5th generation civic hatchback - improving aerodynamics

[Sandy]

I've noticed now that the headlights don't need to be on during my commute,
that the Civic's battery voltage is generally at 14.1 or so,
but every now and then it drops to 12.2 or so.
At first I thought it was the sign of the charger going bad,
but know I'm beginning to think it's just cycling charge as needed.

[aerohead]

Yes,the "airdam" didn't show up 'til 1963,with it's debut as the "modesty panel" on the Corvair.Hoerner would have known no such term.

[aerohead]

Sorry! I just now discovered all the additional pages on Andrew's project.Time for my big self-administered head-slap.Ouch! And your right.If the numbers show drag reduction,its a reduction,regardless of the frontal area.And I can't speculate on what C and D's logic was back in '74,to make the dam so low,so I'll hush and just respect the numbers for what they are.The CIVIC nose may project further forward than the Pinto's,so Andrew may have to watch speed closer on driveway approaches.

[aerohead]

Originally Posted by .Cd

Hey Darin. I must have bad Karma or something as far as trying to copy your work.


My main snag has been getting the spoiler to slope downward. I'm using thin ABS plastic just as you have.
Whenever I attach the sides of the spoiler, the ABS has a natural tendency to bulge upwards in the center, and I loose all of the sloping angle.

I just can't figure out how you got the plastic to slope without having the sides bulge or vise versa.

I've completely ran out of time on my vacation and it looks as if I may have to even cancel doing any kind of tuft testing.

Family comes first and all

I'll post pictures of my ........ failed..attempts.

Your work has me envious. ( I was trying to imitate it, and as the saying goes, imitation is the sicerest form of flattery.

Looking very forward to the new results !

.Cd,for the interface between the cabin back and boat shell on the T-100 I ran into same challenge.Since I was trying to deform my plastic sheeting in two dimensions simultaneously,it was continuously buckling! All I could think to do was,try and ascertain where the buckling was beginning,then drill and then slit the plastic all the way back to relieve the stress.This meant a lot of overlapping and unsightly seams which I "shingled" over each other for rain control.Compound curves are the toughest to form.Fiberglass would have made a good job,but didn't have the time.I understand your frustration,especially when the clock is ticking.Try and laugh it off if you can.I appreciate all the members attempts at mods,even when they backfire,and boy have I had my share of those.

[aerohead]

Originally Posted by avitet

assuming you have a 1.5 which makes 70 hp at sea level you only have 33 at 1800 ft sorry if someone else has already made this statement i havent reached the end of the thread yet http://www.webcalc.net/calc/0757.php

Pardon my butting in,however I believe that the power would fall off to 33-Bhp at 18,000-feet elevation,not 1,800.

[AndrewJ]

I just got this in the mail today:
A 100 amp ANL fuse and fuse-block for the batteries. Make sure to have one of these installed when you do a battery re-location kids!






You should always have a fuse installed within 16 inches of the batterie(s) when adding an additional main-power-wire to your car. (the same rule as applies to car audio amplifiers and such)

That way if something ever happens and the wire shorts to ground the fuse will blow instead of lighting your car on fire


Anyway, I also messed around with a little bit of ABS and a peice of cut-to-fit mirror "glass" that I got at the auto-parts store.
I decided to make a (very) little side mirror just to make sure I'm in compliance with the law. That and I kinda miss having a side mirror, they're handy.








Running beltless (with the alternator) seems to be working out swell. I've been able to go two days without the alt. I have definately noticed the reduced load on the engine at cruising speed.
I don't have to press as far down on the gas pedal as normal, it's almost like before I installed the HAI.

The batteries are holding up OK, but then again I haven't had to commute in the early morning when I'd have to use the headlights. Even using the radio reduces the "range" of my batteries noticably.
I'm thinking of investing in some new batteries. The payback period would be about 3500 miles....

We'll see how this latest de-sulphation goes. Maybe it'll get me that extra capacity I need.

[boxchain]

Great stuff AndrewJ!

It doesn't sound like the alt cutoff is working, but with 2 ways to charge the batts, beltless might be the way to go.

Thought about cleaning up the air around the solar panel with some nice wide tape?

[AndrewJ]

yeah, I've been thinking about sinking the solar panel down so it's flush with some 1/2 spacers or something.

It'll have to wait till Monday...

Lots of stuff is getting done on Monday, I only have 6 days left to get ready for the MPG rally in Lacey, Washington!

I gotta go show all those CMPG folks how we roll.

[mimsmetro]

what are your front tire dimensions?

[MetroMPG]

Originally Posted by AndrewJ

So I filled up the tank today for a whopping 49mpg.
Dissapointing to say the least, especially for the first full tank with the alternator-switch. The alternator was switched "off" for about 80% of the tank.

Yeah, that's a bit perplexing.

Were there any other changes? Had you somehow adjusted your driving style thinking alternator-off was compensating?

You need a MPGuino! (Did I miss the latest chapter in the SuperMID build? What happened there?)