oil cooler, your thoughts Options

[Downunderman]

Added a factory thermostat while I was at it. The lines run through the sills on the left hand side.

[Downunderman]

This is the new clutch. Modified in Brisbane by Jim Berry at RaceClutch. 2400 lbs of clamp with 5 button carbon metallic facings and solid centre.

[Downunderman]

Another phot of the box up front.

[Downunderman]

This is a bit OT but you don't see these very often. Repco Brabham V8 fitted to an Elfin sports car; kind of like a baby can am car. 3.5 litres and 380 hp. This was at the historics at Eastern Creek last week end.

[SpecialK]

Copper oil lines in the rockers.
I thought somebody would say something about that.

I will...If thin copper strips were soldered on as heat sinks/cooling fins. Even better.

How would you like to have a ten foot long oil cooler? (IMG:style_emoticons/default/idea.gif)

KT

Okay, I wasn't going to say anything about my plans for routing my oil coolers for fear of getting slammed by all of the fart smeller's....I mean....anyway, the guy's that now there "shizzle" when it comes to effective set ups on these cars, but here it goes. Please be warned I can tell you about it, but then I'll have to kill you (IMG:style_emoticons/default/ar15.gif) (IMG:style_emoticons/default/biggrin.gif)


It all started with my air conditioner condenser coil location...hate the stock location and set up for numerous reasons, and hey, that's where I was planning on originally sticking my RX7 oil cooler anyway. So I decided to fab my own condenser coils out of three concentric spirals of soft copper (I do a lot of HVAC stuff), 4' long each, with varying tubing dia. to prevent/reduce any restrictions. There'll be one coil each mounted in CAT ducting in both rear fender wells, with an inlet in each rocker panel (was to be X1/9 side scoops, but that's still up in the air), and exhausting behind each rear wheel kind of 996 like.

"But what if you're not moving Kevin", already thought of that. I've got two 240 cfm 4" marine (read: cheap, water resistant) bilge blowers that'll mount in the inlet of the 4" CAT duct upstream of each coil, controlled by a sail-switch (HVAC item) mounted in the front bumper. I can adjust the spring tension of the sail-switch to "deactivate" the bilge blowers when I get to about 25 mph or so (they'd only run if I'm sitting in traffic, or barely moving...gotta keep Daddy cool in the summer out here). This got me to thinking of possibly doing the same thing in a smaller 3" diameter (still 3 concentric spiral tube) mounted in the front fenders for oil cooling (IMG:style_emoticons/default/idea.gif) .....

My '73 (IMG:style_emoticons/default/wub.gif) has the 916 front and rear bumpers which I really like the look of, but didn't particularly like the idea of cutting a big hole in my front trunk to accommodate an oil cooler (especially since it's the only car I have that has a solid front trunk). The "driving light" recesses in the bumper were not in a particularly good location for me to duct to my front fenders, so I'm going with cutting (neatly) the top and bottom out of the little wing thingys on each side leaving the leading edge of the wing/spoiler, and using a spare engine lid mesh for protection. I'll fab a FG insert to fit on the back side of the spoiler to duct the air to the outside where the 3" CAT duct and oil cooler(s) are located. The exhaust location I'm still (IMG:style_emoticons/default/headbang.gif) over. I was originally going to bring the duct over the front wheel and down to louvers in the rocker panel, but that would trap the heat if I wasn't moving (no blowers up front with this plan....yet). The "plan 'B'" was to exit higher on the fender, kind of Z3ish, which would allow the heat to "draft" through the duct, just like a flue on a furnace, if I'm standing still (I know, not much...but better than nothing...3" bilge blowers? (IMG:style_emoticons/default/idea.gif) ). There are a hundred little details I'm omitting (like the oil cooler drain hidden behind the front license plate) to keep from boring you do death...if it's not too late already (IMG:style_emoticons/default/unsure.gif) , but in a nut shell, that's it.

Blast away! (IMG:style_emoticons/default/fighting19.gif)

[ArtechnikA]

other question was, can you cool the oil too much?

few issues going on here ...

oil can be too cool, which is why you must have a good (factory or Troutman, same Behr element in a different container) thermostat if you have a cooler. so - supposedly - the oil will not be sent on its merry way through the plumbing if it's not already warm enough. aftermarket oil thermostats seem to be set right around 180F, which i think is too cold for this purpose; the factory T-stats seem to be set higher. i saw a couple of different numbers this week and i'm still trying to sort 'em out.

so the theory is that if the oil's cold, it won't be cooled. so you just barely hit 181, a big slug of oil is released to the cooler, where it (and all the already cold oil in the cooler and oil lines) has heat removed. it's no longer going to be 180F when it returns from that trip. so the thermostat closes again... clearly, if the oil's REALLY hot you're fine.

