Think about flow inlet area... you have one big cooler choked off by a small bumper opening (not to mention that 34 will nearly be dragging on the ground if you have popup headlights, just waiting to dump all your oil when you hit something low). And remember, once you rip out the stock cooler, you need to put in a thermostat

Best bet (i think) is twin 19 rows.... even though the coolers are smaller they are really efficient as they take advantage of the twin bumper openings. Also I really encourage people to get QUALITY oil coolers... mocal/setrab/etc as the efficiency of these higher end units is typically better than the cheaper ones.

 

I usually see 220-230f for oil out on the track. Occasionally I see 245f but thats quickly solved by short shifting for half a lap.

 

Fans move a fixed volume of air. Assuming that the cooler has ideal inlet and outlet ducting vehicle speed decides how much air flows through the core. I think the question is at what speed will the vehicle naturally move more air through the cooler than the fan, and if your average speed is higher or lower than this decides if the fan is an obstruction.

 

Airflow through the oil cooler fins is not simply a function of vehicle speed, the cooler is a restriction and will need air forced through it. This is why you need air ducts, to increase the pressure and force air through the cooler.

I don't disagree that the fan motor can inhibit airflow through some of the oil cooler fins, but in many cases a fan will be able to force more air through the cooler than relying on ducting and vehicle speed. I haven't tested this (on an FD oil cooler) so I can't guarantee a fan will work better than ducting. Then again, I suspect that most people who are claiming the fan is a bad idea haven't tested this either... or they weren't using a decent fan.

 

I think everyone agrees that ducting is very important. Of course without ducting most of the air will flow around the cooler and not help anything. The question I have is at what speed (if ever) will the fan become a restriction, assuming good ducting. Your absolutly right without testing we are all guessing.

In the case of the OP, regardless of how good the fan is ducting will make it better.

 

you all are talking about pushing air through, what about creating a short duct on the backside and having the fan PULL it through?

 

I think we are talking about the fan pulling air.

 

Whether pushing or pulling, the fan still impedes airflow. Lets assume the fan is not running... that stalled fan (or maybe its spinning a little) has a pretty good cross sectional area... its IMPEDING airflow. Now the argument people are throwing out is, well with the fan ON maybe its not....

Well guess what everyone, if the fan is on, you have already triggered the relay to activate it because the oil temp has gotten too high... now the fan is coming on trying to fix the problem caused by the fan being there in the first place

Good design? No. Well, good for low speed, and low speed only. Having a twin cooler setup with a fan on one side, and none on the other I think would be the best of both worlds But that's alot of added complexity when you could just put two efficient cores such as mocal or setrab in there. The single fan in addition to the twin cooler setup would be nice for low speed courses though, and should not affect normal or high speed driving much.

Food for thought,
Heath

 

I agree that the best case would be two high quality oil coolers, both with ducts, and a fan on one of them, and a bumper that has a larger opening to allow for more air flow though

of course, best case is also single turbo, cold air intake, v-mount upgraded radiator, extra large intercooler, an intercooler water sprayer, methanol/water injection, vented hood, a large smooth undertray, relocated battery, running evans NPG+ with water wetter

were I rich, or didn't have a mortgage, or gave up my other hobbies, then I'd probably do all of the aforementioned. Efficient dual oil cooler kits aren't cheap. They seem to run about $800-$1000+ per kit. No thanks.

I've spent $30 on my fan so far, probably $3 on sheet metal to build my duct once I do. Eventually I might install a second oil cooler using a driver side oil cooler or an ebay oil cooler, but I will absolutely not spend $800+ on a kit.

a LOT of FD owners have lots of available funds and spend a ton of money on their cars, just look at the "post pics of your FD" thread, its insane how nice some of those cars are.

Me, I prefer finding functional alternatives for less cost.

what temperatures are you running? and what kind of fans did you use. Reason I'm asking is because when I turn on my oil cooler fan, the thing is pretty much as loud, or louder than my stock rad fans :S

 

sheet metal shroud





not the best seal, should have split a length of vacuum tube along the edge to help it seal, but oh well, good enough

 

Video showing how powerful the oil cooler fan is

I have no way of measuring this but I'm pretty sure I'd have to be traveling pretty fast to generate this much pressure

and REALLLY fast for that fan to actually be a hinderance

http://www.youtube.com/watch?v=OAOgEAKHzJg

 

it's going to be a hinderance above 50mph

if you got a fan that sucked in your arm, then i'm sure you'd shut us all up

 

that is loud. you might want to seal off the edges where your shroud and cooler meet. The air gaps there will hurt - fan or no fan.

