What's the point of downforce on the road? HD 1080p
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- Опубліковано 28 вер 2024
- The internet reckons that there's no point in having downforce on the road. Here's what I think. Let me know what you think in the comments.
Thanks for watching!
DrP
Not watched this yet but last weekend at night I hit 125mph and my lotus Elise 220sport felt super light at the front. I’d imagine that the 250 would feel more planted at that speed.
Thanks, that totally backs up the point I made in the video. The Cup 250 generates more downforce @ 100mph (67kg) than the Exige Cup 430 (56kg) and yes does feel very stable at high speed which contrasts with how responsive it is at slower speeds. At 125mph the Elise Cup weighs 104kg more than a 220 Sport which is a lot in an Elise.
Well argued. Hadn’t thought about the benefits of adding weight w/can then come off at low speed.
Active weight management! Aero has come a long way since the rubber spoiler on the back of an XR3!
Lotus compared GT430 with and without wings (although wingless car still made quite decent downforce, something like 70kg at vmax vs 256kg), GT430 with wings was a second faster around Hethel. Wingless car was faster down the straights too. Engineer said you could feel the difference all the way around the lap and the aero car turned-in and stopped better.
Nicely put, I remember the literature on the Evora 400s talked about negative or no lift at 100mph which I didn’t fully get until I had my Evora S which notably went unnervingly light at (v.) high speeds.
Equally noticeable in my S2 Elise at lower high speeds
Thanks. I believe the factory claimed around 30kg of downforce from the Evora 400 at vmax, the Evora S was supposed to make half that so yes very little downforce at 100 mph but also minimal lift. Sport 410 with the carbon ducktail doubled the 400’s figure to around 60kg at vmax. The last GT410 Sports made a similar amount but were more aerodynamic at the same time making them highly aerodynamically efficient. Clever stuff, as you’d hope from the company that pioneered manny innovations in aerodynamics in F1!
Great video
Thanks! Glad you enjoyed it.
I follow your logic and argument, though I doubt that is the real reason these things are happening - its marketing above technical / engineering reasons, so your points are valid but most buyers are spending the money to have a car that looks faster and that means, these days, more like a track car, the brash shouty look.
Ferrari seem to be are strongly opposed to the more visually obvious stuck-on wings and are chasing downforce by more discreet means but they are definitely still interested in downforce. Even going back to the regular 458 Ferrari claimed 140kg of downforce at 120mph.
What's the point of downforce on the road? It's just to show off. At the speed we are allowed to drive, no force is generated enough to notice à difference. That s one of the reasons why most of hypercars/track oriented extreme cars are just undrivable at slow speed (Ex: Radical).
As in the video, the benefit is high speed stability not the increased grip that is the intention of aero racing cars. You don’t need massive downforce to make a car stable at motorway speeds but you need a lot to increase cornering grip. Elise Cup 260 gains over 80kg at 100mph. I could definitely notice the extra 100kg last time I came back from B&Q and that was in a 2 ton SUV!
@@DrPittenstein sorry but I don t think you drive at 100 mph on country roads... and on the highway I don t see the point to have a stable car at 120 mph.
@@PaddyMcQueen a car with downforce is more stable at 70mph too. It only takes one drive in a car that’s unstable at high speed to appreciate the value of high speed stability. You can get that from a heavy kerbweight too but you are stuck with that weight when you get off the highway and it’s not what you want in a sports car is it? So best of both worlds is an agile, lightweight sports car which gains weight and stability at speed.
Did you watch it? He answers this.
