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go-fish
06-10-2007, 11:09 AM
A few questions on oil cooling. First of all, who makes a good cooler and how much does it add to the cooling effect?
Does it get run similar to a remote filter system? Does a filter go inline before or after the cooler?
Finally, does having a remote dual filter system help even just a little?
I am considering doing a 1/4 block fill to strengthen the bottom end and would like to make up for the lost water jacket volume to allow for an alternative method of cooling.

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06-10-2007, 12:01 PM
Setrab and Mocal are a couple of the companies that make good coolers. I believe B&M also have some that are good for engine oil.

IMO you should always run the cooler after the filter. Cool oil is thicker/more viscous than hot oil, so cooler oil will cause more restriction in the filter.

If you've got a remote filter system then adding a cooler is going to be really easy. Instead of plumbing from the filter back to the engine you will go to the cooler, and then to the engine.

I like the plate-type coolers, not the tube-and-fin type.

On my car I am installing a thermostat for two reasons:
First, I'm up north, so sometimes the cooler could be too efficient and overcool the oil.
Second, the theromostat I'm using reduces restriction when the oil is cold. (Most likely all oil thermostats do, but I don't know.) The way mine ( http://www.thinkauto.com/ ) is designed, the path to and from the cooler is always open, but when the oil is cold there is a second path open that allows the oil to return without going to the cooler. In effect it short circuits the path, but both paths are open.

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06-10-2007, 12:02 PM
BTW, if you don't have the dual remote setup yet let me know.

go-fish
06-10-2007, 03:02 PM
I found a kit from Derale that is a sandwich type. Goes in between the block and filter, in my case 90* filter adapter.
It has a thermostat and flows to the Setrab stacked plate style cooler at 180* F.
http://store.summitracing.com/partdetail.asp?autofilter=1&part=DER%2D15602&N=700+0&autoview=sku

Lowend
06-10-2007, 03:52 PM
I've used that kit before... not bad.
Earls also makes some very nice setups.
Run a thermostat for sure; on most V8's the last thing you want to do is cool the oil during the first 5 minutes of run time

go-fish
06-10-2007, 05:23 PM
Is there any preference on how far you can run the lines? Pressure loss?
Also, would it hurt if I put a couple of 90's in there to get it routed real cleanly to the front?

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06-10-2007, 05:54 PM
Any sharp turns add restriction. Larger radius fittings are much better than tight 90s.
Hose also adds restriction-there is a certain amount per foot, depending on the size. -10 is the minumum you should run, IMHO. -8 could be done, but probably shouldn't. -12 may be overkill.

chicane67
06-10-2007, 06:47 PM
Firstoff, keep in mind what is considered hot, too hot, cold, and too cold.

For most, you'll never really see the upper end of hot for most conventional engine oils... and even more so for a full synthetic. But for an approximate, I would definately keep the oil below 250*F. Now as for cooling, you might be surprised by what is actually considered being too cool. I wouldnt run the engine oil below 210-215*F. FWIW, you will see the best volumetric efficiency and performance with the oil 40*F higher than the engine coolant. So, if you are running a water temperature of 180*... the engine oil should be 220*.

A few other pointers:

ONE... do not run a remote "dual" oil filter... as it has twice the pressure loss as a single. If you need more/better filtration... use a better filter.

TWO... line size will have a lot to do with overall length of a singluar line. I would however, recommend using 1/2" line (as a minimum... and you dont rally need much more than that unless its really, really long) thru-out.

THREE... a 90* fitting is about the worst thing to use. So yes... a 90* can and most likely will increase pressure loss.

FOUR... Filter the oil before cooling. If you ever have problems, like something coming apart internally, it will keep the junk out of the cooler.

I am a fan of the Setrab coolers if you choose to go with an air to oil cooling system. But... the cooler that is shown in the about Summit Racing link... is WAY too small to do any good. A 12 5/8 x 13" would be about the smallest cooler to consider.

But really... you need to install a mechanical temperature guage to see if you are really having an issue... and how much of an issue you need to address before any parts purchase. Meaning, that if you only need to cool a little... there is really no reason to spend big, when its not necessary.

Hidro
06-11-2007, 02:57 PM
Firstoff, keep in mind what is considered hot, too hot, cold, and too cold.

For most, you'll never really see the upper end of hot for most conventional engine oils... and even more so for a full synthetic. But for an approximate, I would definately keep the oil below 250*F. Now as for cooling, you might be suprosed by what is actually considered being too cool. I wouldnt run the engine oil below 210-215*F. FWIW, you will see the best volumetric efficiency and performance with the oil 40*F higher than the engine coolant. So, if you are running a water temperature of 180*... the engine oil should be 220*.

A few other pointers:

ONE... do not run a remote "dual" oil filter... as it has twice the pressure loss as a single. If you need more/better filtration... use a better filter.

