Sergioo915

Did this to try to lower oil temp as well as to lower engine temp.
You will need:
2 6inch ATV electric cooling fan (found on ebay)
1 75amp heavy duty relay (found online or ebay)
fuse holders (appropriate gauge) (found at autozone)
Solder or connectors, 14 gauge wire and electrical tape

First, remove front bumper and remove oil cooler brackets. Jacking the car up,it will be helpful and save your back.
Remove the tab and mounting leg on one of the corners on the fan assembly.
(NOTE:be aware of mod. Once fan is altered it cannot be reurned)


Removing this tab and leg will allow the fan assembly to slide further on to the oil cooler and allow hoses to help secure the fan.

Next, drill holes on the top and bottom of fan assembly,opposite side of tab removed. Also on the top corner of fan assembly on same side of tab removed.


Secure fan to oil cooler with the mounting kit that came with fans. Using the holes drilled on the fan assebly.


Add some wire to the fan and guide towards fuse box. Wire fan to pull air through oil cooler.
More info in part 2

9krpmrx8

iTrader: (46)

Why did you make two separate threads? Are you even monitoring oil temps? Once you get some data I am sure you will find those fans to be restrictive at speed. But in traffic they will work well.

Sergioo915

Did two threads becuase I could not fit both on one thread. Do not need to montior oil temps or collect data. Trying to lower temps of any sort, oil temp or coolant temp in engine bay or in engine. These cars run hot to begin with and with temperatures is Dallas exceeding in the 108-111 any little things help. I did this mod two weeks ago and I notice quickerstart ups after running around town.. I own 2004 MT with 67,000 miles with original engine and coils. only mods are AEM intake and SOHN adapter. Pre mixing indumitsu/Lucas oil since day one of ownership. Remember HEAT is the bad, bad enemy.

dannobre

iTrader: (3)

All 9K is trying to say....without monitoring the before and after temps how do you know what you have or have not accomplished??

hoss -05

iTrader: (4)

it is my belief that it is better to run only one fan on your oil coolers that way you get some flow when sitting and the other cooler is un-restricted at speed.

bse50

Adding a fan without trimming the wheel well vents is kinda pointless. You're still blowing air against a wall.
Trimming the vents alone would probably do the trick on its own, too. Good for those on a budget or that don't do stop\go traffic only.

I actually used gauges and not a dying engine (faster warm starts? seriously? lol!) to test that stuff.

Edgar

Thanks for sharing it's what this site is all about....hey anyone in so cal do CAD i am working on a project need someone who does CAD solid works would help too

paimon.soror

iTrader: (15)

Agreed, exactly why the radiator fans shut off when you start driving. Those fans plus forced ambient air are going to create turbulance and are going to reduce the natural efficiency of the coolers. Time to read up on fluid dynamics.

On top of that, that fan is VERY resitrictive. The fact that the plate behind the motor is taking up about 50% of the surface area is going to kill cooling performance at the core of the radiator, which is the area that does the most work.

Highway8

iTrader: (11)

+1 on what other guys are saying: You need to collet before and after oil temp data, If you spend a lot of time in traffic the one fan idea would be great, other wise trimming the wheels wells is the way to go. Also, using a high performance fan would be a better idea.

I have and still am considering a oil cooler fan project but I would take a differnt route. First off I am using a single Fluidyne race oil cooler that has been coated with a heat dissipation coating.

My idea is to use one of these small but powerfull 3 (185CFM) or 4 inch (235FM) inline fans http://www.hrpworld.com/index.cfm?tp...action=product and some ducting hose to pull air from a corner of the oil cooler that normal does not get fery much air flow and duct it out of the wheel well. Basicly with my idea, there is no added restriction and you get added airflow at both low and high speeds.

