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General => The garage => Topic started by: Khare on 30 April 2012, 20:53
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Right, going to open a great big can of worms here. There's popcorn to your left and a glass of JD & coke on the right, chilled.
Are spoilers a pointless addon that barry and his boys like putting on their FWD Astra's or are they actually beneficial so long as they're placed in the correct position?
I ask because (Yes Glen, some Mk3's do oversteer :grin:) on several occasions my Mk3's rear has stepped out of line, both in wet and dry (but more often in the wet, obviously). It got me thinking about spoilers on FWD cars. Some may say they're a pointless addition on a FWD car and it's done purely for cosmetic purposes, and to a certain extent I agree. But if a wing was to be put in the correct position at the back of the car, sure it'll add downforce/reduce lift. Afterall the FWD BTCC cars ave rear spoilers and they're not just to look pretty.
Discuss.
PS: Obviously at 30mph the wing will do nothing, I'm talking about at track days/very spirited driving.
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Well my view is that has to help, I ran mine without the factory spoiler for a week once and you could notice the difference
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Indeed. Front searching the internet I've found two standout cases. One was of an integra being unstable under heavy braking and another was of a 1.1 106 that used to be tail happy and since having a spoiler fitted it's not oversteered since.
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Look at Audi with the early mk1 TTs.
They were completely unstable, and part of the recall to remedy this was to add a rear spoiler. Its got to have some sort of an effect.
That said there's going to be a difference between a OEM part thats had 1000s of hours spent on airflow and some crazy fast and furious setup.
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at the sort of speeds the aerodynamics come in to play, i wouldn't think it matters if its front, rear or 4 wheel drive.
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60mph that aerodynamics start to take effect isn't it?
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couldn't say, suppose its different for every car.
cant get my head around why you think it being fwd or rwd makes a difference?
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Because the general thought is it's used on rwd cars to help push the rear down for more traction.
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so by that theory as long as you're not creating so much downforce* at the rear as to lift the front driven wheels a spoiler will help the overall stability. a question of fine balance and intricate design though and not just some bolt on tat from halfords :grin:
*not the correct terminology i know, its late gimme a break
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so by that theory as long as you're not creating so much downforce at the rear as to lift the front driven wheels a spoiler will help the overall stability. a question of fine balance and intricate design though and not just some bolt on tat from halfords :grin:
We seem to have a few around here that think big spoilers look :cool: to me it looks like you have an ironing board stuck to the boot :grin:
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Ofcourse the spoiler has to be of the good quality and well developed type. Not just the halfords special one. From what I've read road cars have a balance of between 60/40 and 52/48, so adding downforce at the back will help balance the car.
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look at the fast stuff fwd rwd 4wd quite a lot of them have a spoiler of some sort.
aerodynamics has a massive effect on a car and how it behaves but the effect it has may not be the effect you first thought it would have withou very expensive modeling software or a wind tunnel its all guesswork and experimetaition.
with a mk2 if you decide to flat bottom it it has a mahoosive effect on front end grip and turn in but the back feels like it's gone light, the experiment as doen with mk2 gti and a few sheets of 9mm ply tek screwd to the underside after reading niges build thread the question is did it make the back go light or was tehre no change and just loads more grip at the frount.
likewise wings can do funny things on some cars i swear they bugger up existing areos and make the car worse
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I say it depends who driving for instance lift off or follow through?
I'm sure the downward forces would change just from how you drive?
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Because the general thought is it's used on rwd cars to help push the rear down for more traction.
previously.....
60mph that aerodynamics start to take effect isn't it?
hmmm you've answered your own question. Downforce is only created at speed, the more you go, the more you'll get. from that type of rear spoiler it won't be doing anything unless you're going fast, so pullin away it isn't. toe in toe out being the opposite to what fwd have at the front helps that.
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Rear downforce is required for the same reasons on a FWD as a RWD car. It has very little to do with aiding the driven wheels with traction but instead it's all about keeping a good balance of downforce across the whole of the chasis. A RWD car with too much rear wing will understeer as the front washes out, so will a FWD car with too much rear wing.
I found when I added the front splitter to the MX5 it increased stability at speed and reduced understeer in the wet. When I then added the rear wing it dialed the understeer back in to a degree but further increased the high speed stability so was a good trade off.
Aero is hugely complex but cool. GO watch racign cars with lots of aero drive in the wet and it's brilliant to see the spray being contorted by the wings and canards etc.
nick
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negative pressure and votices.
Go look them up.
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Yes, obviously it's going to create drag, is that what you're trying to say?
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not nessaseraly
drag is not all bad if the grip the aeros gives you makes you faster overall even tho it dents V-max all is still good.
traying the car or giveing it a smooth underside will actualy reduce drag and make it faster
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But without a diffuser and/or wings you're going to create lift aren't you?
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There is a very very noticable difference when I put my spoiler down at high speed. Cant say it feels any more twitchy, but there is a very noticable variation in drag, and wind noise. I actually never really noticed it until about 10 days ago, with the sh!te weather the wind really picked up on a trip down the dual carriageway. The Corrado isn't particularly aerodynamic, so I noticed it was being pushed all over the road. I put the spoiler down to combat it, and it really did make a difference.
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mk2 focus rs. front wheel drive lots of power yet they handle pretty good! they have a spoiler,
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I would say it does.
It won't help with straight light traction under acceleration. But it would probably help going through high speed bends to keep the back end in.
I agree with what Horney says.