the first factory coolers (911) used tinned steel oil lines and a trombone at the front that basically just turned the flow around -- most of the cooling was in fact performed by the lines which-- on a 911 - are in the airstream all the time. put the lines in the rockers and now you have no free airstream cooling. Elephant has finned lines that the HiPo 911 guys like -- but if you put a finned line in a box it hasn't bought you anything. Scoops? get serious... they pick up debris, grit, and water, and add drag you don't need. anyway - a good exit for the airflow is probably as important as getting the air in...

copper (and aluminum, so don't go there...) will work-harden from the vibration and crack eventually. if you mount it in nice rubber Adell clampswill that occur in your lifetime? who knows... but the factory used steel and/or brass when they did metal lines...

so - in theory, yes, you can overcool the oil, but one of the reasons we like good oil is that it'll lubricate well even at suboptimal temperatures (although it won't be as efficient...) in practice, what it means is that you can spend too much time, money, effort, and weight making oil cool, and that's not efficient.

MHO is that plumbing should be reliable, and coolers should cool. looking for additional cooling capacity in the lines when you already may or may not need a cooler seems effort mis-spent. (Porsche did it because they were trying to avoid the cost of actual radiator oil coolers...) lines run through the rockers will be reliable, but i wouldn't count on them to be a significant part of your heat rejection package.

i don't think i'd have much heartburn with straight runs of rigid wall copper in grommets and Adell clamps run through the rockers. (yes, this means i am mellowing on this issue...) but you also have the issues of attaching flex lines to the rigid pipes, and there are issues there. solvable issues, but stuff you've gotta deal with.

[maf914]

Are typical oil thermostats modulating or on-off. In other words, when the oil reaches the set point does the thermostat open slightly and continue to open as temperature rises or does it open completely? I assume they are on-off.

This makes me wonder how often they cycle. I know this would be based on the combination of cooler and line sizes, but I can't quite visualize how this all works together. It seems that an oversized cooling system will cycle excessively and an undersized system will remain open continuously. How do you size the system properly? Lots of variables. (IMG:style_emoticons/default/confused24.gif)

[maf914]

This  is a bit OT but you don't see these very often.  Repco Brabham V8 fitted to an Elfin sports car; kind of like a baby can am car.  3.5 litres and 380 hp.  This was at the historics at Eastern Creek last week end.

Howard,

Is that the same engine that Jack Brabham and Denny Hulme used in the middle 60's to win the championship? Wasn't it a DOHC V8 built on the Oldsmobile aluminum block? If I recall correctly it was the first year for 3-liter F1 engines and Repco-Brabham built this because there were no established customer engines available yet.

BTW, your oil cooler installation is very neat. Any problems bleeding air from the system with that horizontal coil placement?

[ArtechnikA]

How do you size the system properly?

you spend some time looking at the heat rejection rates published for the coolers you intend to use, and how guess how much more you'll need than you've got. you discount the cooling effects of the lines - anything you get there is bonus.

then, you discover the benefit of testing.

if the car hits the red before the end of the session, you do not have enough. if you don't have a bigger cooler on the truck, you either decide to risk the engine and race anyway or you decide to pack up and go home. if the engine won't reach operating temperature within a few laps, you have too much. this is usually easier to correct at the track with a few strips of tape.

this is but one reason racer's tape comes in so many colors ...

[Trekkor]

Now we are having that open discussion!
Remember...A bunch of guys in the garage, throwing ideas off each other. (IMG:style_emoticons/default/idea.gif)

Thanks for the input!

With the copper, I'm not worried at all about cracking.
You'de have fold it back and forth over your knee to break it.

Why I know this? I have folded it over my knee and I have two copper coolers on my boat.
One is 1 1/2" pipe with a 1/2 " pipe inside. The oil flows through the 1/2" pipe while fresh water jackets the oil line as it flows to the raw water pump on the engine.
This set up is available in all the marine catalogs.
I made my own custom to fit my boat for $50 in copper schtuff. The pre-made ones are like $100 and about 16" long, mines six feet long. (IMG:style_emoticons/default/mueba.gif)

Engine cooling? Yes, copper fresh water heat exchanger.
A large copper tank with a pipe splitting it internally down the middle. As hot coolant passes next to the cold sea water heat is exchanged through the copper wall.
Thus, my Corvette boat motor stays below 175 all day long. And no crud or squid or sea weed in my motor.

Copper is an excellant metal for heat transfer, one of the best, no one will dispute that.

KT

[J P Stein]

Are typical oil thermostats modulating or on-off.  In other words, when the oil reaches the set point does the thermostat open slightly and continue to open as temperature rises or does it open completely?  I assume they are on-off.

