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Originally posted by Kremithefrog:
You are NOT experimenting with the right amount of wheel spin. Wheel spin is not what you want.
wrong
i ran 16.3s on a bald set of kumho 711s, with wheelspin
i ran 16.5s (in cooler weather) on a new set of azenis, with little or no wheelspin, also my 60' times were about .1 sec slower
i have timeslips to prove this
Russell
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Originally posted by Blk560:
Originally posted by Kremithefrog:
the only 0-60 vs. 5-60 times I can find have the 5-60 being faster
You may want to review the last, say, 10 years of Car & Driver and come back with a better answer...
I don't get car and driver, and I wouldn't call one source a definitive answer...
Anyways that wasn't my answer at all, that was just a reply to his comment about 0-60 vs. 5-60 times while we were really just discussing the 0-60 aspect of things at first... 5-60 brings other factors in to play as well, not just the launch, which is what this is all about. And how do you know how they do their 5-60 times? They may do these a certain way to not try to make them be the fastest possible 5-60s, just a way to compare what a car does in real life situations.
98.5 SVT
91 Escort GT (almost sold)
96 ATX Zetec (i brake to watch you swerve)
FS: SVT rear sway bar
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Originally posted by Russell-3L:
Originally posted by Kremithefrog:
You are NOT experimenting with the right amount of wheel spin. Wheel spin is not what you want.
wrong
i ran 16.3s on a bald set of kumho 711s, with wheelspin
i ran 16.5s (in cooler weather) on a new set of azenis, with little or no wheelspin, also my 60' times were about .1 sec slower
i have timeslips to prove this
You don't understand it though, the wheel spin itself is NOT what is making you move. Possibly having them not hook great but allowing the engine to keep it's revs up does get you moving... the bald tires may also have helped out on the rest of the run... and even if the weather is colder, there is still other factors that come into play.
LISTEN TO THIS::: WHEEL SPIN DOES NOT MAKE YOU MOVE, THOUGH IT MOST LIKELY WILL BE INVOLVED IN YOUR MOVEMENT. Understand what I'm saying?
98.5 SVT
91 Escort GT (almost sold)
96 ATX Zetec (i brake to watch you swerve)
FS: SVT rear sway bar
WTB: Very cheap beater
CEG Dragon Run - October 13-15
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Originally posted by Kremithefrog:
Originally posted by Russell-3L:
Originally posted by Kremithefrog:
You are NOT experimenting with the right amount of wheel spin. Wheel spin is not what you want.
wrong
i ran 16.3s on a bald set of kumho 711s, with wheelspin
i ran 16.5s (in cooler weather) on a new set of azenis, with little or no wheelspin, also my 60' times were about .1 sec slower
i have timeslips to prove this
You don't understand it though, the wheel spin itself is NOT what is making you move. Possibly having them not hook great but allowing the engine to keep it's revs up does get you moving... the bald tires may also have helped out on the rest of the run... and even if the weather is colder, there is still other factors that come into play.
LISTEN TO THIS::: WHEEL SPIN DOES NOT MAKE YOU MOVE, THOUGH IT MOST LIKELY WILL BE INVOLVED IN YOUR MOVEMENT. Understand what I'm saying?
understand what me and everyone else are saying, the right amount of wheelspin allows an engine to get in its peak power range, therefore producing faster times. not all wheelspin is good, the wheelspin you would get with 2 spare tires on the front of a turbo 3L SVT launching at 6K would not be good. like i said, the right amount of wheelspin will allow the engine to get put in the powerband faster, thus producing better times
Russell
Oval Port 3L Nearly Done
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Originally posted by Kremithefrog:
Originally posted by Russell-3L:
Originally posted by Kremithefrog:
You are NOT experimenting with the right amount of wheel spin. Wheel spin is not what you want.
wrong
i ran 16.3s on a bald set of kumho 711s, with wheelspin
i ran 16.5s (in cooler weather) on a new set of azenis, with little or no wheelspin, also my 60' times were about .1 sec slower
i have timeslips to prove this
You don't understand it though, the wheel spin itself is NOT what is making you move. Possibly having them not hook great but allowing the engine to keep it's revs up does get you moving... the bald tires may also have helped out on the rest of the run... and even if the weather is colder, there is still other factors that come into play.
LISTEN TO THIS::: WHEEL SPIN DOES NOT MAKE YOU MOVE, THOUGH IT MOST LIKELY WILL BE INVOLVED IN YOUR MOVEMENT. Understand what I'm saying?
