If you change to a substantially different tire than what came on the car, you are then faced with doing what the factory NVH guys do, for just one car, with no real resources.
The supposed advantage of low profile tires is that are stiffer, in a handling sense, than high profile tires. In practice this actually takes the tire too far away from the impact harshness and roadnoise of the standard tire, when fitted by an OEM, and the stiffness of the tire is then dialled back to preserve NVH. This results in the ludicrous situation where people are buying factory-fitted LP tires for their new cars and mainly gaining styling, and problems.
In the aftermarket there is no particular reason to soften the tire off for NVH, so at least the original raison d'etre remains, the tire should be stiffer, all else being equal, than its HP stablemate . But yes, NVH will suffer.
Incidentally and far more confusingly, the coning stiffness and modal performance of your aftermarket wheels may be affecting both the handling and NVH performance you get.
Cheers
Greg Locock
New here? Try reading these, they might help FAQ731-376
Transmit to the ear of the driver and passengers. The reason is that while test driving a SE Camary with low profile tires, at high speeds of about 65 to 75 mph road noise was more pronounced than at 40 mph and lower speeds. Handling and acceleration were good but that road noise especially when changing lanes was like hearing a passing passenger train.
Many years ago, like when 60 series where the hot low profile set up I put a set of 205 60 15 Toyo R600s on my heavily modified VW Type 3 Wagon. It had twin by twin choke Webbers and a 2" exhaust with minimal mufflers and made about 130hp at the wheels. I also fitted a Rolla Roof Rack.
Neither the tyres nor the roof rack made any noticeable noise at any speed in that car. Also the radio was so poor I could hardly hear that either.
A few years latter I used the same brand, size and model of tyres and the same roof racks on a Toyota Cressida and both where as noisy as hell.
Another incredible aspect was that the noise got a lot worse with increased speed. Man. What a surprise. Yes. Please insert sarcasm smiley here.
Regards
Pat
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