TWO, line size will have a lot to do with overall length of a singluar line. I would however, recommend using 1/2" line (as a minimum... and you dont rally need much more than that unless its really, really long) thru-out.

THREE... a 90* fitting is about the worst thing to use. So yes... a 90* can and most likely will increase pressure loss.

FOUR... Filter the oil before cooling. If you ever have problems, like something coming apart internally, it will keep the junk out of the cooler.

I am a fan of the Setrab coolers if you choose to go with an air to oil cooling system. But... the cooler that is shown in the about Summit Racing link... is WAY too small to do any good. A 12 5/8 x 13" would be about the smallest cooler to consider.

But really... you need to install a mechanical temperature guage to see if you are really having an issue... and how much of an issue you need to address before any parts purchase. Meaning, that if you only need to cool a little... there is really no reason to spend big, when its not necessary.


Good info. Thanks!

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06-11-2007, 05:50 PM
Chicane, I question your statement that a dual filter assembly doubles the restriction. I believe it should reduce the restriction, since it allows the oil two paths to flow through.
They do not flow from one filter into the other.

go-fish
06-11-2007, 07:40 PM
Thanks for the replies.

chicane67
06-11-2007, 07:47 PM
Chicane, I question your statement that a dual filter assembly doubles the restriction. I believe it should reduce the restriction, since it allows the oil two paths to flow through.
They do not flow from one filter into the other.

Twice the material... twice the resistance to gross flow... no matter if its a single route or not, per filter.

The "goes into" still equals the "comes out of".

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06-12-2007, 08:39 AM
Twice the material... twice the resistance to gross flow... no matter if its a single route or not, per filter.

The "goes into" still equals the "comes out of".
But you are sending half the oil to each filter. Really you have twice the "holes" in the filter for the oil to flow through.

Fluids follow most of the same laws as electronics. If you install two resistors in parallel you get half the resistance.

Look at it this way: If you completely plugged one of the filters you would have the equivalent of a single filter assembly. Adding a second filter allows more flow and therefor lower resistance.

68sixspeed
06-12-2007, 08:52 AM
Another side note that Chicane lead into, make sure you need the cooler first- it takes horsepower to run any kind of remote filter and/or cooler. On open wheel modifieds they unhook the coolers once the temps drop to gain 8-12hp on a 400hp motor. That shows a bit of how much that pump is working, and in the case of a SBC or BBC, how much more strain is on the distributor gear, timing chain set, etc. -Dan

chicane67
06-12-2007, 10:09 AM
But you are sending half the oil to each filter. Really you have twice the "holes" in the filter for the oil to flow through.

Fluids follow most of the same laws as electronics. If you install two resistors in parallel you get half the resistance.

Look at it this way: If you completely plugged one of the filters you would have the equivalent of a single filter assembly. Adding a second filter allows more flow and therefor lower resistance.

An increase in the amount of fluid circuits to which the fluid can flow, does not negate the presence of resistance. Nor will this specific increase in available circuits make that resistance any less. By adding the second filter it would allow more gross flow, but each vessel (fluid circuit) will have the same resistance as the next if it were identicle (length/diameter/fittings etc etc). The only reason you would have more flow, would be from an increase in volume related to the increased number of fluid circuits... but it does not change the resistance.

Just because you provide two fluid circuits does not mean that its going to be any less restrictive. The more you disrupt fluid in linear flow, the more inhearent that resistance becomes at a given temperature. Meaning, that with an increased number of circuits and angle changes in flow direction (anything over 12* will induce resistance from reversion), that disruption itself becomes an increase in resistance. There is no way it will be less than a singular circuit... and by the typical, computational fluid dynamic models (CMD) it will show this as an increase.

Trons and fluid medium both 'flow'... but not in the same mannerism.

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06-12-2007, 04:52 PM
I agree with you that the more and sharper turns there are the more resistance there will be. Poorly directed flow will cause even more resistence. However, I think that since we are talking about .500" to .750" tubing and ports that this resistance will be minor. I believe it will be a small fraction of a percent. Yes, it is there, but I don't believe it will be significant.

A small filter will cause more resistance than a large filter, due to the lesser surface area. The more surface area there is, the less resistance there will be, because there is less fluid being forced through the same area in the same period of time.

Maybe we are not quite understanding each other.
You say that there will be more flow due to the increased pathways, but the resistance will stay the same.
I say that since the flow is staying the same, the increased pathways will result in reduced resistance.
If we had a filter assembly that caused a 10 psi drop in oil pressure at 100 gpm and we added a second filter assembly, in parallel, I say that at 100 gpm of total flow we'd have a 5 psi drop, or perhaps 6, taking the additional turbulence into account. This is because we are running 50 gpm though each filter, not the full 100 gpm.