Full under body panel for 10% fuel efficiency gain. (about 20% aero drag reduction)

[scitzz]

^^ Google it. Wikipedia.

Well, I know that Naca ducts are used for cooling, and I thought usually for cooling brakes.

[TominMO]

^^ Google it. Wikipedia.

[scitzz]

2 things:

1) NACA ducts.... 'nuff said

2) have you noticed a reduction in cabin noise since the inclusion of the full pan?

Pardon my density, Naca ducts to cool, the Cat?

[Movin]

I must have missed something..( not unusual for me ) In racing I understand the need for ducting air to prevent overheating, but for this project if heat is some where is it not the first priority to eliminate the lost energy creating the excess heat?

[mikeyjd]

At John's suggestion, I blocked off most of my grill and all of my bumper openings, and put a small air dam under the bumper. The Festy definitely got quieter at hwy speeds. Working on this for my Aspire now too.

Definitely way quieter at highway speeds. Ill look into naca ducts.

[TominMO]

2 things:

1) NACA ducts.... 'nuff said

2) have you noticed a reduction in cabin noise since the inclusion of the full pan?

At John's suggestion, I blocked off most of my grill and all of my bumper openings, and put a small air dam under the bumper. The Festy definitely got quieter at hwy speeds. Working on this for my Aspire now too.

[jawbraeka]

2 things:

1) NACA ducts.... 'nuff said

2) have you noticed a reduction in cabin noise since the inclusion of the full pan?

i 2nd both these questions too..

if you do happen to get a prototype up and working properly, send us a template or design for the template and i'll get a local fabber to whip something up.. sounds very promising all the same.

[Festevil3]

Interesting ideas, hope it works out for you. Start a excel spreadsheet with data, I would be interested in your results

[FestYboy]

2 things:

1) NACA ducts.... 'nuff said

2) have you noticed a reduction in cabin noise since the inclusion of the full pan?

[mikeyjd]

best thing to do , hit up a wrecker and get them to cut the ass out of a festiva, or if you have a spare, cut it yourself.

then from there, mould the bottom with a heat sensitive plastic that will "mould" but turn rigid, then from there design the underbelly yourself.. it wouldn't be hard and TBH if it does all that it says it will, you may be looking at a potential client for one of these in the future.

also, must be plug'n'play with current chassis so irregardless of what happens with bodykits, it won't interfere with the overall operation of new underbelly.

can't wait to see the next chapter of this and overall version upgrades of this impressive upgrade..

the other thing i was thinking, was if it were "track" tested, then you'd be able to get really impressive results on overall speed and time trail data as well as fuel efficiency results and so forth... but only if you wanted to carry the project that far.

I hadn't thought of producing it for anyone else.. but it would be cool. The issue would come down to money, I think. It would improve aero on the track and help drastically with high end speeds. The issue would be coming up with the money to manufacture for such a small niche, and getting the niche to actually pony up like $300-400 (a wild guess) for something they don't need per say. It would be a fun project, but would likely be better suited for someone that already owned a tool&die shop or something of like nature.

[jawbraeka]

i'll look into it. It seems to be working well so far as is, but I will revisit this if I run into any problems this summer. Thanks for the pics, they could also aid in my boat tail design.

best thing to do , hit up a wrecker and get them to cut the ass out of a festiva, or if you have a spare, cut it yourself.

then from there, mould the bottom with a heat sensitive plastic that will "mould" but turn rigid, then from there design the underbelly yourself.. it wouldn't be hard and TBH if it does all that it says it will, you may be looking at a potential client for one of these in the future.

also, must be plug'n'play with current chassis so irregardless of what happens with bodykits, it won't interfere with the overall operation of new underbelly.

can't wait to see the next chapter of this and overall version upgrades of this impressive upgrade..

the other thing i was thinking, was if it were "track" tested, then you'd be able to get really impressive results on overall speed and time trail data as well as fuel efficiency results and so forth... but only if you wanted to carry the project that far.

