Aquaplaning

[richard grigsby]

Had a heart-in-the-mouth moment yesterday on a wet M3 when I hit a smooth section of road covered with water - maybe 10mm deep - doing 70. Car lifted off and slewed sidways a few degrees. Fortunately the waterlogged section was only 50m or so long and I wasn't too out of shappe when I came out of the other side. Spent the next few miles sat in the middle lane doing 50...
In brief, all my tyres are legal depth - one of the rears will need replacing soon but the fronts are both good depth. Both front and back are 15mm wider than standard width.
Do NSXs aquaplane?
What tyres are best for water clearing and all year round performace in the UK?
Any tips most welcome. My budget is flexible as the cost of a more expensive set of tyres (if best option) probably wouldn't come close to repairing the damage from carouselling down the armco...
Richard

[Lankstarr]

Richard,

Sounds like a nasty experience; one that Matt has experienced with a new set of tyres also.

Matt didn't have front and rear tyres matched when his car aquaplaned and since changing to Goodyear Eagle F1's all round has not experienced anything similar. I'm running F1's and hit water all the time, no slidey slidey for me!

What tyres are you running?

Goodyears are a bit thin on the ground at the moment, Simon has been running bridgestones for a while now but is too much of a pansy to drive it in the wet;) he may be able to advise of their capability over water.

Cheers

Luke

[dan the man]

Im always aware of bad water on a motorway, when that ass gets a swing on at a certain point it aint coming back. Ive ben playign last few weeks on a knocked down supermarkets floor.

YES TILES :)

full of water she slides so easily... but at certain points its just so hard to get back..never mind at 70

[Kevin]

This has come up from time to time over the years.

Tyres need 4mm minimum of tread for wet weather driving. Somebody once was on a motorways and the car just decided to spin 360deg on its own accord. Others have complained of a 'squirmy' feeling from the rear, nothing to do with any curries the night before either.

It's never been figured out what causes this. One theory is the large toe settings on the tyres, causes variations when driving over different surfaces.

[Senninha]

Hi Richard,

I'm also running onthe F1's all round, on 17's, and have good all round performance. However, they will 'squirm' at the front if you hit standing water to fast :)

Performance of these tyres actually improves with mileage until you're down to 3mm. IMO it then drops away quick and is time for new rubber.

Good to hear you came out the other side unscathed!

regards, Paul

[cas]

Hi

sorry to hear about your experiences on the M3. I would have thought that the real reason is the light weight front, that is, in an aluminium car there is less weight pressing on the tyres to force the water out from underneath? If this is the case slowing down is the only thing that will help. If you have ever driven a VW beetle in the wet.....

[Senninha]

... I would have thought that the real reason is the light weight front.......If this is the case slowing down is the only thing that will help. If you have ever driven a VW beetle in the wet.....
... or a Lotus Elise if you want your eyes right out on stalks :eek::eek: and it doesn't need to be that deep either!!

[AR]

Guys even my Amazons aquaplane. Valid point about thread depth, I once had an interesting experience going through Caerphilly Mountain where the conditions turned from cold night to blustery.

Take care and get some new tyres when you can.

Cheers,

AR

[richard grigsby]

Thanks very much to you all for your help. I will go for the Goodyears all round as I have Toyos on the front and Eagle F1s on the back. Rear tread is down to 3mm I'd say so I am on the hunt now for new tyres!
The NSX Prime site also rates the Goodyears for performance and wear capabilities.
I didn't think too much about the incident(s) - it happened again a mile or so later - but having slept on it I realise what a mess it could have been for everybody if I had spun.
Now, where's that 'new underpants' shop?

Richard

Ps. I will have two 225 45 ZR16s for sale very soon. New owner can collect from me near Bath or I can courier. Details to follow.

[TheQuietOne]

You'll be very happy with the F1's all round even hitting deep standing water at 70 as I have done unintentionally a couple of time I have zero aquaplaning with the Goodyears....

[richard grigsby]

OK, thanks. I've just come off the phone to my tyre fitter and he says that, for the front, only 215 40 16s are available in GYs and not the standard 45% profile.

Can you let me know what you have fitted please?

[Martin]

I don't do much wet weather driving, but nevertheless, I still want Goodyear F1's anyway. I've tried to get hold of them for a standard 16/17 combo, but to no avail. Can anyone help me and tell me where I can buy them?

Cheers
Martin

[goldnsx]

I went with 205/45/16 GS-F1 in the front this summer and will change to 245/40/17 (from 255/40) this winter in the rear. My 91 TCS should be fine.

[TheSebringOne]

Whatever tyres you have, aqua-planing is a problem due to the unique set up of the car & lightness at the front especially (weight 42% front & 58% rear?). Some tyres are better than others. Alot of owners here vouched for the GY F1 GSD3s being the best due to its unique aqua grooves and the way it disperses water. I have'nt had these fitted yet, but I would be happy fitting them.

If water is a certain depth and continous over a certain length, aqua-planing is unavoidable anyway. I'm on a look out for rear boots soon, but since only use the car when its dry like Simon, Im going down the BS route for ultimate dry weather grip, rather than ultimate wet weather grip in the GY. Tyres to me are either Summer or all year round, so it depends on when you drive your car the most! If I get caught out by a torrential downpour, I would not let the VTEC kick in on any tyre, but would feel safest with GY. HTH :)

[dan the man]

James VTEC aint needed to kick the rear out when wet, peak torque is way before vtec and can unstick easily when weighted turning up a sliproad :)

As for wet weather i just slow the f*ck down on motorways :(

[reg]

Aquaplaning.