 

Itd be nice as a "flip the switch" cooling aid for track cars.

 

good thing the track I track on is a really small track and I actually don't spend a whole lot of time above 50mph (80kph). Of course, that's also in part because I'm a slow driver, but if I can manage to raise my average speed to 80kph, I'd be very pleased with myself. Right now I think less than 30% of my lap is spent above 80kph.

here's one of my laps at the track I'm prepping my car for. Mosport DDT

http://www.youtube.com/watch?v=UrOWoUtd8Kc

 

the stock oil cooler isn't the easiest to seal properly, my shroud is already against the horizontal metal bars on the cooler. I suppose I could fill in those gaps with some high temp gasket maker or something or aluminum tape, though not sure how aluminum tape will stand up to the oil cooler's temperatures

 

I would add a flange to attach window sealer to. Or use masticated rubber. Its what we use for some shields at Peterbilt.

 

BEST thing to do right now is get an oil temp gauge. Monitor temps and improve ducting or add a second cooler as needed.

Ideal oil temp is right around 212*f (waters boiling point) highest im comfortable with is 230*f, rotary likes the oil much cooler than piston motors.

 

You'd be surprised how cheap a used quality 19 or 25 row oil cooler (Setrab, Mocal) can be had on ebay. The hose & fittings are cheap from Summit Racing and Jegs. After all is said and done, you can have a working passenger cooler with lines for $200-300 dollars depending on the oil cooler and fittings/lines you chose. Just stay away from the cheap no name ebay ones.

Here's a low budget solution to seal your duct:

Get some foam tape (comes in a roll & used for sealing a/c) from the hardware and stick it on the inside of the duct. Stick it so the foam extends a little bit from the duct just enough to seal the gap. This will seal it up pretty good and since the foam is on the inside, rather than on the outside of the duct, the air wont be able to force the foam out like a flap (so to speak) and escape through there rather than go through the oil cooler.

You could also use a bicycle inner tube with some rivets & washers (so the rivet doesnt tear the rubber) and seal it from the inside in a similar fashion. This is cheaper than the foam if you have a junk inner at your disposal.

Heres some pictures I did so you can see what I mean. The neon green is the foam:

 

That video is funny.... I actually just got a dual oil cooler kit myself. With dual 25 row Earls Coolers.. THey're not ducted just yet... but i'm going to be doing that hopefully this weekend...

Just out of curiosity where'd you get that sheet metal?

- ap

 

home depot, its for household ductwork

Just a report back, just got back from the track yesterday.

No overheating problems whatsoever, temperatures were steady at 96°C throughout all of my track sessions (PFC rad fans set to come on at 95°C)

Still no oil temps, haven't figured out where I'm going to mount my sender yet, but cooling down at in the pits, my temps shoot down to 92 degrees after sitting in the pits for about 2 minutes with my heater blowing and hood open.

 

you had your fans set to come on at 95 on a track day? jeez, mine are set at 85 all the time.

 

Shrugs, I took 95 from that big fat cooling thread

7. Optimum Temps
65C (150F): too cold. According to service manual, EGR valve is non-operational below 150F, "to improve drivability when cold."
82C (180F): getting warm. Thermostat begins to open, circulating coolant through the radiator. Some coolant is still bypassing the radiator.
95C (203F): fully warm. Thermostat is fully open, not bypassing the radiator at all.
100C (212F): boiling point of pure water at atmospheric pressure.
105C (221F): getting hot. Stock ECU will activate fans to cool the car down. Fan speed will be low, or medium (if A/C is already on).
108C (226F): hot. Stock 93-95 coolant thermoswitch activates, changing fan speeds from low>> medium (or med>>high if A/C is already on) (switching to an FC thermoswitch will change this temp to 203F)


I guess "fully warm" just sounded like a good number to me lol. I'll set it to 85° once I get my laptop plugged in again.

 

I think chuck recommends setting the fan at 90, but I don't have msword on this computer yet so I'll have to check and get back too ya. Or you could get them from him yourself, they're a great reference, don't just change it on my 2 cents. I just gave my personal preference.

 

I was out at the Redline time attack this weekend out here in lancaster at Willow Springs.. and guess what?!......... Mazda trix had two oil coolers.... but they also had 2 Oil cooler fans.. haha. And that car does well over 130 down the back straight... i'm sure if they're doing it...it works.