Poll: What's faster? Automatic or Manual Transmission? Help clear the debate...

[notfred]

The fastest cars in the world in the 1/4 mile are all automatic.

 

[Demon-Xanth]

Laust: Notice that higher classes tend to run Lenco, Richmond, or Jerico 4-6 speed clutchless manuals. The reason that automatics take precedence over the T5/T56 transmissions is that the autos have planetary gear sets that have three contact points instead of one. They can take more torque. Richmond and Jerico transmissions are replacing Lencos in Pro Stock because of the weight difference. Planetary gear sets aren't light.

I seem to remember the phrase used in Hot Rod magazine during an interview: "If you're not using a Lenco, you're losing" (in reference to using a TH-400 w/ a clutch, as people have done in the past)


Automatics are faster in turbo diesel trucks because the torque converter allows the engine to stay in a higher power band (on the boost). And shifting 4-5 times on your way to 60 takes time. Why do people (like my dad) get manuals? They don't create as much heat when climbing with loads. And they can use the engine to control thier speed more effectively.

Turbo cars can easily have the manual be faster if the driver powershifts instead of lift throttle shifting.


Case in point:
Take the case of the 5.9 R/T Dakotas vs. the 4.7+5 speed. The quarter mile performance is so close, that it's always a good race and you never KNOW who is going to win. The 5.9 isn't available with a 5 speed because the 5 speed used (NV-3500) is rated for 300LB/ft. The 5.9 makes 260HP-350LB/ft. Clearly too much. The 4.7 makes 235HP-295LB/ft. Just under. So how does the 4.7 keep up with 25HP-55LB/ft of handicap? It lacks the loss of a torque converter and the drag of the automatic transmission. By the time it gets to the rear wheel, the 4.7s dyno at 204HP, and the 5.9s dyno at 207. A 31HP loss vs. 53. This is the primary reason why manuals are typically faster. Not shift speed.

 

[Demon-Xanth]

Originally posted by: notfred
The fastest cars in the world in the 1/4 mile are all automatic.

The fastest cars in the world in the 1/4 mile have no transmission. Just a centrifugal clutch assembly that has 7 disks and has been known to glow red hot after burning up all the disks in the 4.5 seconds it took to go 1320 feet.

 

[desertdweller]

I think people responding should qualify thier response with how much experience they
have had in the driver's seat.

I've raced both.

Auto is far more consistent and generally faster. But, you must put some work into it, shift kit,
stall converter, etc.. Manual is more fun.

Racing aside, I don't like having to take my arm off my woman to shift.


DD

 

[Jeff7181]

Originally posted by: notfred
The fastest cars in the world in the 1/4 mile are all automatic.

If you're talking about Top Fuel, no, they're not automatic... they're direct drive. There's one forward and one reverse gear. The innards look more like an automatic than a manual. They use clutch packs that looks almost exactly like the frictions and steels in an auto. The clutch slips more than half the way down the track... it's controlled pneumatically (I believe) and centrifugally. As output shaft speed increases, clutch pressure increases, eventually to the point where it's locked and they're getting 1:1 input/output ratio.

 

[Nyical]

If it's a 1/4 mile,I would thing automatic

If it's Rally/Cross Country I would think it would be Manual.

 

[Jeff7181]

I think people responding should qualify thier response with how much experience they have had in the driver's seat

I drove my high school teacher's 79 cobra that had a C6 probably... 3 or 4 times. Drove my cousin's 69 Malibu with a TH400 at least 20 times. Drove my friend's 86 Mustang with a T5 4 or 5 times maybe. Drove my neighbor's 92 S-10 with a T5 once. And both of my 1977 Cutlasses had TH350's.

the 79 and 69 were track only cars... the rest were either daily drivers or at least streetable.

 

[Ryan]

Originally posted by: yayo

Originally posted by: Eli Depends on the driver.. but I think manuals tend to be a bit faster, all else being equal.

and the make of the car. I've seen some ricers get dusted by Buicks before.

That has nothing to do with this discussion, you're compairing two different cars.

 

[Whisper]

Yep, someone finally cleared up what I'd heard: why autos are faster in the 1/4 mile than manual.

Then again, I don't know if we'll be seeing autos replacing manuals when turning is concerned anytime soon. Computers can't yet see the road ahead, after all.

However, like someone else mentioned, the original question is a bit flawed. You really should state whether you mean the typical autos that come with production cars, or something a bit more race-oriented.

 

[Scarpozzi]

Of course, the fastest is a jet engine...and you have to "Manually" turn on the engine.

 

[Jeff7181]

Originally posted by: Scarpozzi
Of course, the fastest is a jet engine...and you have to "Manually" turn on the engine.

Actually Top Fuel dragsters are faster than the jet powered cars... jet powered cars get off to a slow start, but they can accelerate forever... it just takes more than 1/4 mile for their top end acceleration to overcome the low end acceleration of a Top Fuel car.

 

[Demon-Xanth]

Some food for thought regarding top fuel dragsters:
Thier engines turn about 540 times during the length of a run.

