Aftermarket underpanel on Honda Fit

[wdb]

I recently installed a Beatrush underpanel on my Honda Fit in an effort to improve fuel economy. It worked. Comparing 10 tankfuls before installation to 10 tankfuls after installation, my fuel economy increased by about 2MPG (38-ish before to 40-ish after).

The panel itself is made of aluminum and feels very sturdy. It has cooling vents cut into it to draw air out of the engine compartment. It is very nice looking and well made.

Installation is pretty straightforward, 6 bolts going into pre-existing holes. The mounting hardware is made for Japanese-spec vehicles so minor modifications are required to fit US cars. Also the installation instructions are in Japanese, but the illustrations make it pretty clear what needs to be done. (I can't comment further on the mounting hardware because I bought mine used and it came with no hardware, so I made up my own. My comments here are based on the installation instructions.)

Once installed, the panel is very easy to remove. Take out the 6 fasteners and it's out of your way. Probably takes less than 60 seconds.

Here is a link to the Kamispeed webpage that describes the part. I can't comment on Kamispeed as a vendor because I bought mine used from a private party. I don't know if anyone else in the US offers the part.

Below are some pictures of the Beatrush piece and my recommendations on how to install it.

First, the underpanel itself.


Here it is next to the factory undertray -- or more accurately the horizontal, under-car part of the undertray after I cut the vertical pieces off (more about that next). As you can see the Beatrush panel covers a lot more real estate.


I cut the vertical side pieces off the factory plastic piece and reinstalled them on my car. They finish off the insides of the wheel wells and prevent a lot of gunk from getting into the engine compartment. They're also very secure, connecting at 4 points; two at the top and one each at the front and back edges. I highly recommend doing this. Here are shots of the vertical pieces, driver's side then passenger side.




Finally, here is a picture of the Beatrush underpanel on the car. It covers the entire engine compartment all the way back to the front crossmember.

[Red]

Thats pretty cool that the aftermarket is starting to produce this stuff

[SVOboy]

That's pretty neat. You can always count on the japanese aftermarket to come up with some cool stuff. Do you know how it was marketed?

PS: Welcome to ecomodder! You're obviously off to a good start.

[NeilBlanchard]

Hiya,

I'll post the picture from the Kami Speed site, until you can post your own pictures.

Now, you'll have to try an upper grill block, etc., to get your FE up to at least 45mpg...

[MetroMPG]

Interesting product.

Any chance you're going to input a fuel log and/or post the specifics of those before/after tanks?

I'm wondering the same thing that SVOboy is: what's the marketing angle for this panel - aerodynamics & fuel economy? Bling? Off roading?

[cfg83]

wdb -

Wow, I like the rear-pointed venting.

CarloSW2

[trebuchet03]

Originally Posted by MetroMPG

I'm wondering the same thing that SVOboy is: what's the marketing angle for this panel - aerodynamics & fuel economy? Bling? Off roading?

Some company makes skid plates for VW - marketed to keep road debris away from the oil pan... Which, in some cases, has cracked when something hits it or when it hits the ground (because you've lowered your car, went too fast over a bump or whatnot).



I'd get it, but it's $275... Maybe one day I'll make my own...

[ChrstphrR]

The VW pans are made by Evolution Imports, off in B.C., Canada.

Oh, and they made one, a bit more pricy, with a little hexagonal plate that fits into a cutout for the oil drain. VW dealerships have a steel pan available, for the same purpose.

Specifically, the TDI engines sit lower to the ground than the gas engines, and they have a cast aluminum pan. Pressed steel pans dent. Cast pans crack, and then, leak, catastrophically.

I've been eyeing up their skidplate for a while, and I've bought a new MAF sensor for my Jetta off of them (WAY cheaper than the stealerships).

I keep making my own out of coroplast, but the last one the (already resting) raccoon road kill took it away

Heck, I lost my stock pan to a(n already resting) antelope on the highway the first drive with the car back home. Yeah, I'm unlucky. :P

--- veering back on topic ---

I bet the vents on the Honda Fit pan are meant for the radiator. When I re-covered where the stock plastic pan goes on my TDI with that coroplast tray, the water temperature was a good 10C or more higher.

And from Evolution's copy regarding their plate - they're marketing for engine protection. VW already stuffs a plastic pan underneath for most of the MkIV and MkV cars (1999-1/2 and newer) for noise, and aerodynamic improvements already.

A metal pan would have a few benefits above plastics

• If mounted securely, a metal sheet would improve torsional rigidity of your chassis (resistance to flex)
• Impact resistance from road debris
• A metal pan won't flutter (Stock VW plastic pans do, I've seen it on others driving down the freeways)

Of course... they'll cost more! ... I know trebuchet03's main objection is that thought in the back of his head that he could build one himself.

wdb, did your Fit have any trays or fairings stock? Glad your pan's working for you, too!

[trebuchet03]

Originally Posted by ChrstphrR

Of course... they'll cost more! ... I know trebuchet03's main objection is that thought in the back of his head that he could build one himself.

Aye Of course bigger, better and lighter An economist would probably say I've spent more time than it would have cost to buy


Another downside to the cast aluminum pan.... Steel drain bolt plugs on threaded aluminum... Stupid stupid stupid. Future designers and engineers, never do that - unless it's designed to come off very infrequently. If it must be aluminum, use an insert (helicoil, for example). Steel on Steel for fasteners that need to come off more than a few times.

[lunarhighway]

12€ worth of aluminum... it's thinner than the commertial available ones thincker aluminum would have cost me about 35€ as much but this grade could be bend by hand over a table edge and with angled edges it's quite sturdy. its thin enough to be cut with metal sheers
a few additional bracings and it slides underneath the edge of the bumper and bolts to the subframe...


just to say that a cheap diy alternative could perform identical to expensive aftermarket stuff...