TMIC fan mod Q&A

This post will be updated as we go. Since this thread can go in two ways, I will leave the option be.

Alrighty, up for discussion is the fan mod I did today:





Now discuss! Some are saying it will impede air from getting through and whatnot. George had them on his car:



We will wait and see what he has to say about how he made them work and the theory behind them. :tup:

Now, I don't possess the knowledge you guys do, but from a common sense perspective... wouldn't the fans suck in air from right outside the scoop; the air that is not hot like the one in the engine bay? That is how I see this working. I just didn't know how to hook it up electrically so the fans are on. When looking at George's set up, I see both fan wires hooking up together into one splice, connecting to the tap which acts as a grounding??? I can't determine the rest and I can't understand it either! What do you guys see in his set up? How did it work?

He stated that he had some kind of temperature control to turn the fans on when the temps under the hood reached over 100 degrees. According to his picture, I don't see how the wires are hooked up to any controls??? It was suggested that I hook mine up to a power source so that when the car is on, the fans are also on. I like that idea as it isn't as complex as the temperature control modulator.

Looking forward to understanding this and learning more about it! :bigtup:

My first question is: why do you think that you need this? I guess it'll help around the city when you're constantly stopped, but if you're moving regularly, it'll just hinder airflow and add weight. But unless you're doing lots of racing off long stoplights, whats the point? Why not just use the IC sprayer?

I found one guy that managed to get the fans to put in airflow equivalent of going 100 mph. I dont remember what the exact cfm was.

Im still waiting on George to talk about his set up.

I took off my heat shield, i dont go over 90 anymore and if i do its pretty rare. Fastest on highway is about 75/80. Mainly city driving. Plus it looks sweet and definitely unique.

By all means if George had a crazy complicated set up and i am not able to make the fans work, they will be taken off.

Ive been reading on different forums about people who have done it, people who have flamed the people who have had the fans on, and people downright saying it wouldnt work.

Lets see whats to be said about it.

Here is the relay i found for the set up:

http://www.the-fan-man.com/shop/frh-p-99.html?cPath=30

I'm interested in seeing how well it works, been thinking about the same type of setup off and on for the last 3 years. Yeah, adds a little weight, but if you're stuck in town with lots of traffic you can "feel" the car getting more and more sluggish as it progresses, even worse down here in hEll Paso than it was up in DC (temp-wise and idiot-driver-wise, not traffic-wise).

Wiring wouldn't be that hard. You could show me what you have to work with and I might be able to draw you a schematic and procedure.

That works. Sec

It may take me a day or two to finish it btw.

So those two cables i wrapped in electrical tape for the time being.

There were several reasons why I chose to do this. The primary reason is because of the design of the intercooler itself and the other reason was because I removed the factory duct work when I replace my hood with a carbon hood and temps under and around the intercooler were getting unruly. I was also using this in conjunction with the IC sprayer and I will explain that trick in a bit.

So what did the design of the IC have to do with it? The stock IC is a tube and fin design and flow through the fins is fairly efficient and the tubes are far apart allowing better flow and movement of air. My IC (and Alin's) is a bar and fin design and the gap between the bars is smaller making flow through the IC less than desirable. It seemed the only way to solve that problem was to force air through the IC with a fan. Some have mentioned to me that the fans them selves are restrictive when turned off but I have not noticed a difference in IC output temps with or without the fans in place. So I think it is negligible. The characteristics of these IC's are such that they flow high volumes of boost but are not very efficient because of the bar and fin design which makes them not much better than the stock IC. But when you couple them with the fans they become very efficient. With the fans on, the out put temps of the IC were only a few degrees above the temperature of the air at the inlet of the turbo. With the fans off it was significantly higher with only a few degrees of delta between the output of the turbo and the output of the IC.

Also since we are using an after market hood and scoop, the flow of air through the engine compartment has changed significantly so the fans are almost necessary especially in traffic or low speed driving. When using the IC sprayer, the fans do a really nice job of distributing and atomizing the water for a much more even distribution over the entire IC surface. This is where the fans really came into there own. The way I did this was to spray the water right down onto the spinning fan.

As for the temp control, I built a simple module that switched a relay on when temperature under the hood reached 100* or when temps under the IC reached 140*. Either of which could happen during slow speeds or in traffic. The module also looked for signal from the IC sprayer switch and turned the fans on when the IC spray was activated.

George.

George, did you have the same fans on your set up?

The ones i got are:

Size: 10"
RPM: 2200
CFM: 1550

Someone else on a different forum said going 100mph is equivalent to 250 CFM with the stock splitter and TMIC.

That seems really low if these fans are rated at 1550!!!

I don't know but I do know they were more than sufficient

Ok, so I misread that 250CFM thing for 100mph.....so let's disregard that. The only thing I could find that's remotely good information was from socalsubies:

Vanna White:

Welcome....Pretty interesting intro.

As in other threads, and designs, have you tried the Air>Fan>Spray>IC test already? if so did your results differ from your current Air>fan>IC? any dyno graphs to shown any improvement in awhp? BFC?

why do you feel you'd be more successful then companies like zerosports? and cobb with your design?


In my "lamens quick analysis," I think it makes sense.

A: Radiator = heat exchanger ( radiator has fan )

B: A/C Condensor = Heat exchanger ( Condensor has fan )

C: Intercooler = heat exchanger ( let's add a fan )
other folks have also done this on a larger scale...........

http://www.speedindustry.biz/porsche.html

http://www.iwsti.com/forums/3573240-post3.html

The issue with the whole idea is, that there are many other practical ways to battle soak. Is it a totally worthless Idea surely not, especially if there's inadequate cooling, and even slight improvements..

