My car wanders at high speed - is it normal?
Discussion
quote:
All fine now.
Geometry reset and different tyres (Toyo). Suggest all tuscan owners change their tyres to the new factory spec as it makes a HUGE difference.
Rgds
RR
RRTuscan,
Interesting to hear your comments.
Where did you get yours done .... and if you don't mind how much are we talking about? Can the work be covered on the Warranty??? How long does it take??
I've just got my car back from its running in service. Gave it a little bit of a test on the motorway at the weekend and didn't have any problems. However, I have (before the service) experienced some tram lining, and I would like to make sure that I don't have any issues when going at speed!!!!
Edited by sandman on Monday 14th January 14:07
The tyres are thicker and not only improve the handling but they may help the wheels buckling (touch wood). The geometry is supposedly the new setup as per factory recommendations.
I had it all done as part of a service so the geometry was free. Speak to Brian at Fernhurst about what can be done.
Tramlining does still occur on lorry tracks but no where nearly as often or severely.
Have fun
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Has anyone else had probs over say 110+ whereby the car is all over the road and feels like its going to break loose any moment?
Ive always put it down to the 18" wheels but I now think it must be something else.
Apparently the 'S' is totally different in terms of suspension mountings etc. Is this because all us Red Rose option people found high speed driving more than a bit freaky.
I'd be interested in other drivers opinions.
This sounds to me like an even more severe case of the problem found with Griffiths. On a long Autobahn run I pushed my Griffith 500 to 164 mph indicated. Above 150 mph it felt a little unglued with the car beginning to exibit wander. Above 160 mph it became a white knuckle ride. I lifted off very, very gently to allow the speed to bleed off .... even so it felt like the car wanted to corkscrew. 3weeks later at the motorshow I spent 10 minutes or so talking to Peter Wheeler who freely admitted that above about 135-140 mph rear end lift became noticeable on the Griffith and at 160 mph was quite severe! Now, front end lift is bad enough (remember the horror stories of the Miura) but rear end lift is seriously bad news. If it steps out of line I don't care how good a driver you may be, you will not control it... period!!! You may recall the number of Audi TT drivers killed in Germany by exactly the same problem - rear end breakaway at around 110 mph whilst turning off on gentle exit curves from autobahns. That prompted a total recall of TT's to fit hastily engineed lip spoilers on the rear and revised suspension/damper settings.
It worries me that the Tuscan, developed with some wind tunnel input, should display such alarming tendencies. My 4.5 Cerbera shows commendable high speed stability having run to 185+ mph with only a small degree of lightening of the steering (and a bonnet that strained so hard against the latches I was expecting it to self destruct).My advice to Tuscan owners is to be very, very careful. This is far from a trivial problem and going slower until some serious investigation is done sure beats the hell out of winding up dead.
When I looked into this last year I was surprised how sensitive this is to the car's pitch attitude, and also to the front chin clearance. You may well find that dropping the front ride height an inch or lifting the rear half an inch makes a big difference, and at these speeds the extra chin 'spoiler' could also make a noticeable difference. You may find it counter-intuitive, but putting more weight in the boot makes this problem worse not better. If you change the ride heights, remember to check and correct the geometry afterwards.
Cheers,
Peter Humphries (and a green V8S)
Cheers,
Peter Humphries (and a green V8S)
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the Chimaera's chin spoiler makes little difference below 120mph, but above that speed the car starts to fly without it.
Oh!
, and I thought it was to produce a pressure drop across the radiator to ensure a cooling air flow at speed. That's what I thought I was doing when I put mine back on anyway 
. Can anybody clarify please?quote:
Oh!
You're both right, although the major effect appears to be one of enhanced cooling rather than stability. My Griff 500 shows no enhanced stability with or without the spoiler up to 140mph, although it immediately ran 5C hotter when I last tore the spoiler off on a pheasant
Pete
The cooling impact is only going to have any effect when the car is moving quickly (obviously a spoiler will have no impact when the car is stationary). Since most overheating occurs when the car is stationary or travelling slowly, the spoiler isn't much practical help.
E.g., if you join a motorway queue, the chin spolier might have given you a lower starting temp from which to heat up, but that advantage will be overcome within a couple of minutes at most.
E.g., if you join a motorway queue, the chin spolier might have given you a lower starting temp from which to heat up, but that advantage will be overcome within a couple of minutes at most.
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The cooling impact is only going to have any effect when the car is moving quickly (obviously a spoiler will have no impact when the car is stationary). Since most overheating occurs when the car is stationary or travelling slowly, the spoiler isn't much practical help.
Maybe it is because the spoiler is there encouraging airflow through the radiator at speed that we don't also suffer overheating when the car is moving? Is the airflow through the radiator without the spoiler sufficient to keep the engine cool on the hottest of days? After all, there is more heat to be dissipated when the engine is working harder. Seemed to be ok on mine without it but I didn't try it on a stinking hot day so it is presumably marginal.
Either way, it's a bloody nuisance because it is so easy to knock it off. My car is not the best for stability at speed either; with or without the spoiler.
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