Black & Green modding thread (1998 Civic DX Coupe base)

[California98Civic]

Originally Posted by jedi_sol

if CA98civic doesnt mind me answering for him

hahaha! Yeah, that's fine.

Originally Posted by jedi_sol

It doesn't make any difference in mpg if his battery is draining faster than normal.

it's cuz he is running with no alternator, therefore, battery drain is extremely important to track. You simply just dont want to be stuck in a parking lot or on the side of the road because your battery has no more juice

am i right, CA98civic?

I run without the alt, generally, though I do turn it on for braking assist sometimes. I also run it whenever the battery voltage under load drops close to 12.1 or 12.2 (to preserve longterm battery life). The switch is an awesome benefit for this. This means, of course, that a lot of fan use will reduce the battery level and force me to run the alt sooner than I might have, thususing more fuel.

Originally Posted by johnlvs2run

To rephrase, as I'm having a similar issue with the fan, how much difference could this be making with my mpg?

I wish I knew for sure. Assume you're losing maybe 1 HP to a running electric fan, which has to get its power from the battery, which means ultimately the alternator and gasoline. The HP loss might be less. If it takes about 10 HP to propel a little Civic like ours along the freeway, 1 HP is about 10%. Looked at differently, MetroMPG ran a test and posted the results here in which he happened to see a 10% fuel economy difference with and without an alt. Our Civics are different we have OEM electric load detectors that help the ECU control alternator output according to charging needs and driving conditions. Our cars sometimes shut the alt off by design. That said, I thought I saw a 3-5% difference when I was experimenting, but I did no ABA testing.

In short, I don't know how many MPG it costs, but I prefer to keep the fan off as much as if safely possible.

Does anyone know how much power the fan actually draws? 100 watts, 50 watts?

[Daox]

I think when I measured mine on my Paseo it was 7-8 amps. A quick google search tends to agree:

How many AMPS does a stock civic radiator fan pull? - Honda-Tech

Mine pulls 8.1 amps

You also have to think about motor brush wear. I've never had to replace a motor or brushes on any of my cars, but I have had to do it on someone elses car. It was a Saturn. In that case though, the coolant temp sensor wire was severed, and it was running the fan all the time until it wore the brushes down to nothing.

[jcp123]

Fan drain is decently high; when I was in Dallas last week, I had the a/c on the whole time (meaning rad/condenser fan was always on), and I could hear the alternator whine as it was constantly fielded. Without the fan running I normally only hear it whine/charge like that after I shut down at stoplights and restart.

[California98Civic]

Gosh, using an ohm's law calculator that's approximately 95-100 watts, depending on voltage levels and amps. If about 750watts equals 1 HP, then 100 watts is approximately 0.13 HP. Normally, I replace that power from the grid, which is why, if you look at my fuel log you'll see I have seen quite a dip in my miles/kwh calculations. And after my battery runs down to the point where I turn on the alt, power is generated at maybe 25% efficiency. So the equivalent of about 0.5 HP, or about 5% of the power needed to sustain cruising speeds on the freeway, unless I am mistaken. In other words, if I could reduce that power drain without negatively effecting aero (too much grill blocking removed) or adding too much weight (in batteries), I could net some further gain, maybe pretty small, but something. And so, solar panels come to mind again... again.

[PaleMelanesian]

Kill-a-watt. It's like a scangauge for your wall socket.
http://www.amazon.com/P3-P4400-Elect...ds=kill+a+watt

[California98Civic]

Originally Posted by PaleMelanesian

Kill-a-watt. It's like a scangauge for your wall socket.
P3 P4400 Kill A Watt Electricity Usage Monitor - Low Temperature Alarms - Amazon.com

Yeah, I already use one. I bought it for house diagnostics and mods, but with those done, I moved it into the car. It stays plugged into my onboard charger, which is behind the driver seat. Whenever I plu in to charge the car battery the kilawatt records my usage, and I track it--as you do--in my fuel log, breaking it down to miles/kwh. That's how I discovered the summer electric use spike is quite significant.

[California98Civic]

1. Undertray progress
Completed the rear diffuser template:


Cut from a roadkill diffuser the small venting holes I plan to use on my own diffuser, if possible:

My 25' roll of 2 or 3 mm thick x 22" wide black plastic arrived!


2. Frontend frustrations
I gave up on the road kill bumper cover and recycled it, after cutting lots of bits off without finding a way in which I would contribute usefully to lowering the stagnation point:


3. Interior mods progress
This was fun... I made a new center console panel using my daughter's throw away old looseleaf binder, bits of hardware I have saved, a box of mints, plasti-dip, a used gen 2 iPod touch, and some other random stuff. I bought nothing but the iPod Touch ($50) and the drill attachment for cutting the circular holes.

Using a little CAD I made a template of the shape I needed, then used it to cut the daughter's old notebook. Then I cut holes for mounting ultragauge, iPod Touch, and a USB port (as well as conduit lines so the wires car run through the panel into the dash:


Painted with black plasti dip, four layers:


Metal conduit for iPod wires, UG bracket, and USB port in place:


Mint box, cut to serve as iPod Touch stand:


Drilled and painted with plasti dip, four layers:


Completed installation:

[nemo]

Great idea for a phone holder.

[deejaaa]

too cool!

[California98Civic]

Using this graph to determine the best angle for my type of rear diffuser (which will start just behind the axle)...



Then using this method/formula from aerohead (in another thread)...

Originally Posted by aerohead

*You do need to be on a flat level surface
*You should have 300-lbs of ballast in the front seats so the car will have its 'driving' inclination
*Locate the spot where your diffuser will begin
*Measure its elevation above the ground
*Then measure back to where the diffuser will terminate to get your horizontal distance,your 'run.'
*If you have a scientific calculator,you can use the trigonometric function to get your dimension multiplier
*If say,you do use 4-degrees,enter: 4 tan,to get 0.069926.
*If you multiply your 'run' dimension by this value,it will give you your 'rise' at the back of the diffuser for 4-degrees.
*This will be the exact distance above your original starting elevation for the rear of the diffuser,to get your 4-degree slope.

I went to my nearby beach spot with the super flat parking lot, and to the flattest spot of it, "checked" with a 4' level (hahaha!)... I loaded up with "balast" and took these measurements:

I got 7.5 inches clearance for the low part of these reused "mounts" and 9.0 inches if I bolt directly to the axle assembly

The pics are just for illustration, not precise representation of the measures.

I got 28.5" for the short diffuser option and 30" for the longer option (subtract 1" from what's seen in the pic.)


Then I calculated using the method aerohead describes:

4* (tan4)


Times a 28.5" run:


Times a 30" run:


So depending on whether I go with 28.5" or 30" long diffuser run, a 2.098" rise from level at the trailing edge of the diffuser or a 1.99" rise will give me the 4* angle I want. Now I'll look for the best way to attach this before I cut the plastic from the cardboard template.