How much does the cornering speed effect the speed on the next straightaway?

I was running a few laps testing some changes to my Sauber C9, and watching the top speed continue to increase as the motor warmed up.

I recalled a discussion here about the cornering speed having a great effect on the top speed of a car.

Ever since I have had the ability to measure the top speed at the start/finish line, I have wondered about this effect.

The start/finish line is 8 foot 6.5 inches from the previous turn. The speed trap ends 2 foot past the start/finish line.

The cars are approaching the main straight from two different radius turns, therefore different cornering speeds

When the C9 was warmed up it had increased it’s top speed, at the start/finish line, to 20.5 f/sec in both lanes.

To try to understand this effect, I stopped the car at the eight foot mark, the distance to the start/finish line, and ran an acceleration test in both lanes.

The acceleration test’s top speed in both lanes at the start/finish line was 20.5 f/sec from a dead stop, the same as the top speed coming on to the straight at maximum cornering speeds.

I decided to try this experiment with one of my slower cars, the Porsche 911GT2. After a dozen laps it’s top speed was 14.7 f/sec.

I ran the same test stopping at the eight foot mark, same results in both lanes,14.7 f/sec from a dead stop.

Next came my big gun, the R&D Jag. After ten laps the speed was 24.1 f/sec.

I ran the same experiment again, stopping at the eight foot mark, and again the same results in both lanes, 24.1 f/sec from a dead stop.

The R&D Jaguar, running on the 20.5” diameter skid pad, has a top speed of 7.9 f/sec.

The same car travels through the 30.5” diameter inside lane 1 at a maximum speed of 9.7 f/sec.

The same car travels through the 38.5” diameter outside lane 2 at a maximum speed of 10.3 f/sec.

The

To answer the original question with all of this test information, the only conclusion I can make is that the cars are at their maximum speed some distance before the start/finish line and the cornering speed doesn‘t effect the car’s top speed at the start/finish line.

All the cars in these tests are geared for their best lap times, I believe the cars are reaching their

A previous test I did about adjustable braking, bore this out. I used the 8 foot front straight where the speed trap was at the 4 to 5 foot distance from the previous 24” radius turns, and the Jaguar was already at 95% of it’s maximum speed.

This is a link to that test.

Dave

I was running a few laps testing some changes to my Sauber C9, and watching the top speed continue to increase as the motor warmed up.

I recalled a discussion here about the cornering speed having a great effect on the top speed of a car.

Ever since I have had the ability to measure the top speed at the start/finish line, I have wondered about this effect.

The start/finish line is 8 foot 6.5 inches from the previous turn. The speed trap ends 2 foot past the start/finish line.

The cars are approaching the main straight from two different radius turns, therefore different cornering speeds

**, but the car’s top speed is the same in both lanes.**When the C9 was warmed up it had increased it’s top speed, at the start/finish line, to 20.5 f/sec in both lanes.

To try to understand this effect, I stopped the car at the eight foot mark, the distance to the start/finish line, and ran an acceleration test in both lanes.

The acceleration test’s top speed in both lanes at the start/finish line was 20.5 f/sec from a dead stop, the same as the top speed coming on to the straight at maximum cornering speeds.

I decided to try this experiment with one of my slower cars, the Porsche 911GT2. After a dozen laps it’s top speed was 14.7 f/sec.

I ran the same test stopping at the eight foot mark, same results in both lanes,14.7 f/sec from a dead stop.

Next came my big gun, the R&D Jag. After ten laps the speed was 24.1 f/sec.

I ran the same experiment again, stopping at the eight foot mark, and again the same results in both lanes, 24.1 f/sec from a dead stop.

The R&D Jaguar, running on the 20.5” diameter skid pad, has a top speed of 7.9 f/sec.

The same car travels through the 30.5” diameter inside lane 1 at a maximum speed of 9.7 f/sec.

The same car travels through the 38.5” diameter outside lane 2 at a maximum speed of 10.3 f/sec.

The

**photo**shows the corner where the exit speed was measured. The dark grey area is a two foot speed trap set up to measure the corner exit speeds**CONCLUSION**.To answer the original question with all of this test information, the only conclusion I can make is that the cars are at their maximum speed some distance before the start/finish line and the cornering speed doesn‘t effect the car’s top speed at the start/finish line.

All the cars in these tests are geared for their best lap times, I believe the cars are reaching their

__maximum speed__a lot sooner than I thought.A previous test I did about adjustable braking, bore this out. I used the 8 foot front straight where the speed trap was at the 4 to 5 foot distance from the previous 24” radius turns, and the Jaguar was already at 95% of it’s maximum speed.

This is a link to that test.

__http://slotcarillustrated.com/portal/forums/showthread.php?p=185569#post185569__Dave

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