From what I have learnt and been told.

No power, I found with the NSX trailing throttle upset it less than what I have now. Firm grip on the wheel, absolutely no brakes or turning input. Get the wipers on constant les to worry about.

Remember, its water not ice.

[richard grigsby]

I certainly had a firm grip on the wheel - dents have only just come out since yesterday morning!
I'm getting new GYs for the rear tomorrow - standard 245 width.
The available GYs for the front are only 40% ratio so I'm keeping the Toyos for the time being. Does anyone know the implications of fitting 40s instead of 45s - apart from the 10/11mm difference making them spin faster - is there anything else to consider?
Richard

[richard grigsby]

Nothing is ever easy is it? Goodyear don't make a 215 40 16 tyre so I am now looking at changing the whole lot to Bridgestones REOs and getting all sizes back to standard.
For those who run GY all round - what do you put on the front please?
Richard

[TheSebringOne]

Dan, what I meant to say is that you need to be gentler on the throttle when theres deep standing surface water or in a torrential down pour. I feel safer if in addition to above, if I avoid the VTEC too. :)

Richard, all that going down a profile from 45 to 40 at fronts means the front sits a bit lower and the TCS won't be affected as below the 15% tolerance. HTH

[amo]

had a little wiggle on my backend when i had 265 lol did think ohh shiit lol
but now got 295
not had a prob yet lol
thx amo

[jaytip]

had a little wiggle on my backend when i had 265 lol did think ohh shiit lol
but now got 295
not had a prob yet lol
thx amo
I thought a wider tyre accentuated (sp?) the problem?

[dan the man]

maybe a wider tyre does 'float' more.. certainly on snow but maybe with more good tread sometimes it might help

[Nick Graves]

A wider tyre will accentuate the problem, as will letting the tyres get anywhere more than about 50% worn.

The tread pattern is also critical.

A good tread pattern for dry grip (as in the RE010s, S-02s etc) is generally not well-endowed with grooves for water displacement.

The S-02s on the S2000 (a lighter back end, with almost the same tread width as the NSX and therefore a reputation for reversing into hedges) had an extra wide footprint and few water sipes. It's been withdrawn and replaced by a more normal RE050a which is allegedly far better in the wet.

Winter NSXstormers may wish to think of doing likewise.

[NoelWatson]

James VTEC aint needed to kick the rear out when wet, peak torque is way before vtec and can unstick easily when weighted turning up a sliproad :)

As for wet weather i just slow the f*ck down on motorways :(

For some reason my car has peak torque past 6000 rpm according to dyno...

[Midnight Blue]

If I remember my basic theory correctly, aquaplaning speed is approx 9 times the square root of the tyre pressure. (Tyre pressure in PSI and the speed would be Knots. 1 knot is approx 1.16 mph).

That would be in the region of 50 -55 mph.

Below this speed the water cannot lift the tyre off the road. Better tread pattern will delay the onset of aquaplanning beyond this speed.

Regards,

Andy

[AR]

It was 0 degrees and I chicken out today. There was so much ice on the roads around my house, that I was glad I took a 4X4 and not the NSX out today!

[NoelWatson]

If I remember my basic theory correctly, aquaplaning speed is approx 9 times the square root of the tyre pressure. (Tyre pressure in PSI and the speed would be Knots. 1 knot is approx 1.16 mph).

That would be in the region of 50 -55 mph.

Below this speed the water cannot lift the tyre off the road. Better tread pattern will delay the onset of aquaplanning beyond this speed.

Regards,

Andy

I assume you mean pressure exerted by the tyre on the road and not pressure to which the tyre is inflated to

[dan the man]

For some reason my car has peak torque past 6000 rpm according to dyno...

sorry think your right, mine does. I meant near enouigh peak is before as flat curve.

from probably 3k 80% available ish...?

[gsuds]

Belated answer to Richard - yes I went for 40 profile GY on fronts - no problems at all. Academic now really.....

cheers

Graham

[Nick Graves]

I assume you mean pressure exerted by the tyre on the road and not pressure to which the tyre is inflated to

It's a rule of thumb so tyre pressure equates to pressure on the road. That's why your racing bike runs three times the pressure of your NSX. As does a truck with a similar tyre width.

[NoelWatson]

It's a rule of thumb so tyre pressure equates to pressure on the road. That's why your racing bike runs three times the pressure of your NSX. As does a truck with a similar tyre width.

Nick,

I don't see how the relationship works unless there is a linear relationship between tyre pressure and cross sectional area on the road.

[Midnight Blue]

As Noel says, the 9x square root of tyre pressure is only a rule of thumb.

The aquaplanning speed is rather more dependent on the properties of the water than whatever it is passing over it, so whether it is a car, bike, truck or aircraft the rule is more or less correct.

Most of the work on aquaplanning was done with aircraft in mind. There is far less public acceptance of air crashes and governments are more inclined to put up research funding.
Typically aircraft run with nitrogen filled tyres running at 190 -225 psi. This leaves the minimum speed for aquaplanning to be a problem at 125 -135 kts. This is just about landing speed for many commercial jets, which is really good news for us all when we are passengers next, as it is generally not an issue.
Not so good in the rare event of a rejected take-off which could be from 30 kts faster.

Cheers,

Andy