These test results just correlate that @ idle the 3 fans create 500+CFM and the cfm decrease as the oncoming air charge increases. No car really stays at idle forever and 20-40mph really only happens while on the street or in a rush hour traffic jam.

Idle: 530% more CFM
10mph 202% more CFM
20mph 72% more CFM
30mph 50% more CFM
40mph 22% more CFM
50mph 10% more CFM
60mph 8% more CFM
70mph 7% more CFM
80mph 7% more CFM
85mph 7% more CFM


If there were more pros noted than just flow, like improved fuel economy, low end TQ or HP, reduced combustion temps, improved spool times, something concrete proving the benefits, I'm sure this would be a hot item. Ideally this reminds me of echargers on ebay.

If it sounds like I'm playing both sides, I am, I'm on the fence with this product. It makes sense, but there's just not enough supporting UMPH to back why it's a worth wild purchase!


Kndcat:

Very smart analysis Vanna White,
You sound like an engineer. Thanks!
I hav'nt tried a water spray in conjunction with the fans, but I have some ideas about that. I think the fans could distribute the mist more equally.
If zero sports or cobb had this product I think they could sell it without having anyone question any stats, tests, etc. They have a solid reputation. No one has heard of me.
I don't have any dyno data. No money for that. Times are tough. Laid off a while back and looking for a job now. The dyno test I reference in my auction are an observation(s) I have made watching dyno videos. It see
ms to me in the tests that:
A run is performed.
The car is then allowed to idle for 30 seconds-2 minutes.
Run # 2 is performed.
Data analyzed.
This type of test might be good for a exhust, intake, crank pully, etc.
But I question it for an intercooler test. The intercooler might perform better tested when allowed to 'rest' between runs.
I have no proof to back up these thoughts. Just my speculation.
Also, does any dyno have a wind speed emulator to connect to a floor fan? So the wind speed is relative to the dyno mph? I
don't know.
Hey, would anyone in the group be willing to do a free dyno test?
That would be sweet :-}

Here's the thread: http://www.socalsubies.com/forums/showthread.php?t=16608
On a side note, if you search "sti tmic fans" we are on page 2! :lol: (Maybe because there's not too many)

The fans that most people were using were 4-5" big.... Those are some small ass fans!!!?????

Why would someone use such a small fan? How big is the stock tmic from top to bottom where it connects to the intake manifold?

Now i can see why people were saying its ineffective to use them. You arent pushing shit with a measely 4" computer fan! :lol:

George also has a close up shot of the BPV in his "how to replace your clutch in your driveway" write up and i still cant determine what the wires are hooked up to!

My power source was a fuse with switched power from the fuse box under the hood.

They claim these fans are 1200 cfm

HolyCrapItsFast said:

My power source was a fuse with switched power from the fuse box under the hood.

They claim these fans are 1200 cfm

Click to expand...

How did you route the two fans together to the fusebox? The picture i was looking at was Fig 3. You have both fan wires meeting in the center of the intercooler hooked together. From there on i cant determine what follows. I assume its just one wire leading to the fuse box. Did you have a custom "on/off" switch implemented in the car?

Im thinking about getting rid of my fog lights and switch. That was i can get my own "on/off" switch in that spot.

However... I would like it if the fans were on at all times while the car is on. That would be ideal for now.

Do you know if the fans use any significant amount of power to while on? I know it says the voltage on the top, but i have no clue what that means in terms of power usage.

As long as its safe to keep them on while the car is on, ill be happy.

Okay so here's what I have come up with for you. I am making an Arduino controller for your fans and I have made significant progress. I have all of the logic worked out and tests flawlessly on the bench. I have all the hardware selected and am ready to build the prototype.

Features...

- Two sensor input using TMP36 sensors
- RGB back lite 2x16 lcd display
- Stand alone 3bar MAP sensor input using GM MAP sensor
- 3 channel high current outputs - Fan 1, Fan 2, IC Spray
- Push button to activate IC Spray on-demand
- Remote display unit

Functions...

- Opening ceremony
- Display shows temperatures and fans status and IC spray function
- Fans and IC spray operate independently under various temperature and boost conditions
- Fan 1 comes on when temp 1 (engine compartment) is greater than 100* (Green back light)
- Fan 1 and 2 come on when temp 2 (IC heat soak) is greater than 135* but less than 145* (Yellow back light)
- Fan 1 and 2 and IC spray come on when temp 2 is greater than 145* (Red back light)
- Fan 1 and 2 come on when boost is greater than 3psi regardless of temp (Yellow back light)
- Fan 1 and 2 and IC spray come on when boost is greater than 10psi regardless of temp (Red back light)
- All fans off when temp and boost below thresholds (Blue back light)

Holy crap that's awesome! Is there going to be anything that I need to do on my end besides installing the fans? (Which I already did) :bigtup: :ty:

[MENTION=9]HolyCrapItsFast[/MENTION] I'm loving the innovativeness with the arduino controllers. Can't wait to see the outcome of this one too!

black bandit said:

@HolyCrapItsFast I'm loving the innovativeness with the arduino controllers. Can't wait to see the outcome of this one too!

Click to expand...

Thank you! there is a world of stuff you can do. Just about anything you can think of.

Alin said:

Holy crap that's awesome! Is there going to be anything that I need to do on my end besides installing the fans? (Which I already did) :bigtup: :ty:

Click to expand...

Just install it. I will make it as simple as possible but it is no harder than hooking up a car stereo or a set of speakers. The hardest part is going to be tapping into the IC Spray system.