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What good is handling in corners if you always get passed on the straights?

If anybody watched the Bathurst 12 Hour race last weekend, this is exactly what the Audi guys were saying. They were faster on the top of the hill [curvy sections]. The Mercs, McClaren, Bentley's, and GTR would then blow by them on the long straight. The "balance of performance" was there with roughly equivalent lap times when qualifying, but in race conditions they said they didn't have much of a chance to win. Of course they weren't there to have fun, they were there to win.

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Old 02-15-2016, 07:43 PM
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That was great, having owned a 65 vette for many years, before it was stolen, it was great to see the two of you playing your strengths and weaknesses.
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Old 02-16-2016, 07:47 AM
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I think all of this back and forth has well established a better driver almost always beat a "faster" car. That being said, hp ain't everything. The OP showed a 1960s muscle car vs. a Porsche. The Firebird had better show up with TONS more hp because a car like that was never designed to compete on a road course. A nose-heavy brick with a solid rear end and non-boxed frame is probably doing quite a bit of flexing trying to negotiate those corners. And if handling doesn't matter, look at the giant-killers Lotus and Porsche of the 1950s and 60s beating Ferraris and Jags.

HP doesn't mean too much if you can't use it. How effectively is that getting to the ground? TBD or LSD used? Center of gravity, wheel/tire size, etc.? If traction doesn't matter, then what about Audi in the early 80s or Mitsubishi and Subaru in the early 2000s?

This is one of my favorite examples, EVO vs. Z car. On paper the Z is lighter, more hp, and has better aero...but the EVO is quicker due to better traction and handling.

Sports Car Comparison - 2011 Nissan 370Z vs. 2011 Mitsubishi Lancer Evo GSR

And one of my favorite "better driver" examples, he makes it look soooo easy. The dude is fearless:

https://www.youtube.com/watch?v=eSJ-HzNWJGM
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Old 02-16-2016, 09:25 AM
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jadewombat~ that last one is very similar to this one of Sabine Schmitz in a VLN race. She knows the track and car so well, and knows no fear, even in a light rain.

https://www.youtube.com/watch?v=ufzdL1JaEKM
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Old 02-16-2016, 09:40 AM
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To turn the OP's question on its head:

What good is HP, if you always get passed in the tight sections?

--DD
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Old 02-16-2016, 11:26 AM
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I wish I could find some youtube videos of the original Trans Am race series when the two classes ran together and the little Porsches in the lower class regularly harassed the bigger cars in the premier class.
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Old 02-16-2016, 12:25 PM
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Quote:
Originally Posted by sugarwood View Post
What do you think was the weight difference between the Muscle and your 2.7 Porsche ?
I have a 211HP 2.5L short stroke, single plug, 46mm PMO's. My car weighs ~2100 pounds. I'm not sure what those muscle cars weigh.
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Old 02-16-2016, 01:40 PM
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Quote:
Originally Posted by Green6 View Post
jadewombat~ that last one is very similar to this one of Sabine Schmitz in a VLN race. She knows the track and car so well, and knows no fear, even in a light rain.

https://www.youtube.com/watch?v=ufzdL1JaEKM
Yup, she's a great one. I've loved the van video for years.

In the arms-race of hp where american V8s are achieving higher and higher hp numbers, again, it's important to understand useable power. My buddy's Datsun 280 with an LS crate motor swap and limited-slip, he spins out near 10:00. I would've probably done the same thing.

https://www.youtube.com/watch?v=iAz3KXl2IfA&feature=youtu.be
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Last edited by jadewombat; 02-17-2016 at 06:09 AM..
Old 02-16-2016, 03:45 PM
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Quote:
Originally Posted by Dave at Pelican Parts View Post
To turn the OP's question on its head:

What good is HP, if you always get passed in the tight sections?

--DD
That's a dubious statement. Based on the videos posted, passing in the curves in the exception, not the rule. It is very hard to pass in the curves.
The smaller generally catches up, but rarely passes. He is just stuck behind. And on the case the smaller does pass, he often gets passed right back on the next straight.

