Shrek's new DD - 03 Evo VIII

[Shrek]

I know I don’t want it running all the time. I just wish I knew what this box did and how to remove it while keeping the cars functionality. I think the fan works at different speeds depending on what the ECM tells it.

Here are the fan circuit diagrams from the manual:

AMS’s directions say to just keep it and cut the stock plug off the stock fan…

@crazybaldhead"

The box works like this:

it takes a signal from your coolant temp sensor on the head, near the thermostat, figures out if your car is moving or not and switches the engine fan on slow speed only at 92 deg C (in a VII) if the temp gets to 97-98, then both fans come on at high speed until temps are less than 91 deg C.

(I live in Trinidad and it gets to 32-34 deg C here every day)

if you turn on your AC it bypasses this controller and puts on the fans on high speed regularly and the engine temps hover around 85-90 de C.

If you bypass the box and run the fan on all the time the following will happen:

You will lose power due to parasitic drag on your alternator.

Your battery and Alternator will not last as long as they should

Mileage will decrease.

Your fan may not last very long either. On a cool morning with no stops for traffic in my 30 min commute the fans may never even come on. Now imagine the fan being on all the time, it puts much more wear on the fan.

lastly, the car will actually run HOTTER at highway speed that if the fan were cutting out and coning on as it should.

@bruce988jl"

Well I guess I could chime in on this. I work for Bosch Automotive and do testing with radiator fans and motors so yea…

I’m not sure exactly about the one on our cars (lancers alike) but I believe its a PWM, pulse width modulator that basically has a bunch of high current transistors that allow it to regulate the speed of the radiator fan at any given time. So it takes the 12v going in and runs it through the transistors at a high switching frequency allowing for the ECU to control what speed the fan spins at. Technically if you bypass it the fan would just constantly stay on at max speed.

Keep in mind this is based off the Bosch FCM (Fan Control Modules) that I’ve dealt with…

Hope that helps…?

@barneyb"

The OEM fan, the one on the driver’s side, is variable speed. The box is the controller.

Have been looking for this info for two days. Thanks

I would like to remove this control box but sounds important in a DD.

Was thinking you could use the signal wire from the ECM to trigger a relay to the fan?

[neonglh]

That would be the easiest way, but then it’s full weight still, heh.

[Shrek]

Not being used so removed!

Then

[Saxon]

Ur going crazy on it, personally I love the fact that the car doesn’t sound like a tin can, but I guess these things rattle when new anyways lol

[KhoiFish]

that cleans up nicely!

[nytalonTSi]

Whoa. Lol, cool.

[neonglh]

If you get rid of airbags (not that I say you should, but if you do), you can get rid of those 2 sensors by the shifter, the control box in front of the shifter, the 2 sensors under the hood, and the airbags themselves. Lots of weight, but then you lose the safety, heh.

[Shrek]

Air bags are staying this year. I really wasn’t able to find much weight to lose under the dash? Between the sound detaining and fire wall rubber Id guess close to 20lbs!

What would be your guys opinion on getting 5 point harness and a harness bar? Weight / safety wise??

Dry ice is in doing its job while I type!

[neonglh]

You can cut some of the brackets off of the dash bar, that would add up to a pound or two.

[Shrek]

That dash is crazy heavy. The seats are also heavy.

Finished removing all the insulation behind the dash, sound detaining from the floor and I also removed all the padding from under the carpet along with the wood and steel plates. This wasn’t a very fun job but I feel good about it. Just the fact that I know the car is cleaner and a little lighter makes the job worth the two days I spent on it.

I spent 25 bucks on Dry Ice and I can safely guess I removed 20lbs.

[Shrek]

@Shrek

40# lighter than the stock!

Before

After

Obversely its a little to low, thats tomorrow job. Try to get the alignment as close as I can and the hight to a reasonable level.

New toy I mean Tool!

[KhoiFish]

Awesome!

[Saxon]

Looks so much better without gap, I want to do a full coilover but can’t justify 2000 for a shittier ride quality

[91MR2]

Nice progress…

[Shockwave179]

Good progress, looks a little too slammed IMHO.

[neonglh]

@Saxon

Looks so much better without gap, I want to do a full coilover but can’t justify 2000 for a shittier ride quality

I have found that the coilovers ride a lot smoother than stock on Evos. You may want to try it before you assume it’s shittier. Soft setting on D2’s, Megans, etc… are way more comfy than the stock strut.

[Shrek]

WTB: heater a/c control assembly

Mine broke - Need this

Or just

82006 and 86314D?

LMK!

Thanks

[deebo]

there’s no such thing as too low

[nytalonTSi]

Best way to get another hvac would be on evom. Find someone parting out an evo.

@deebo

there’s no such thing as too low

Evo’s that are slammed ride like garbage. They look perfect and ride great with just getting rid of the wheel gap. :tup:

[Saxon]

@neonglh

I have found that the coilovers ride a lot smoother than stock on Evos. You may want to try it before you assume it’s shittier. Soft setting on D2’s, Megans, etc… are way more comfy than the stock strut.

I guess i will have to get a ride in someones Evo that has a full coilover, every set of Megan etc that I’ve seen hondas ride like junk so that’s why I thought they would on an Evo, thanks for the info though might have saved me some money