If you track the car, you could add one of these little fans to both sides and use them for brake rotor cooling. Yes the air would be 200ish degrees but 200 degrees moving air is better then 100 degree static air which gets much hotter when you see 700 degree brake temps. Just a thought, I might collect some data and try some things next year.

bse50

[QUOTE=Highway8;4063867If you track the car, you could add one of these little fans to both sides and use them for brake rotor cooling. Yes the air would be 200ish degrees but 200 degrees moving air is better then 100 degree static air which gets much hotter when you see 700 degree brake temps. Just a thought, I might collect some data and try some things next year.[/QUOTE]

Brake cooling can be achieved proper ducts, no need to add mechanical\electrical parts that may fail. You can even turn our fake side "vents" into real ones. Use a pyrometer to see how well they work

Highway8

iTrader: (11)

I already opened up the wheel wells for the side vents.

Yes you dont NEED a fan for brake cooling ducts, however with a fan you have more options for your air source, no need to for a large inlet duct. Without a fan and no large inlet on the bumper to pull in pressurized air, you are better off using a small fan. These little fans are very reliable so I wouldnt be too worried about them failing. Heck for $20 each, you could keep a spare set around and replace them every few years.

bse50

Yep, the lower mouth trims can be opened to fit 2 bellmouths to host 2 52mm ducts :D
We definitely like different approaches!

Highway8

iTrader: (11)

Yes we do. My approach is take the normal tried and true method and try to tweak it to make things easier, cheaper, better or to fix a negative side effect. Sometimes i succeed, sometimes I dont.

By using a fan instead of ducting I think it will provide better cooling at lower speeds and more consistant cooling. If you pull air from behing the oil coolers you are reducing the pressure build up inside the wheel wells and therefore you should improve air flow through the oil coolers, allthough using fresh air will provide better cooling.

Pics, I am not sure I understand where you are putting them.

52MM isnt very large. You run 2 52MM (2") ducts to each spindle duct? Most spindle ducts I found run single 3", single 4" dual 3" or single 5".

BTW we got off topic and I am sorry. I introduced brake cooling with my method of oil cooling and brake cooling with 1 mod.

bse50

52mm is enough to cool the brakes, about the oil coolers i firmly believe that opening the vents is enough at anything above 20mph.
Properly reducing the positive pressure in the wheel well area also reduces lift by a certain degree (around -3mm) at 150km\h

Highway8

iTrader: (11)

Considering most people dont even need additional brake cooling, I would agree with you. I dont need brake cooling ducts, but I have heard that installing them would prolong brake pad life.

Ok, we were off topic long enough.

9krpmrx8

iTrader: (46)

Wow, so many posts


OP, I am in Texas as well and I agree 100% that heat is the enemy but if you do not know how well your mod works then it is pointless. I ditched my factory coolers in favor of a a single 28" Fluidyne unit and a proper Perma Cool oil thermostat. I was able to see the difference on my own car as well has review data from Grungepups basically stock RX-8.

We actually still kind of share data every once in a while and honestly the biggest benefit of my cooler is a quicker warm up due to the proper oil thermostat and a faster cool down time once high temps are reached. There is also a slight increase in oil pressure over stock (10psi or so) due to the larger more direct oil lines.

Now, that said, i must say that the stock coolers are pretty damn good and will work perfectly fine under 99% of the conditions an average RX-8 will see. Grungepup drives his car hard and struggles to get his oil temps above 220F in 110F+ road temps when purposely driving hard. At speed, the stock coolers work very well, and the oil temps drop fast, especially with the vents opened up in the wheel wells. But, he is reading oil temps form teh oil pan where I believe the oil to be it's hottest and his oil temps do rise significantly when he comes to a stop so if you are running stock coolers on the track, a cool down lap would be a great idea IMO.

Lastly, if you are running a SOHN then you should be running a full synthetic PAO based oil because it can handle temps to 300F+ without breaking a sweat.

I think Hoss-05 hit it on the head, if you are running stock coolers, running a fan on one of them would probably be the best compromise for a car driven in heavy traffic in the weather we see here in Texas.

Grungepup

iTrader: (2)

^+1

Yes.... I struggle to keep my oil temps above 180 when on it hard with barely any traffic, but when I am in stop and go traffic my temp will spike to 220ish, but as soon as you get moving the temps reflect pretty quickly. All the while my intake temps stay relatively 10 degrees above outside amb temp. Now the water temps can get my mind thinking about more cooling.... I have seen the coolant temps go as high at 120 while at a stop and will quickly retreat to the 105 range once under way.

