Is 42mpg too low a goal?

[Wonderboy]

Oh, and Wonderboy, I think you might be attributing more reference powers to me than I deserve. I wanted to put "is not currently covered in bees." (but it wouldn't fit) because it is silly and tends to lead people to mistakenly assume that I have been covered in bees at some point in the past, or will be in the near future. (neither of which is the case, to my knowledge)

I was talking about your avatar which appears (to me) to be a flaming Pi. (flaming pie is an album). I personally don't like Paul McCartney, especially now... but to each his own. I guess that's not what you were going for though.

[evolutionmovement]

What about cutting the bottom radius off a junk yard bumper cover and using that underneath? Even still has a lip underneath to attach the undertray to. FYI, if you have a plastic welder and want to play with it, the bumpers are polypropylene.

[MetroMPG]

A traditional (flat plate) splitter could still cause separation if it's not the right size (length) out from the bottom.

Originally Posted by Istas

An inch-diameter foam cylinder, sliced in half lengthwise and running even along the bottom edge of the airdam.

I'd bet on that idea being a decent fix.

[Istas]

I'd thought of the splitter, QuickLTD, but there's a few reasons I wouldn't want to do that. The primary one is that it would be very vulnerable to bending/damage, and it would need support to help prevent this. Second, it would further reduce ground clearance in the front when starting up an incline or into a driveway or whatnot. Third, it would shove more air into the radiator and now that the partial undertray is on I think that's worse than letting it go under. And I didn't even know about the proper length thing. It would definitely look cool though, and be fun/relatively easy to make.

evo-move: I'd thought of that too, actually. I was thinking of cutting off the bottom lip of another bumper from a junkyard, then shortening the airdam by its height and attaching it to the airdam, then trimming the edge of the undertray to fit the piece of bumper and attaching it to that. That way it wouldn't be putting anything further down into the airflow. But that's a lot more work than the foam option, and right now I don't feel like tearing apart something I just built, with only 5 days until going home and my MPGuino not yet hooked up, let alone calibrated. (and I don't know where a junkyard is around here, let alone one that would have a first-gen Legacy. There's one maybe 45 minutes from home back east though, with several to choose from)

I've also pondered just doing bends in the airdam itself, but that's also a lot of work. As cheap, quick, and easy as the foam half-cylinder is, I think I'm going to go with that for now.

Anyone have any recommendations for the type of glue to use for that? I don't want it falling off, either.

Wonderboy: Ahhh, heh, that's a weird name for an album. Of course, I like weird names for albums. But no, I didn't do it in reference to that, at least, not consciously. I was on a road trip/vacation with my father, and we had three of those wax-wood "starter log" bricks left over. I wanted the entertainment of burning them instead of just leaving them somewhere, and that was the most creative shape I could come up with. Cool coincidence though.

[QuickLTD]

how are you going to mount the foam? Not how it will be attached but what are you going to make it look like? A 90deg radius from front to bottom?

[Istas]

It'll be a foam cylinder cut in half lengthwise, with the flat half of it adhered to the airdam.

Put some deflectors on the back of the tray so the wheels don't scoop mud up onto it. I guess it might help isolate that whirlwind of air kicked up by the front wheels.


I got the MPGuino hooked up, and it functions! I'm very excited about this. The only problem is I mistakenly hooked the power source to the stereo power supply, which is not always on. At least I don't have to mess with the VSS again. I'll work on that tomorrow.

[Istas]

Oh, and after looking on that forum that evo-move suggested, I'm now fairly sure that there is a speedometer cable running from the transmission to the instrument cluster, and that there is a device in the instrument cluster that turns the speedometer cable movement into an electrical signal, that is then sent to the ECU and whatever other devices need it. Which makes me worry once again about the speedometer sticking, and affecting the MPGuino data. (fortunately when I've seen it happen it doesn't last for too much of an extended period, so hopefully whatever impact there is, is limited)

Two interesting things I noticed with the MPGuino. One, the speed can jump around by as much as 2 mph (though usually less). I'm guessing that, on average, it turns out as a good approximation of the actual speed? And two, when coasting at higher speeds while still in gear, the fuel use drops to 0. I'm a bit surprised, but hoping it is not just lack of signal sensitivity.

[Istas]

One I didn't even think of for an always-on power source... The horn!

The fuse for the horn is immediately above my left foot, so I just piggybacked a wire into the fuse slot for the horn and now it's all working correctly. Time for calibration.

I am excited.

[Istas]

Or, I am perplexed and aggravated.

I think my MPGuino is overheating. That little black square on the back of it is getting too hot to touch, and the device just went blank. It came back up after a few moments, but that heat worries me. I've disconnected it until I figure out, or learn, why this is happening.

I also got a radiator fan light hooked up, and it works perfectly.

[stevey_frac]

Originally Posted by Istas

And two, when coasting at higher speeds while still in gear, the fuel use drops to 0. I'm a bit surprised, but hoping it is not just lack of signal sensitivity.

This is called Deceleration Fuel Cut-Off, and is something that many cars do. its normal.