 

[Informant X]

In the 1/4 mile is it even possible to launch nearly ass good in a auto as you can in a manual? In a manual you can just pop off the clutch and hook, but you can't do that in auto right?

 

[Maverick]

depends on the car and the driver...some manuals are better than their auto counter parts...and vice versa.
But manual is always more fun

 

[notfred]

Originally posted by: Informant X
In the 1/4 mile is it even possible to launch nearly ass good in a auto as you can in a manual? In a manual you can just pop off the clutch and hook, but you can't do that in auto right?

haha, you've never actually driven a car in a 1/4 mile race, have you?

 

[Jeff7181]

Originally posted by: Informant X
In the 1/4 mile is it even possible to launch nearly ass good in a auto as you can in a manual? In a manual you can just pop off the clutch and hook, but you can't do that in auto right?

Yes, if you use a transbrake... what that does is basically put the transmission in 1st and reverse gear at the same time, so you don't have to hold the brake, and bring the converter to it's stall speed. When you release the trans brake, it takes it out of reverse... and there's no slippage at all inside the transmission, or in the converter per say, since it's already slipping as much as possible. So in reality, launching with an automatic transmission equipped with a transbrake is actually better than with a manual.

(the 69 malibu I drove on several occasions was equipped with a transbrake, and was one hell of a launch) and BTW... it's not as simple as just dropping the clutch and hook =) when you have an engine making any kind of power, dropping the clutch will usually send the tires up in smoke... unless you've got a set of slicks that are too big for your application =)

 

[Gyrene]

I find it insanely hard to launch my car (480whp) now that it has a lightened flywheel. I had traction problems before, but now they're just insane. It's points like these where I wish I had an automatic.

 

[Jeff7181]

Originally posted by: dtyn
I find it insanely hard to launch my car (480whp) now that it has a lightened flywheel. I had traction problems before, but now they're just insane. It's points like these where I wish I had an automatic.

Funny how people do things to try to improve performance, and it has an effect they don't plan on, and it actually reduces their times =) Out of curiosity, what engine?

 

[LAUST]

Originally posted by: Jeff7181

Originally posted by: notfred
The fastest cars in the world in the 1/4 mile are all automatic.

If you're talking about Top Fuel, no, they're not automatic... they're direct drive. There's one forward and one reverse gear. The innards look more like an automatic than a manual. They use clutch packs that looks almost exactly like the frictions and steels in an auto. The clutch slips more than half the way down the track... it's controlled pneumatically (I believe) and centrifugally. As output shaft speed increases, clutch pressure increases, eventually to the point where it's locked and they're getting 1:1 input/output ratio.

Top fuel is a rail, not a car IMHO

 

[Jeff7181]

Top fuel is a rail, not a car

Car -

1.) An automobile.
2.) A vehicle, such as a streetcar, that runs on rails: a railroad car.
3.) A boxlike enclosure for passengers and freight on a conveyance: an elevator car.
4.) The part of a balloon or airship that carries people and cargo.

*EDIT*

And I should ad...

Automotbile -

1.) A self-propelled passenger vehicle that usually has four wheels and an internal-combustion engine, used for land transport. Also called motorcar.

 

[Demon-Xanth]

Autos are stupid easy to launch compared to manuals. That's what actually gives them an advantage in adverse conditions. A super street (iirc that was the name of the class, the cars were "potentially almost streetable but not really") event was filled with guys that had manuals and one guy had an auto. The weather was unusually hot. The guy with the auto took the top qualifying spot because of the conditions. The guys with the clutches were just going up in smoke. In better track conditions, where the manual drivers could've hooked it up quite a bit better and would have had an advantage.

And the "drop the clutch and go" makes for low overcast and not much movement even in my tame vehicle.

 

[LAUST]

Originally posted by: dtyn
I find it insanely hard to launch my car (480whp) now that it has a lightened flywheel. I had traction problems before, but now they're just insane. It's points like these where I wish I had an automatic.

My traction isn't that great either... thankfully I have a transfercase (all my times are in 4x4)

I really need to get down to Sealevel and run it though.. ignorant people see 14.9 @ 5800ft alt and they think, oh well it's a 14.9

Sure is fun when I'm going down the road at 45mph and I punch it and my 285X70-R16 Yok's break loose though

Very happy owner of a 4L60-E BTW

 

[Maverick]

Originally posted by: LAUST

I really need to get down to Sealevel and run it though.. ignorant people see 14.9 @ 5800ft alt and they think, oh well it's a 14.9

I hear that...Denver's altitude kills my car as well...hoping I'll get to try it at sea level soon.

 

[LAUST]

Delete

 

[Shantanu]

With automatics you always get the same performance, regardless of whose driving. But with manuals, it varies depending upon the skill of the driver.

With a professional driver, though, the manual transmission will almost always be faster than the automatic.

But the degree to which it is faster depends upon the quality of the automatic transmission. The Cadillac CTS, for example, has a really efficient automatic transmission, so it's 0-60 times for automatic are about the same as a manual being driven by a professional driver.