This makes me wonder how often they cycle.  I know this would be based on the combination of cooler and line sizes, but I can't quite visualize how this all works together.  It seems that an oversized cooling system will cycle excessively and an undersized system will remain open continuously.  How do you size the system properly?  Lots of variables.   (IMG:style_emoticons/default/confused24.gif)

The 9eleben engine thermostat ....which is also used in the Troutman unit... opens gradually starting at around 185 deg and fully opens at about 212. I've tested these in a pan of water on the stove.....the wife loved that (IMG:style_emoticons/default/biggrin.gif)
They cycle continuously in response to heat input.

These thermos also have a pressure bypass .....excessive back pressure is bled around the cooler to protect it.....that save my motor when I screwed the pooch plumbing the system....blew the cooler tho. Fluidyne replaced the ex cooler FOC......which gets them kudos from me. Good parts are a blessing to dumbshits like me (IMG:style_emoticons/default/biggrin.gif)

[StratPlayer]

I have a front mouted oil cooler, hot air venter through fender well. I put a Mocal thermostat in mounted close to the engine. 180 degree thermostat. My cooler works just fine I don't think I would go without one now that I've had this installed. Going up steep mountains on a hot summer day and my temp stays put... I've had a front mounted cooler now for almost 4 years without any problems or leaks.

[Series9]

Here's a couple of pictures of my setup.

[Series9]

more...

[Downunderman]

Mike, very loosely based. The blocks were a different casting and the heads were sohc, but yes same type of engine. This one grew a bit. They also came in 2.5l for the Tasman Series if you can remember back that far.

haven't tried the cooler yet. Waiting on a guide tube for the gearbox which wont get here until Friday week after next. I expect that whatever is scavenged from the case will find its way through the cooler when the thermostat opens. It doesn't have any choice.

[Downunderman]

JP, my wife was not particularly happy with me washing IDA's in the dishwasher (without anything else in there) but she really went off a bit when I preheated a bunch of (clean) cylinder heads in oven of her new stove. So much easier to weld when they are hot.

[J P Stein]

JP, my wife was not particularly happy with me washing IDA's in the dishwasher (without anything else in there) but she really went off a bit when I preheated a bunch of (clean) cylinder heads in oven of her new stove. So much easier to weld when they are hot.

(IMG:style_emoticons/default/laugh.gif)


Whenever I carry car parts near the kitchen the wife says "Now wait a damn minute. Whadaya gonna do with that".

Gotta add a dishwasher & stove to the shop......or a cot & pillows (IMG:style_emoticons/default/biggrin.gif)

BTW, Nice set-up for the cooler.

[SpecialK]

JP,  my wife was not particularly happy with me washing IDA's in the dishwasher (without anything else in there) but she really went off a bit when I preheated a bunch of (clean) cylinder heads in oven of her new stove.  So much easier to weld when they are hot.

(IMG:style_emoticons/default/laugh.gif)


Whenever I carry car parts near the kitchen the wife says "Now wait a damn minute. Whadaya gonna do with that".

Gotta add a dishwasher & stove to the shop......or a cot & pillows (IMG:style_emoticons/default/biggrin.gif)

BTW, Nice set-up for the cooler.

Got busted myself curing the cylinder coating in the oven (IMG:style_emoticons/default/unsure.gif), luckily she didn't catch them in her new dishwasher (IMG:style_emoticons/default/spank.gif) . She was supposed to be shopping with her sister all day but came home early (couldn't find a single piece of clothing in an entire mall that she liked (IMG:style_emoticons/default/huh.gif) )....definitely need my own dishwasher and oven installed in the garage to match the "beer only" refrigerator! (IMG:style_emoticons/default/beer.gif)

[SpecialK]

With the copper, I'm not worried at all about cracking.
You'de have fold it back and forth over your knee to break it.

Totally agree! If properly isolated there is no danger of work hardening. It's also very easy to bend into shape for routing, can handle any pressure a car can throw at it, and best of all it's cheap!

FYI: Soft copper used in HVAC applications uses different fittings than the kind you'd get at a hardware store. Soft copper sizes are measured by O.D., rigid copper (for household plumbing) is measured by I.D.. Another advantage of using refrigeration copper fittings is that you can get them in larger radius "sweep" elbows which will help reduce restrictions. It can be easily flared for use with fittings....and did I mention it's cheap!!


Kevin

[Trekkor]

Flared soft copper...nice.

I had thought to just sweat on threaded fittings for the braided lines to attach to.

Here's something new. Louvered rockers to get air in there for cooling the lines. (IMG:style_emoticons/default/idea.gif)

KT