: Concrete versus asphalt surfaces



s4ologist
08-18-09, 02:26 PM
I went to Plano, TX this weekend with my car (took the whole family). The concrete roads they have there allow for much better grip than the asphalt roads in San Antonio.
In 2 years and 10 months, we will be moving, but I am curious, where are concrete roads the norm? This is not the kind of thing I would have noticed before, but with 520 to the rears, asphalt feels slick (even in the summer). Here, there are times (mainly in cooler weather), where accelerating from 30 mph in 3rd leads to tire roasting. I basically can't floor the car in the first 3 gears here in San Antonio without loss of traction. I was getting minimal spin in 1st and 2nd in Frisco and Allen TX, where they had new concrete roads. It felt insane to be able to hook up like that.

I can see it now, explaining my criteria for a city to move to to my wife:

1. Job
2. Road surface composition
3. Family proximity
4. Climate

Anyone else noticed the difference between asphalt and concrete?

CIWS
08-18-09, 02:52 PM
http://www.dallasraceway.com/

Just outside Dallas, new track.

jwa999
08-18-09, 04:38 PM
Anyone else noticed the difference between asphalt and concrete?

Definitely. I was driving around in my porsche a few weeks back and the asphalt felt like no grip at all. Car felt very floaty. Was 105+ degrees. West of Forth Worth. Tires would spring into action delayed, was just scary.
Then on hwy 82 between sherman and paris there are some excellent smooth concrete surfaces where the car flies.

Hans.

SlvrBullIT
08-18-09, 06:56 PM
New concrete has really good grip....and incidently more wear. Some roads that are concrete, been around awhile and get worn in get slippery in light rain especially it they are without grooves. Worn asphalt is just bad.... hot, cold, dry wet...yuck

Short-Throw
08-18-09, 08:33 PM
Asphalt can have sealer incorporated into the mix which can become slick as well. Many tracks have segments and patchwork of asphalt, they are usually the slickest. Concrete is more expensive to lay.

nc09v2
08-18-09, 10:54 PM
I think the age of the road has a lot to do with traction.

Older concrete or asphalt are smoother and provide less traction. New of either is generally much better.

Agree that new concrete with a little texture from being poured works very well, whereas asphalt is compressed by a steam roller which provides minimal texture and also probably less traction.

We have a lot of relatively new roads where I live, but the V still requires concentration to launch in 1st gear regardless of road surface.

s4ologist
08-20-09, 11:29 AM
I have noticed that the age of the surface plays a significant role. In Allen, there was some really new concrete that was grippier than anything here in San Antonio, although there are some new asphalt roads that are pretty good.

As far as launching goes, I have never even attempted it. If I floor the gas in 1st at idle or any other RPM, it roasts the tires. The only exception to that has been my experience in Allen. I was able to hit it in first at 10MPH from a roll and get minimal wheelspin, then chirp 2nd with a crisp shift (the concrete was less than 6 months old, though). In Lewisville, on older concrete I spun most of the way through 2nd gear. Maybe in Allen (or on a track), I could try to take it up to 2K or so and launch it. My last car (modded B5 Audi S4) had 2 more wheels putting power down, and 200 less HP/TQ, so the search for the "perfect surface" really didn't happen.

With prior cars, adding passengers meant less real acceleration. Now, putting 3 adult passengers in the car (say, on the way to lunch), actually lets me be more liberal with the gas pedal. I wonder if anyone has done the 1/4 with a couple of bags of sand in the trunk for a better launch?

ewill3rd
08-20-09, 10:14 PM
Not many cities do their streets in concrete because of the expense.
It seems like a much better road surface to me and I much prefer driving/riding on it.
I have been on some nice asphalt roads too. They take more maintenance than concrete but they are much cheaper to build and maintain overall I think.

A lot of interstate highways are made of concrete because it is more durable and requires maintenance.

There are some concrete surface streets around here but they patch them with asphalt.

The real thing you need to watch out for is what us motorcyclists refer to as "tar snakes".
Those are the cheesy strips of tar they lay on cracks of all types of roads and sometimes they make matters worse by sprinking gravel on them.
They use it as an excuse to not have to resurface roads but it makes them deadly to motorcycles and none to good for cars, particularly in wet weather.
They are like ice at times and you don't even think about it until it is too late.

Mike 09 V
08-22-09, 06:24 PM
In Arizona we have been paving over the concrete with asphalt because of the noise. Asphalt is way way quieter than the concrete. Also, we don't get much rain here and oil dripping onto the asphalt is absorbed and the first rain and the first hours of wet streets the oil floats to the top and the streets are treacherous.

ewill3rd
08-23-09, 01:14 PM
Where I lived in CA was like that, it wouldn't rain all summer then the rain would come and the roads were like ice.
I saw a 24' truck dancing down the interstate one day just smashing the crud out of a Volvo on just such a day.

concorso
08-23-09, 01:44 PM
Luckily here the cracks in the road are too wide to repair with tar snakes. Ive heard a few mean stories about them.

whisler151
08-24-09, 11:34 AM
Plano roads rule!