oil pressure you're pretty much fine to floor it. So, a few seconds at most after starting the engine? Having thinner oil actually protects things a bit worse. Thinner oil mainly is used to increase efficiency.

[me and my metro]

Almost all crank bearing failures are caused by dirty oil and running out of oil. I used to race a car in my youth and never had a bearing failure. We inspected and replaced bearings during the season. We did loose an engine one time from a crankshaft breaking but all the bearings were still good. The main web had cracked in the block and we did not catch it in time.

[EcoCivic]

Originally Posted by Daox

If you have oil pressure you're pretty much fine to floor it. So, a few seconds at most after starting the engine? Having thinner oil actually protects things a bit worse. Thinner oil mainly is used to increase efficiency.

So there is no harm in running a cold engine hard? I have heard that pushing it hard with cold oil is terrible for the life of the engine because it may be too thick to flow adequately and because the clearances are incorrect at below operating temps. Here is one article about why it’s bad. I don’t know how true it is, but there must be some truth to it since Honda engines won’t activate VTEC until the coolant is warmed up and some engines have a variable redline that goes up as the engine heats up.

Keep Your Engine Alive: The Importance of Oil Temperature | Tuner University

[Piotrsko]

That was true of cars running 10-30 or 20-50. Most anything today has tighter tolerance and thinner oils so after a couple of minutes running, you have everything lubed. Ever see 5-30 on a cold morning? And my F250 takes 20 miles to warm and we're at 160k miles.

[EcoCivic]

Originally Posted by Piotrsko

That was true of cars running 10-30 or 20-50. Most anything today has tighter tolerance and thinner oils so after a couple of minutes running, you have everything lubed. Ever see 5-30 on a cold morning? And my F250 takes 20 miles to warm and we're at 160k miles.

Thanks. So would you say it’s okay to floor it once the oil reaches 100 degrees? Why won’t VTEC activate until the engine is warm if it’s not harmful to the engine? This car calls for 5w20 oil

[MeteorGray]

My Mazda specs 0w20. I wonder how thin they're going to get? Is there any -20w-00 out there? Maybe when the new Ice Age hits.

[Piotrsko]

Originally Posted by EcoCivic

Thanks. So would you say it’s okay to floor it once the oil reaches 100 degrees? Why won’t VTEC activate until the engine is warm if it’s not harmful to the engine? This car calls for 5w20 oil

Heavy acceleration yes, floor it not so much because you will still have temp differences that can cause failure. Bearing surfaces are ok however.

Actually thinking about it, this strikes me as they same scenerio of an Alaskan aircraft engine and AFAIK, they make TBO.

Unknown. Could be a emissions strategy.