Your right, wheel spin does not make you move. If wheel spin was the only single factor in how fast you accelerate, then you are right.
Your clutch slipping is the same as a tire slipping. If your clutch is slipping, you are not launching as fast as you can.
If your engine put all the power out linearly, then no slip would be the fastest acceleration. Look at a dyno plot. Since torque and HP are at the higher RPMS, something has to slip (Clutch, Tires, or both) to let the engine RPM rise to a place with significant power to get the fastest acceleration. If you really want no slip, put the car in gear, engine off. Start in gear and see how fast the car accelerates.
The above is NOT true for Steam or electric motors. Electric and steam develop max torque at 0 RPM. So wheel or clutch slip is detrimental to fast acceleration for these engines.
So, with a typical internal combustion engine, something has to slip to get you going. The trick is to balance the slip (tires or clutch) so that you develop both the best engine RPM for Torqu and HP and minimizing slip.
Having said all that, AWD requires more clutch slippage for launch because it takes too much torque to spin the wheels in most cases. RWD can utilize wheel spin to some degree and save wear and tear on the clutch. Tires are easier to change than clutches anyway.
And as I stated earlier, very powerful cars accelereate hard enough that most of the weight is reansfered to the rear tires and AWD could not be used to a great advantage since the front wheels are not loaded enough to make much addition to acceleration. I notice many RWD cars (pro stock, for instance) that actually lift 1 or 2 front wheels of the ground on a hard run. AWD would not help their 1/4 mile times at all. This is why FWD is limited in 1/4 mile times. The harder you accelerate, the more unloaded the fronts become. You will never see 8 second FWD cars because the physics are wrong for that configuration.
Again, AWD will lauch faster in 12 inches of snow though. 
My name is Richard. I was a Contouraholic.
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Originally posted by Kermithefrog:
I don't get car and driver, and I wouldn't call one source a definitive answer...
If you have a better, more comprehensive source that has tested thousands of cars by the same method--whose staggering majority of test results have 5-60 street-start lagging 0-60--then, by all means, bring it. For now, it seems all you have is conjecture. Gotta do better than that, and test data is a start.
Quote:
Anyways that wasn't my answer at all, that was just a reply to his comment about 0-60 vs. 5-60 times while we were really just discussing the 0-60 aspect of things at first...
I don't care what your comment was in response to. It was erroneous based on reams of data and you're being called on it.
Quote:
5-60 brings other factors in to play as well, not just the launch, which is what this is all about. And how do you know how they do their 5-60 times? They may do these a certain way to not try to make them be the fastest possible 5-60s, just a way to compare what a car does in real life situations.
C&D is quite transparent on how they extract their test data. Every now and again they run an article outlining exactly how and why they test the way they do. I don't feel like digging one of those articles out of my archives tonight, and, besides, it would probably be beneficial for you to dig one up for yourself. C&D's aim in conducting the 5-60 street start test is to help typify a real-world launch without the mega-rpm clutch-drop, tire-roasting hysterics which gives many vehicles an instant advantage. Five mph is picked because it's an easy speed to maintain regardless of shift type...all they do is nail the throttle--controlling wheelspin where necessary--and shift/drive normally as in any other acceleration run.
Torque-rich motors hooked to slushboxes generally have less disparity between 0-60 and 5-60 times as do high-winding, low-torque mills hooked to manual gearboxes, for obvious reasons (I assume no explanation is needed here?). They don't--as you imply--intentionally try to make 5-60 times slower...they are slower because that's the way it is.
B. Riley
Melbourne, FL
'01 Camry LE V6/5-spd
Was: '00 Black/Tan SVT Contour #560 - Sold 3/26/03
Before that: '95 Champ/Blue Contour GL V6 ATX
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I know all this,,, my only point was wheel spin does not make you move, though it does have to happen to make you move quick,, but that wasn't what was in debate....
Now as far as 8sec FWD cars, go look at the meguair's focus and the guy running the pro srt4. Both run 8sec times and I've heard they're running 7sec now.
There are ways to get traction with FWD, wheelie bars can help keep the front loaded on FWD cars, among other things.
98.5 SVT
91 Escort GT (almost sold)
96 ATX Zetec (i brake to watch you swerve)
FS: SVT rear sway bar
WTB: Very cheap beater
CEG Dragon Run - October 13-15
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Originally posted by Blk560:
Originally posted by Kermithefrog:
I don't get car and driver, and I wouldn't call one source a definitive answer...
