Technical Jeremy Clarkson said something intelligent? Wheel Arches.

[Smiler121]

In the 1st episode of the new Top Gear series on Sunday when talking about the Ferrari He mentioned that the 430 Scuderia has slats in the wheel arches to improve airflow as cars tend to have pressure increase in that area.

I guess this causes drag?

I know the odds of my going so fast I'll notice the effect of air pressure in my wheel wells are low, BUT if it improved fuel consumption by a tiny amount or stability on the motorway I wonder how easy it would be to do?

Only really thinking about this as my rear bumper is badly scratched in what I'm guessing would be the right kinda places anyway.

 

[balidey]

In theory, any aerodynamic assistance will reduce fuel usage, but you will NOT notice any difference at the pump.

Do it by all means for looks, but don't expect any savings.

I remember an article about (I think) an integrale a few years ago. the quote was something like 'its got the aerodynamics of a brick, and if you smooth off the corners, you still only have an aerodynamic brick'

 

[balidey]

Some ways to save fuel.....

Put duct tape over all body panel gaps (bonnet, doors, boot)
Make sure tyre pressures are spot on.
Make sure tracking is correct.
Don't carry un-necessary load in the boot
Drive sensibly (what? in a cinq? Never)
Fit low rolling resistance tyres (not sure they're available at our size)

Tail-gate. Yes, thats right, reducing the gap to the car infront of you have huge affect on your fuel economy, much more that the rear 'slats' would.

 

[Smiler121]

I get all of the above & fully understand the fact that I drive everywhere @ relatively high rpm & accelerate heavily far too often makes the most difference. I have no plans to tape over my car, or use crappy tyres.

BUT I was thinking along the lines more of "how do I do this" & where would be most appropriate on a Sei, than I think this may be cool & however minor actually justified - now rubbish the idea!!!

Suppose I shouldn't have mentioned fuel economy :bang:

Admittedly I should have just said "how do I do this" - given the ever rising fuel costs, things that reduce consumption by the most miniscule amounts add up over a year - anyone want to move the thread to the styling section to save the topic becoming a "how pointless" debate?

I'm just doing fiddly little things to keep myself occupied over summer 'til I consider an engine swap in the winter. I guess that it would help wind resistance @ top speed more so - even if again only by a few meters an hour!!!

Given that I'd like to keep the car for as long as I can, I'm sure if it only cost a few quid, a bit of thinking & a fiddle to do it may even pay for itself over the next 70K miles, although I'm sure a wind tunnel would be needed to test benefits - Unlikely!!! :devil:

Oh Balidey, I've never noticed "umop apisdn" before - how cool!!!

 

[balidey]

as i said, go ahead and do it, as a styling exercise.

Infact to help you, I'll loan you my 430 Scuderia for a weekend and you can take moulds off the rear arches, OK?

 

[Smiler121]

as i said, go ahead and do it, as a styling exercise.

Infact to help you, I'll loan you my 430 Scuderia for a weekend and you can take moulds off the rear arches, OK?

Tell you what - I'll borrow the Scuderia, & honestly all I'll do is spend time covering the back end in putty

Does a moderator fancy moving this over to styling, or should I link to it - may yield somebody with an idea of the best way to do it.

Although I was hoping for some kinda' suggestion from the Teccy end of things. I wonder if the impact of installing them is only relavent @ real high speeds well over normal motorway/fast country road speeds, or if people have a best suggestion as to where in the arch it would be worth doing.

A stock Punto Sporting that parks somewhere near me has what look like fake? wheel arch vents as standard styling effect from what I recall (never looked properly up close).

I'm not naive enough to think that I'm gonna' feel a benefit - though I really would love to know what, in real terms this kind of thing would do - look @ the cars coming out with things like active intake vents that seal off when cooling isn't a major issue in order to reduce drag for example.

Maybe I could call it the "Seicento Bluemotion"? :idea:

Lets face it if I plan to keep my "brick", fit a new engine for the hell of it & spend forever & a day polishing it up all shiny, I might as well round off the edges while I'm tailgating everywhere after my mates tape my doors over!!! :slayer:

 

[randomizered]

Unless you can hire a wind tunnel (pop over to mira you will never know the benefits even if you do generate them

Not worth it tbh....don't listen to that clarkson man

Kristian

 

[balidey]

Unless you can hire a wind tunnel (pop over to mira you will never know the benefits even if you do generate them

How do you think I came to the conclusions of my post? Yes, thats right, we hired MIRA.

 

[fingers99]

Strange how the stuff that was run of the mill in TransAm about 35 years ago is now coming back. Not just the Ferrari, but the RX8.........

You'd expect it to have had an effect then, after all, Porsche, McLaren, Penske et al are not exactly dimwits.

But I'd guess that any benefits were relatively minor.

If the Integrale is a brick, does that make the Cinq a briquette?

 

[balidey]

If the Integrale is a brick, does that make the Cinq a briquette?

 

[SuicideUK]

Or the seicento a curvy brick lol?

Luke.

 

[Advanced Driver]

Tail-gate. Yes, thats right, reducing the gap to the car infront of you have huge affect on your fuel economy, much more that the rear 'slats' would.

NO! Tailgating is the worst thing you can do. Apart from the fact that it is dangerous, you are more likely to save fuel by increasing a bigger gap. By leaving a lager gap (at least 2 seconds in good conditions) you have time to react to everything slowly. If you tailgate you need to slam the brakes on everytime the person in front brakes. If you have a good gap then you just lift of the gas a bit (or in some cases you may not need to do anything), and you don't need to take off as much speed. So leaving a larger gap will save fuel.

 

[ronnieronson]

NO! Tailgating is the worst thing you can do. Apart from the fact that it is dangerous, you are more likely to save fuel by increasing a bigger gap. By leaving a lager gap (at least 2 seconds in good conditions) you have time to react to everything slowly. If you tailgate you need to slam the brakes on everytime the person in front brakes. If you have a good gap then you just lift of the gas a bit (or in some cases you may not need to do anything), and you don't need to take off as much speed. So leaving a larger gap will save fuel.

very sensible advice - but I think it was in reference to the effect on drag.
If you are travelling close enough in someones wake, they effectively cut a groove through the air - which lessens the wind resistance on your vehicle.

 

[RuiG]

Just take Nascar for an example... driving on the cone (as we say here in Portugal) reduces fuel usage and saves horsepower for overtaking... but it also has a downside... engine will heat-up much faster. Example: people over here like to go to topspeed racing to VDG (a 17km straight road on a bridge) and they use slipstreaming a lot. There's some stories about Civic Type Rs overheating because they were too long behind a car. F1 cars have the same problem and it's not unusual to see the driver move from behind to let the car breath and cool down.

 

[nmrmak]

i wouldn't believe that, wouldn't their radiator fans turn on? Well, could be possible on a heavily tuned car zooming at max revs though

 

[Smiler121]

i wouldn't believe that, wouldn't their radiator fans turn on? Well, could be possible on a heavily tuned car zooming at max revs though

The big thing with a fan under the bonnet is that it will not provide anywhere near the cooling effect in stationary or low pressure air that normal free airflow through the engine bay + over the rad achieves, hence big fans used on rolling roads.

Interestingly on the later Seicentos they added vents in the front of the front wheel arches, I wonder if this was to change pressure build up under the bonnet, maybe to allow better cooling flow, or to encourage brake cooling in the arches?

<EDIT> I took a look & it is only the drivers side - guess this might improve airflow over that side of the bay & therefore keep the rad cooler?