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Never really hear much (if any) talk about downforce on this forum.

Does anyone else have problems driving on the highway in high wind / wet conditions.

Ive never had any problems in other cars (apart from a van).
Just the mx5 seems to squirm around and in the wet, it becomes scary over 90kmh.

So ive narrowed it down to two things: Poor wheel alignment & lack of downforce in such a light car.


Do you think the addition of a rear wing & front spoiler will help? If so how effective is the stock wing (it doesnt look very). What can i add to the front?


Cheers

Eric

most convetibles will feel 'floaty' at high speeds due to poor aerodynamics obviously. especially a car as light as the mx5...

if its really bad though...check wheel alignment, buckled rims, wheel balance and any bent suspension components.

I wouldnt say the MX5 has bad aerodynamics (except with the roof down), they're almost like a bullet, being so much smaller and lower they have considerably less frontal area to create drag.
The lower the car and addition of front spolier etc can cause more air to pass around and over the car sucking it down to the road better at higher speeds.
But i do agree with ducktape though, due to being so light they do float around abit and are affected alot more by road undulations.

but the fun factor still outways this!

Edit: Sorry i for got to say, i dont believe the stock spoilers and wings would do anything useful for downforce, unfortunately i think the only useful downforce from wings u can get is from proper inverted aerofoil wings mounted higher off the boot.

Tyres and alignment. My car is stable as a rock.

I must admit that over 160km/h (on a track, of course) that my SP does tend to get a bit light and floaty, but below that speed, it feels well connected ot the road.
I've thought about putting spoilers on the car to eleviate the problem, but I just hate the look of spoilers on a car.

tyres, tyres & tyres kitkat

AJ wrote:tyres, tyres & tyres kitkat

Aint the tyres, they are great in the wet!!!

Will try a wheel alignment when i get some new tyres in a couple weeks.

I think I read on a UK MX5 website that the front factory lip spoiler helps with this as it is actually an airdam forcing the front down.

Ben

kitkat wrote:

AJ wrote:tyres, tyres & tyres kitkat

Aint the tyres, they are great in the wet!!!

Will try a wheel alignment when i get some new tyres in a couple weeks.

it's squirming at 90 kmh in the wet, yet the tyres are great in the wet???


a cosmetic piece of plastic stuck on the front won't help that matey

AJ wrote:it's squirming at 90 kmh in the wet, yet the tyres are great in the wet???

plenty of grip in the wet!!!

Driving in the wet is fine until i hit the highway on a windy day. The car even squirms in the dry when its really windy...


Ill see what a wheel alignment does, if it does nothing ill look into a decent rear wing with a proper lip on the back spoiler... just have to find something that looks stock or somewhow modify a stock spoiler.

My bmw is planted in the wet, same tyres, 200kg heavier but has both front and rear spoiler. The front spoiler prob doesnt do much but the rear most definetly does. That car hasnt had a wheel alignment since i bought it also.

take some of that ridiculous rear camber out might help too

My standard vehicle has no problems up to around 120 (I try not to make any mistakes and exceed this if I can). I used to find my old MG used to get 'light' above this figure (as you might expect) but no such feelings in the MX-5..there again I'm not using it on a track....

I do find sitting in the silly seat of an RX-2 at 170 on the dirt (on a special stage) gets my spine tingling though.....

i havent sat in any mx5 that feels 'planted' over 120(maybe the NC's may be different?)...

our cars DO have really bad aerodynamics with or without roof on unfortunately...but i guess that all goes out the window when u can see the stars when ur driving gotta love topless driving

Mine feels OK. How old are your shocks?

JUles

jules wrote:Mine feels OK. How old are your shocks?

JUles

I wouldnt be suprised if they were past their expiry date.

The car feels great when its dry, 120kmh sweepers feels fine.

Its just as soon as i hit the highway on a windy day, even worse when its wet + windy. The car just seems to get pushed around by all the wind.

Hopefully a wheel alignment will help out though i highly doubt it.

Thanks for the feedback guys