A bit of wishful thinking here i think personally. Yes it does make a difference, but not much at all. For example, you have comments here saying that a 220 Sport feels "Very light" compared to your 250 Cup which feels "Very stable" at the same speed. If the Cup really is producing 67kg at 100mph which i doubt, that's going to be around 40kg over the front wheels at 125mph. Barely half a passengers difference. I've recently heard that Lotus's DF number claims are very optimistic anyway, and how often are we all hitting 125mph on the road? I'd heard the UK was very strict on speeding these days, but at 140kph you're into licence losing territory here in NZ, so the only time I've (accidentally, your honour) reached a speed where either my Elise or Exige is producing any actual downforce has been for a split second, and also in a straight line. On the track of course would be different, but if I was doing serious track work in the Exige the 40-50kg of downforce it supposedly produces at around 100mph would be hardly worth having, and you'd want to modify the car to produce much, much more to get real benefit. If you're really enjoying sustained benefits of downforce from a factory Lotus on the road, you're going to lose your licence pretty soon I would wager. But on the other hand, wings and spoilers look cool, and any amount of stability is better than lift, even if it's almost negligible ;)
How are you finding the 250 cup btw? Which do you find yourself taking out more frequently for a Sunday morning drive, the Elise or Evora?
as it happens Lotus revised a number of their downforce gains some time around 2019, some were revised down such as the Exige Cup 430 (220kg to 171kg at vmax) a few were revised up slightly so the figures I'm using are more accurate I believe. The net gain is bigger than 67kg of downforce at 100mph if you're comparing to a car that generates lift. There are a few corners at tracks in the UK which are easy flat in an Elise Cup at 120+mph and Evora GT430 at 130+mph. The same corner in the Exige V6 Cup which made less downforce (42kg@100mph) needed brave pills to take flat, it could be done but you had to turn-in at exactly the right place or things could get pretty scary, pretty quick. The difference is night and day so the downforce is very real in my experience and as per the video the benefit at legal motorway speeds is stability.
Good question Elise or Evora, one I ask myself regularly and it's rarely an easy or obvious choice but nice first world problem to have. Planning to do a video on that actually so watch this space. Cheers!
its to prove you really are a boy racer
One of the guys I do club days with in Aus happens to be the quickest Elise driver in our club at Phillip Island, one of our quickest tracks.
.He thinks that my large wing is slowing me down too much on the fast straights. He uses no rear wing and is quicker than me through the high speed corners. He thinks that I should just trust the mechanical grip of the Lotus chassis and lose the wing. We have similar horsepower.
I’d love to hear your opinion. It would also be amazing to do a video on track with and without a rear wing.
Thanks for the fab content
Thanks, I’d love to do a track comparison with and without wings. Lotus claimed the aero parts on the Evora GT430 were worth 1s around the factory test track. The GT430 Sport (the one without wings) was 10kg lighter and was faster on the straights.
But how much stability through downforce does one really need?
Is 992 GT3 noticeably less stable than 992 RS (which has 3 times as much DF) in public road use?
And does that make 992 GT3 Touring an unstable car?
Funny how 997.1 RS is often rated as the superior driving experience compared to newer GT products with just 55 kg of downforce at 300 kph.
Yes GT3 Touring would be noticeably less stable at high speed than a GT3RS. Dramatically so at Autobahn speeds where the downforce on the 992RS would make it the slowest in terms of top speed of all the GT3s. But compared to older 911s the 992 GT3 Touring benefits from many improvements in aerodynamics. Plenty prefer the air cooled 911s as a driving experience and that is despite having treacherous on-limit handling and awful chassis balance. For every Porsche since the 996 GT3 there is always someone claiming theirs was the best.
Manufacturers are adding downforce for the same reason they are adding power and talking about 0-60 times and Nurburgring lap times. It sells cars. It has nothing at all to do with the driving experience on public roads , and has everything to do with benchmark racing and for one guy to brag to his friends about. Showing a video of breaking the speed limits on public roads doesn't actually prove your point.
Your point about "not generating lift" is important though. Gordon Murray has a bit to say about removing lift without extra weight or aero loss (wings, etc).
My point was that cars with genuine aero may look like track cars but they are often surprisingly comfortable and composed at legal motorway speeds because they become more stable. Most cars get lighter at higher speeds, so the delta in driving experience between an ordinary car and one that gets heavier at speed is more noticeable than you might think given what is often a modest sounding downforce claim. In what way is this a video 'of breaking the speed limits on public roads'?
Another great video Jonny
Thanks Sam, our last collaboration is still by far the best on the channel, I don’t think I’ll ever top that without your skills! Have to say the drone work still really stands up. Thanks again.