[mikeyjd]

this is exactly what i was talking about..might be better if it were shaped from the one piece of material, but excellent prototype none the less. just need a aerodynamic bodykit and you're set.

i had a few ideas about this in regards to the heating and airflow

wrap the exhaust in heat shield like what is done for exhaust header to reduce heat escaping, then have a "boxed channel" around the exhaust to allow for airflow down to the rear of the car where an "exit" is available to allow the airflow to suck the hot air out..

at the front of the car, have a narrow gap between the car and the undercar plate of maybe 2" and funnel the air into the formentioned channel to allow the airflow down the channel. also have an opening for the engine bay to allow air to be pulled through to the back of the car also, and two vents on the bonnet to allow air to be "sucked" into the bay and i think you guys can see where i'm going.

here is a picture to help you "plan and refine your design"


i'd also do a bit of research into the ferrari's and lamborghini's that use this design as a standard feature..

it'd be cool to see this implemented into the festiva.

i'll look into it. It seems to be working well so far as is, but I will revisit this if I run into any problems this summer. Thanks for the pics, they could also aid in my boat tail design.

[mikeyjd]

this is exactly what i was talking about..might be better if it were shaped from the one piece of material, but excellent prototype none the less. just need a aerodynamic bodykit and you're set.

I like it in more than one piece for the sake of maintenance, but 2 pieces would be better than the 3 mine is. Fiberglass or carbon fiber or some sort of oem abs pan would be awesome. Unfortunately no one makes em, and I probably couldn't afford them if they did . And I would love a custom aero festy lol. Who wants to build me one?

[mikeyjd]

Where did you find the large sheets of Coroplast?

http://www.piedmontplastics.com/

Awesome! I've always wanted to do this

you should.

I hope you can figure out a way to keep good records so as to compare before and after. Great idea.
You might chuckle about this but dimples on golf balls create a boundary air layer that allows for more efficient travel. I wonder if thoroughly working a Festy over with a ball peen hammer would make it more fuel efficient.

I've kept records. It's impossible to to calculate with 100% certainty as I have done other mods in conjunction. This belly is a month old and has worked quite well thus far. My estimates for affectives (in the post title) are based on anecdotal observations and projections as well as other under belly pans on ecomodder.com.

How close is that to touching your exhaust? Your not worried about it melting through are you?

4 inches of white (not pink) fiberglass insulation has held up thus far. It is ever so slightly warped where the catalytic converter is, so I'm contemplating integrating a steel mesh insert 18''x12'' or so.

i've thought about this also. not the full belly pan but judiciously placed small foils/covers over or in front of suspension components in the airstream. potential problems i'd think about with the full pan treatment: engine cooling. where does the air entering the radiator now exit? becoming airborn. the right speed, the low weight, the gust of wind. you've surely seen a news clip of a hydroplane boat flipping?

engine cooling hasn't been an issue even during long trips in 85+ weather thus far. the air entering the radiator still has plenty of places to exit (hood cowl, wheel wells, it's rigid but it's not tight to the oil pan either)

Nice. Yes, before and after numbers anxiously awaiting.

before all mods baseline mpg = 48.8mpg
since mods = 62.65 (including better driving although the baseline tank did include some hypermiling)

My biggest concern (because I have so much rus- err - weight reduction) is that it would hold in excess moisture, thus leading to extra weight reduction.

I suppose if you triple-sprayed it before putting this belly on, it might not matter as much.

-Joe

I've taken this off a couple times after rain to check for moisture issues. So far so good.

There's no way this will work. The increased drag of the attached jackstands on the ground will more than compensate for the lower drag of the belly pan.

Sometimes style is more important ^

[jawbraeka]

this is exactly what i was talking about..might be better if it were shaped from the one piece of material, but excellent prototype none the less. just need a aerodynamic bodykit and you're set.

i had a few ideas about this in regards to the heating and airflow

wrap the exhaust in heat shield like what is done for exhaust header to reduce heat escaping, then have a "boxed channel" around the exhaust to allow for airflow down to the rear of the car where an "exit" is available to allow the airflow to suck the hot air out..

at the front of the car, have a narrow gap between the car and the undercar plate of maybe 2" and funnel the air into the formentioned channel to allow the airflow down the channel. also have an opening for the engine bay to allow air to be pulled through to the back of the car also, and two vents on the bonnet to allow air to be "sucked" into the bay and i think you guys can see where i'm going.

here is a picture to help you "plan and refine your design"


i'd also do a bit of research into the ferrari's and lamborghini's that use this design as a standard feature..

it'd be cool to see this implemented into the festiva.