Factory fitted belly pans pics

[Eddles]

I'm posting pictures of my ECO4's factory fitted belly pans which were fitted to improve FE only just in case a few of you would be interested in seeing how a car company would shape/fit it. I really hope these will be useful for you! For more pictures, or more specific ones, just let me know and I'll be happy to take them. It's interesting to see that the engine cover has holes in it, I guess to allow some air in for cooling.

Pic 1 - the engine cover
Pic 2 - Another view of the engine cover
Pic 3 - The back of the engine cover. Bit hard to see here, sorry.
Pic 4 - Rear pan - I think to cover the fuel tank
Pic 5 - Back view of the rear pan. Not a lot to see.

[daqcivic]

Thanks Eddles, good pics. I am always wondering what underbody aero mods the factory guys are focusing on (since they have wind tunnels and such) vs. what we amateurs are coming up with.

Your ECO4 and cars like the Civic Hybrid seem to get noticeable improvements targeting specific areas despite leaving some other areas alone (like exhaust tunnels and wheel wells relatively exposed). Of course what makes a difference all depends on the specific vehicle's shape and its major sources of drag, and to know that you need CFG and controlled experiments, so we might as well mod everything that seems like it has a reasonable chance of improving aero.

[vtec-e]

Nice pics. On pic 2, what's that intake horn for? It's the one up towards the left of the pic.

ollie

ps: can i post pics of my own factory belly pan here?

pps: nicely inflated tires too!

[cfg83]

Eddles -

Thanks. I like the engine cover "dual intake" detail. The next time the car is up in the air in the shop, it would be cool to get another set of pix.

vtec-e -

I thought the "intake horn" was a "just a horn", but I don't know.

CarloSW2

[Piwoslaw]

Originally Posted by Eddles

It's interesting to see that the engine cover has holes in it, I guess to allow some air in for cooling.

My car's engine cover also has holes in the front. Covering them was my first ecomod

[Eddles]

daqcivic - yeah quite, they know what to do. However, a full cover on the underbody would be the best, but they do have to sell cars and limit their imaginations... As you can see in the final pic, the back of the car is very dirty (aerodynamically) especially with the rear bumper, that area probably will benefit a lot with a cover-up but not sure if I have the time/experience to do it.

vtec-e - I think that's the horn. I'll have a look later. Of course you can post your pics - it's a free country Nicely inflated tires? How did you know?

cfg83 - yeah I plan to do so. I need new tires soon, so hopefully the tire guys will lift up the car properly rather than using jacks, but I'm not holding my breath.

[lunarhighway]

thanks ! those pics where just what i was looking for! i've just come back from to store with some aluminum sheets to make a new version of my undertray that covers everything up to the front firewall.

those air inlets seem like a good idea to replicate!

i wonder what your cars Cd is, the standard astra G is said to have a respecable 0.29Cd so these pannels should nock quite a bit of it!

And if you considder that the opel calibra 8valve verions had a 0.26 Cd with the aid of underbody pannels and a top grillblock, but the 16v versions where only 0.29 without these features
(the same as my vectra A/cavalier mk3 on wich the calibra was based and wich also infuenced the astra G)
than perhaps it's not to crazy to think that these cars with some underbody treatment and a grillblock might have a Cd that approaches that of the calibra!

[vtec-e]

Originally Posted by Eddles

vtec-e - I think that's the horn. I'll have a look later. Of course you can post your pics - it's a free country Nicely inflated tires? How did you know?

I re-checked the pic and yes i guess it is your horn. Silly me!
How did i know your tires are nicely inflated? The contact patch looks small from the side. No drop in grip though eh?!?

ollie

[Eddles]

lunarhighway - Astra has 0.29Cd, that's not bad - explains why the car is rated at 80 MPGuk on highways... wouldn't be surprised if my car has a Cd of 0.26.

vtec-e - So inflating it high = less grip then? I've been told inflating it high = no change in grip. That's probably why the car's a little skittish around corners... Yes it's definitely the horn, btw.

[vtec-e]

Sorry, i was a bit vague; kids hanging out of me! You're right about the grip. There is no loss in grip at higher pressures. Anyone i come across that says otherwise gets told to prove it!! Having said that, one tire installer i met said that the wheel would bounce because the shock absorber is only able to react at a certain speed. A softer tire would (supposedly) allow for this. I have felt my car behaving "skittishly" across the odd turn where there was a rough surface but it is only at slow speeds, around 10 to 20 mph, and never during braking. No matter how hard i brake. I'm a little unsure of this though and would like complete and concrete proof on the subject. But i fear it's a bit like the holy grail.
BTW, sorry to go on so much about the horn, but isn't it a funny place to have one? Wouldn't it fill up with mud and water? The sound would travel well though.

Anyway, back on topic. That rear pan is very smooth. Is it common across the range or just the eco model?
The front pan is smooth too and has inlets under it. My yaris has outlets on it, facing the other way. I'll post a pic to show what i mean. That is strange. Something to ponder over a few cool ones.....

ollie