Based on the evidence offered here, it's evident that power trumps weight, which is probably why pro drivers use huge HP, and not 50hp featherweight go-karts.
The post below basically confirmed all this from a professional point of view:

Quote:
Originally Posted by Green6 View Post
If anybody watched the Bathurst 12 Hour race last weekend, this is exactly what the Audi guys were saying. They were faster on the top of the hill [curvy sections]. The Mercs, McClaren, Bentley's, and GTR would then blow by them on the long straight. The "balance of performance" was there with roughly equivalent lap times when qualifying, but in race conditions they said they didn't have much of a chance to win. Of course they weren't there to have fun, they were there to win.
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Last edited by sugarwood; 02-17-2016 at 08:53 AM..
Old 02-17-2016, 08:31 AM
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Quote:
Originally Posted by sugarwood View Post
That's an incorrect statement. Based on the videos posted, passing in the curves in the exception, not the rule. It is very hard to pass in the curves. The 911 generally catches up, but rarely passes. He is just stuck behind. And on the case the 911 does pass, he often gets passed right back on the next straight.

YMMV, and I'm not competitive racer, but based on the evidence offered here,
I've concluded that power clearly trumps weight, and there is a reason pro drivers use huge HP, and not 50hp featherweight go-karts.

The post below basically confirmed all this from a professional point of view:
Technically, this is incorrect also. It all comes down to the track configuration.
Old 02-17-2016, 08:49 AM
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Quote:
Originally Posted by sugarwood View Post
That's an incorrect statement. Based on the videos posted, passing in the curves in the exception, not the rule. It is very hard to pass in the curves. The 911 generally catches up, but rarely passes. He is just stuck behind. And on the case the 911 does pass, he often gets passed right back on the next straight.

YMMV, and I'm not competitive racer, but based on the evidence offered here,
I've concluded that power clearly trumps weight, and there is a reason pro drivers use huge HP, and not 50hp featherweight go-karts.

The post below basically confirmed all this from a professional point of view:
Quote:
Originally Posted by Plavan View Post
Technically, this is incorrect also. It all comes down to the track configuration.
Very true. I can pass and stay ahead of many varieties of Cup Cars at Sears Point with my race car. With a 150 to 200 HP deficit I am not passing them on the straights! Thunderhill, on the other hand, is much more difficult. I can run similar lap times but passing and making it stick is much more of a challenge. Horsepower matters more at Thunderhill than it does at Sears Point.
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Old 02-17-2016, 10:01 AM
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As you mentioned the type track has a lot to do with it and it's power to weight not horsepower. Then it's stay in the other guys mirrors, look for his weak point and be ready to pounce.
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Old 02-17-2016, 12:07 PM
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Quote:
Originally Posted by sugarwood View Post
That's a dubious statement. Based on the videos posted, passing in the curves in the exception, not the rule.
No more dubious than the original statement. The thing is, if you are "always" getting passed, the problem is almost certainly not with the car...

--DD
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Old 02-17-2016, 12:50 PM
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Old 02-17-2016, 01:24 PM
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Sugarwood, in races with cars of equal horsepower, most of the passing is done in the braking zone before the corner.

This is equally effective for small cars attacking high hp cars, as well as any car of equal hp. It comes down to race-craft.

All things begin equal, HP just gives an advantage to the lesser skilled driver.

If you want to pick the best mix of hp and weight, as has been said, a big factor will be knowing which tracks you will run at.

Lemans and Daytona both reward big hp due to top speed more than acceleration.

Other tracks like the old formula one track at St. Jovite that I drive on rewards perfect lines more than hp, because so much of the track is the twists where you can't take advantage of any hp advantage, and, in a race, a good under hp driver would time the pass and track position to take away the high hp driver's drive.

Likewise the high hp driver would try to do the same to take away the lower hp driver's momentum.

What I find sad for professional racing is that at one time, the race organization used to leave it up to the teams to decide how to go fast. Now with balance of performance rules, they keep it so close that it is rare that you will ever see these old underdog battles.

The reason that teams like Shelby and Pensky opted for big truck engines back on the day was that they were more likely to last to the end in endurance races. For sprint races smaller engines gave the advantage of lighter weight and sometimes at lower hp, but the driver and engine had to work a lot harder.

Then there is the other factor of power to weight.
Big hp in a heavy car vs. lower hp in a lighter car, but both with the same percentage of power to weight is a different variable again.

I will agree with you that it is easier to go fast with a high hp car, but I will also state that you don't learn much.

When I road raced motorcycles I started with a relatively high hp 4 cylinder 500cc two stroke.
I was great at out accelerating and out braking the competition.