So basically, data log before you make any adjustments. You might be doing more harm then good.

hoss -05

iTrader: (4)

After I get done with all my cooling and oil mods I will be data logging like a boss then I would like to test a fan on a single side one side at a time while data logging. When I figure out what side works the best I will report back.... just expect it to not happen till late this year.

9krpmrx8

iTrader: (46)

Since they run in series I would guess the passenger side one would be the best bet, that way the oil returning to the block is as cool as possible. Fan choice would be key. But honestly once you start monitoring temps, I would bet with the Racing Beat lines and increased oil pressure, it won't be necessary to run a fan.

hoss -05

iTrader: (4)

I would bet you are correct 9k, when I pull everything I want to take the coolers down to the local rad shop and have the fins straightened.

9krpmrx8

iTrader: (46)

You don't want to straighten them by hand with pick? I spent at least an hour and a half doing that when I cleaned my AC condenser.

hoss -05

iTrader: (4)

That would be a negative ghost rider....

Tamas

iTrader: (1)

Is there a link that would show how is this done? Don't remember seeing posts talking about this.

Sergioo915

WOW!!!! Thank you for your post and input. I got this idea from looking at my 88 Conquest TSI, observing the position of the oil cooler and the fan that sits right in front of it. Also looking a friends turbo deisel Ford. The 8's are not turbos, so why have a oil cooler? (1 on AT, 2 on MT).
I figured, HEAT is the reason, either to lower temps or to lengthen the life of the oil, synthentic, conventional or blend..
So lets explore this concept of heat disperesment and air resistriction, together, shall we?
Ok. So, to my understanding, there 3 forms of heat transfer or dipersement.
1. Conduction-material touching each other. (antifreeze,water in cooling system)
2. Convection-Air stream flowing over a heated surface (air flowing into radiator fins)
3. Evaporation-water or liquid evaporating taking heat with it ( sweating)
So on that note, I noticed some post stating that fan position would be restrictive at speeds but would be ok at stop.
I find a litte confusing, considering that radiator is set up the same way and with A/C condensor sitting right in front of it.
So why would do radiator set up, not be restrictive? Most cars use the 1 and 2 forms of heat transfer. I figured, increase flow through the fins would increase heat dispersment and decrease temps in the oil, which in return decrease oil temps over all.
Did gather any Data for this reason, wanted the clubs input before going and purchasing gauges and monitors (which I still will LOL).
In my opinion, this MOD will work regardless of speed and position. Air flow is air flow, the only 3 factors affecting that is temp, pattern and speed.
1. Speed that we can controll by the fan, driving and fan speed
2. Temp that can not be controlled. Temp affects air flow by increasing/decreasing the density of the air in relationship to temp.
3. Air flow is also determined by pattern. Laminar or turbulant flow.
Laminar flow, in this case is better than trbulant flow.
I will get the data as son as I can. And I did increse the vents in the wheel wells to increase
flow.
Thanks guys. LOVE this discussions. I will post some more stuff later

Highway8

iTrader: (11)

The fans will restrict airflow at speed because the fans blow air at around 15-35 MPH and generate maybe 1-2 PSI of air pressure. (these are estimates to make a point). So when you get up to speed the natural airflow will be greater then the flow generated by the fans and the fan is now acting as resistance to the natural air flow. The radiator fans on cars are typicaly designed to have low resistance, they do this by having smaller and less fins.

Radiator fans on cars typical cover a surface area which is atleast twice the size of the grill opening, so if those fans can move air at 35 MPH, they wont have any resitance to natural airflow until the vehicle reaches atleast 70 MPH. Over 70 the fans might restrict airflow by 10-20% but with engine load being so low at cruising speeds, its never an issue.

To the RX8 oil coolers. The oil coolers are designed to maximize its effeciency by exposing about 80 % of its face to air flow so placing a fan behind it will become restrictive much earlier. Additional, a small fan is typicaly very restictive maybe 40-50% which makes the problem even worse.