If you have a better, more comprehensive source that has tested thousands of cars by the same method--whose staggering majority of test results have 5-60 street-start lagging 0-60--then, by all means, bring it. For now, it seems all you have is conjecture. Gotta do better than that, and test data is a start.
Quote:
Anyways that wasn't my answer at all, that was just a reply to his comment about 0-60 vs. 5-60 times while we were really just discussing the 0-60 aspect of things at first...
I don't care what your comment was in response to. It was erroneous based on reams of data and you're being called on it.
Quote:
5-60 brings other factors in to play as well, not just the launch, which is what this is all about. And how do you know how they do their 5-60 times? They may do these a certain way to not try to make them be the fastest possible 5-60s, just a way to compare what a car does in real life situations.
C&D is quite transparent on how they extract their test data. Every now and again they run an article outlining exactly how and why they test the way they do. I don't feel like digging one of those articles out of my archives tonight, and, besides, it would probably be beneficial for you to dig one up for yourself. C&D's aim in conducting the 5-60 street start test is to help typify a real-world launch without the mega-rpm clutch-drop, tire-roasting hysterics which gives many vehicles an instant advantage. Five mph is picked because it's an easy speed to maintain regardless of shift type...all they do is nail the throttle--controlling wheelspin where necessary--and shift/drive normally as in any other acceleration run.
Torque-rich motors hooked to slushboxes generally have less disparity between 0-60 and 5-60 times as do high-winding, low-torque mills hooked to manual gearboxes, for obvious reasons (I assume no explanation is needed here?). They don't--as you imply--intentionally try to make 5-60 times slower...they are slower because that's the way it is.
Just because C&D is your auto-god doesn't make it mine. And I care to dig up these C&D stats just as much as you care to post them. 
There are so many different factors that go into a 5-60 times I wouldn't even use it in a comparison.... ESPECIALLY in a discussion that has nothing to do with rolling starts. 
98.5 SVT
91 Escort GT (almost sold)
96 ATX Zetec (i brake to watch you swerve)
FS: SVT rear sway bar
WTB: Very cheap beater
CEG Dragon Run - October 13-15
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Let me further explain as far as the 5-60 times go as my posts are starting to become as useless as your's blk560. If you're gonna rev up and then go for a 0-60 but not do the same for a 5-60,, then that right there makes them useless in a comparison for this discussion,, though yes useful for real life situations. I think this topic has been discussed enough though and MOST of us understand how it all works, though we say it different. Though if you care to discuss 5-60 times (for whatever reason) with me anymore shoot me a PM, now if you wanna keep discussing the original subject, than go ahead and post it here.
98.5 SVT
91 Escort GT (almost sold)
96 ATX Zetec (i brake to watch you swerve)
FS: SVT rear sway bar
WTB: Very cheap beater
CEG Dragon Run - October 13-15
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Originally posted by Kremithefrog:
Just because C&D is your auto-god doesn't make it mine. And I care to dig up these C&D stats just as much as you care to post them.
In what part of my discussion have I worshipped C&D? Can you focus on intelligently discussing the subject with facts and data rather than dealing with conjecture and crying foul when you're proven wrong?
Do you think these test guys sit around blowing bubbles all day, dreaming up numbers? Do you think your speculation is more valid than test results from thousands of vehicles using the same, well-documented methods and yields staggeringly consistent results? Just because you choose not to view the facts does not make them invalid.
Quote:
There are so many different factors that go into a 5-60 times I wouldn't even use it in a comparison.... ESPECIALLY in a discussion that has nothing to do with rolling starts.
If you had understood correctly from my prior post, the street-start test actually greatly reduces the complexity of getting acceleration times by de-emphasizing or removing many of the factors that make consistent standing-start measurements difficult to achieve. So, actually, there are fewer factors at work in the 5-60 test. Neither is invalid in the real world, but 5-60 is definitely more repeatable because of its simplicity.
As I already stated, I don't care why we're discussing 5-60 times and whether it's relevant to the thread topic. I am simply explaining that you are wrong, and why, as you have requested:
Quote:
the only 0-60 vs. 5-60 times I can find have the 5-60 being faster, PLEASE show me different.
When you have cold, hard facts disputing years of test results, then I will concede the point.
B. Riley
Melbourne, FL
'01 Camry LE V6/5-spd
Was: '00 Black/Tan SVT Contour #560 - Sold 3/26/03
Before that: '95 Champ/Blue Contour GL V6 ATX
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