It wasn't until a few years later when I did an 8 hour endurance race on light a 600cc single cylinder bike against the higher hp super bikes on a twisty Blackhawk farms circuit that I actually learned to go fast.
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Last edited by wayner; 02-17-2016 at 01:50 PM..
Old 02-17-2016, 01:47 PM
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Quote:
Originally Posted by sugarwood View Post
Based on the evidence offered here, it's evident that power trumps weight
This makes my eye twitch a bit.
F=MA
A=F/M
acceleration=force/mass
torque is a twisting force that causes rotation
hp is calculated from torque, so for now lets ignore HP given hp is calculated based on torque.
so
A=torque/mass

so, a 2000lbs 911 with 200lbs-ft torque will accelerate at...
A=200/2000= 0.1 (lets not worry about units)

Now, lets look at a 4000lbs, 400lbs-ft Mustang.
A=400/4000=0.1

So more torque will not accelerate faster (all other factors equal).
What you need to look at is power to weight. Both above cars have an identical power to weight, so identical acceleration.

Now, nothing is quite this simple. gearing, drag, lateral grip, breaking, car setup, driver, tires, gears... etc. all play into it. Some tracks also have corners that are far more open to allowing a pass, and very limited straights.

Again, where I go, handling cars, not power cars, rein supreme. Mind you, a handling/cornering being the same, the car with more power will win. But than this is no news.

Quote:
Originally Posted by wayner View Post
The reason that teams like Shelby and Pensky opted for big truck engines back on the day was that they were more likely to last to the end in endurance races. For sprint races smaller engines gave the advantage of lighter weight and sometimes at lower hp, but the driver and engine had to work a lot harder.
The Shelby Daytona and the Ford GT40 were famous for this. Their huge displacement engines made so much torque that they could keep in higher gears, and keep revs down. This reduced stress on the engine, and also saved on fuel, despite the displacement. The smaller, lighter low displacement Ferraris needed to rev for thier power, reducing durability, and increasing fuel consumption. Kind of like when Top gear compared a prius on the track to a e90 M3. The prius went as fast as it could and the M3 just matched speed. The Prius used more fuel. The v8 hardly broke a sweat. Similar strategy with the Daytona and GT40. Match the pace of the Ferraris and conserve.

In modern racing, to win you need cornering/handling, and power.

Quote:
Originally Posted by jadewombat View Post
The Firebird had better show up with TONS more hp because a car like that was never designed to compete on a road course.
Yup. In some of the videos where the car walks (runs) away on the straights, you know they are playing with WAAAAYYY more hp than the other car. The "underpowered" car that is nipping at their bumper and struggling to get by, probably has a much less advantageous power to weight ratio. Would be interesting to see numbers.

Mark Donahue, who raced the 917-30, was once asked how much hp is enough. His response was something to the effect of "I have enough hp when I can spin my wheels from corner exit to corner entry on the straights."

What is super cool about the 911, and a small part of why why many of us here love them at the track, is that they tend to punch above their weight when driven well. The rear engine both allows later braking, and earlier power on after the throttle. As demonstrated in some of the videos, this allows the car to "punch above it's weight (power)".
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Last edited by gliding_serpent; 02-17-2016 at 03:28 PM..
Old 02-17-2016, 02:56 PM
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Thats a great write up

Here is one of my favourite videos.

At the beginning he dices with a similar car to the one he is driving but with obviously more power (or maybe he is just running amor defensive line and not getting as good a run off the corners due to the heat behind??) . You can see the give and take.

After the midway point of the video things get interesting. (would have been even more interesting if there was a rearward facing camera to see the pressure he was under from behind as he was trying to both drive defensively yet aggressively enough to get the car ahead).

Described as Patrick Long in a car 1/2 the horsepower of the 935s he dices towards the end.
(that twice the hp, TWICE! so Long's 300 hp vs. their 600hp. or maybe 350hp vs. 700hp???)


I'll go out on a limb and suggest that Long has more skill while those 935 drivers as well as that duck tailed RSR at the beginning all have more hp.

Professional driver vs. not professional drivers.

EDIT: I just realized that this is a different video. I'll post a link if I find the one form 2015 that I meant to post

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Last edited by wayner; 02-17-2016 at 05:25 PM..
Old 02-17-2016, 04:11 PM
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Let's not forget that most of those guys are out there to have their car seen and not drive them anywhere near its potential. Patrick, on the other hand, is able to drive the car close to its potential without undue risk.

It's kind of like watching Canepa be a crazy man and pass all the cars in his races except for Patrick is not crazy.
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Old 02-17-2016, 05:07 PM
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I'll bet that they use all of the gas pedal though
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Old 02-17-2016, 05:20 PM
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I'll bet that they use all of the gas pedal though
Maybe. But what is the boost set to? Probably a very conservative BAR setting. Look how easy most of them are taking it in the corners. It looks like a Sunday drive!

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Old 02-17-2016, 05:27 PM
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