Oil cooler core size/analysis... Suggestions?

[Cory]

The first modification I will be performing on my car when I return is a drain of the current 10w-40 high mileage Mobil 1, installation of an oil cooler, and a fill of 5w-40 Redline. Currently, I have a heat exchanger sitting at home that is identical to the exchanger that Def runs. It is labeled as "Tru-cool" on the box. I am kind of questioning whether or not I should use a different core. Setrab seems to have an upstanding reputation amongst most car enthusiasts. I plan to return to the states with a lot of paychecks in the bank considering there is nowhere to spend money in the ocean aside from the internets. I obviously plan to duct whatever cooler I have. Def, I know you have stated that your cooler works well, which does ease my mind some. I just don't want to be tearing this crap apart again in the near future because my oil temps are going up.

The sizing guide that SPL has does not create too clear of a picture as far as what I should be looking for. Obviously displacement/dimensions is about as accurate as you can depict something with numbers, but I am not quite sure what size I should go with. I drive the race line pretty much anywhere I go and floor my car a lot. My track days are normally only these private track rentals which give each participant unlimited track time (virtually) just to give you an idea of the usage of my car. A couple nights out of the week are usually spent doing pretty spirited driving, both straight line and handling, and I live in Florida. The car will remain on 14psi (~350whp) for quite a while.

Any advice/analysis/experience is appreciated, preferably with data/pictures. Thanks!

[2Fass240us]

What size is the Tru-Cool? I have one on my car and it's not like it's a bad product. One reason it's cheaper is the company (Long, IIRC) makes a lot of OE coolers.

It would be hard to tell you how much heat you need to remove without knowing what you oil temps are.

[Def]

Why do you think the Tru-Cool core won't work for you?

I've posted up my experience before, with instrumented oil temps in the pan. Just to put it briefly, I was coasting on straights before with oil temps going above 250 deg F and water temps rising quickly(215) when it was 80-85 deg F. 90 deg F track day with the core, no ducting, just the stock headlight hole in the bumper and I was seeing 200-205 deg F in the pan with 15 psi and not letting up at all. Water temps dropped down to about 190 deg F with the same radiator/everything.

Hard to argue with that.

I imagine with some easy ducting I could drop oil temps more, but I see no need given my previous experience.


BTW - increasing fin density will increase core resistance to flow. The Tru-Cool is a relatively easy design to manufacture(hence the cost), and trades cramming the most surface area in a given space with a more free-flowing core. So you might see "ohhh... a core with more fins," but keep in mind that flow will be restricted through them, so it's not as much of a "no brainer" as it may seem.

I've had some experience designing heat sinks/heat dissipation systems, and the B&M stuff is very nice for the application - especially for the price.

[Cory]

It is Long, I couldn't remember the name off hand.

I have no data thus far on oil temps. Unfortunately, a crude indication that I need a cooler bad is on relatively cool nights, a couple runs up to about ~150mph WOT yields a 4-5psi pressure drop at idle. After I turn the car off for 20-30 minutes, I have original oil pressure.

These two posts are more conclusive. I will stick with the Tru-cool core.

As far as placement, I plan to duct the intercooler/radiator much better than it currently is. Given the assumption that air will follow the path of least resistance here, how effective would you think placing the oil cooler in front of both the intercooler and radiator would be? Currently, I plan to use the stock foglight holes for front brake ducting, so I can't really use either of those. Installing the cooler in front of both the intercooler and radiator should be sufficient correct?

[2Fass240us]

Check out my setup here. This is arguably the best placement on a S-chassis, assuming you no longer have the stupid battery tray to deal with. This will yield pretty good flow, despite the brake ducting trade-off. I decided not to worry about the brake ducting issue because I have a SMIC on the driver's side that pretty much messes that up.

The best brake "ducting" option in my case might be SPL TC rods with optional brake deflectors. jmauld is also hunting down an OE solution.

It is also my opinion that airflow is already too disrupted in FMIC cars to put the cooler between it and the radiator. This is one of many major flaws with common FMIC placement.

[Cory]

I can't go without brake ducting any longer...hehe

I am not going place the oil cooler between the FMIC and radiator. I am going to place it in front of both the intercooler and radiator. I believe I will do this method with a separate duct inside of the ducting to the FMIC and radiator. The oil cooler duct will simply be a divider plate ensuring that air cannot go around the oil cooler core, similar to divider plates inside of intercoolers that ensure the entire core is being used, rather than just the lower half of the core. It kind of seems like overkill when I think about it, but I would really like to turn the final bolt on my engine with these next few modifications and simply change the oil for a little while.

[2Fass240us]

I am not going place the oil cooler between the FMIC and radiator. I am going to place it in front of both the intercooler and radiator. I believe I will do this method with a separate duct inside of the ducting to the FMIC and radiator.

You are still robbing the radiator of airflow, are you not?

[Def]

I have mine in front of the pass tire. I'd go there if you can stand to lose your washer nozzles. Just cut a new hole for ducting.

[turtl631]

Judy? Putting the gf to work Def?

[Def]

haha.. her name is Brittany, but I see the iPhone was getting clever with its predictive text.

Unfortunately NRR is blocked at work. Which BTW Richard, you might want to check if any common "net nanny" programs are flagging NRR as something bad. I hear all you have to do is send them an email and tell them it's an information/educational site for cars and they'll unblock it.

[Cory]

You are still robbing the radiator of airflow, are you not?

Well, not necessarily. The air that passes through the oil cooler core will be hotter than the rest of the air entering the FMIC/radiator. I can easily compensate for this by making the entrance to the FMIC and radiator a little larger. An entrance that is about 25% of the size of the surface area of the heat exchanger is typically adequate so long as it is ducted well.

...

My washer resovoir is already gone. I want to use that opening for brake ducting though. If there isn't enough room at full lock for brake ducting, then I will probably use that area and use the brake deflectors from SPL.

[Def]

You can squeeze a duct past the core. Mount thecore at an angle to the flow to getmore space.