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koncise
01-28-2004, 04:05 AM
I got into this big discussion with a friend who claims that an auto would beat a manual in the 1/4 mile? assuming both cars are equally powered... what do u all think?

funny thing is, i drive auto, he drives manual.

but anyway... input please

anc325
01-28-2004, 04:06 AM
you will loose every time....

manual is faster

SickFinga
01-28-2004, 04:10 AM
No way in 1/4 mile.
but i think auto is usually geared better for highspeed runs
like 150km/h+ runs. I dunno really
but no way auto is faster.
With manual you can launch you car at the certain RPMs where you car got most torque. You cant do this with auto.
But then again, new blown benz's got their peak torque at ~2000 RPMs, you can reach it with brakestand.

koncise
01-28-2004, 04:15 AM
thanks for the replies

just to be clear.. lets assume its the EXACT same 2 cars, and both are completely STOCK. And they also got the best launches they're capable of :)

SickFinga
01-28-2004, 04:20 AM
Originally posted by koncise
thanks for the replies

just to be clear.. lets assume its the EXACT same 2 cars, and both are completely STOCK. And they also got the best launches they're capable of :)
if they are EXACT same cars, they should be exactly the same ;)

but if you mean both 325i but one is auto another is 5 spd stick.
5spd will win the race

koncise
01-28-2004, 04:22 AM
Originally posted by SickFinga
if they are EXACT same cars, they should be exactly the same ;)

but if you mean both 325i but one is auto another is 5 spd stick.
5spd will win the race

haha, jackass :P yea, i meant same except the tranny :)

SCNISTER
01-28-2004, 04:52 AM
Let's clear up a few things here. :)

Not all cars are the same. To say that in every case a manual would win simply isn't true. If that was the case, then why aren't all pro-street dragsters manual? The truth is, almost all are auto.

Maybe in the BMW circles, the 5 speeds are faster. I'm not too familar with the trannys in your cars and how they work so excuse my ignorance.

In my case, I have a Thunderbird SC. It's an auto. The auto's run faster than the 5 speeds every time. Same goes for a friend with a Camaro Z28, the auto is superior on the track(better launches) but the 6 speed is lethal on the highway.

koncise, I've raced you before and I can tell by the way your car launches that the setup and how the car launches is very different from how a Ford or Chevy would. It goes to show that in the case of the BMW's, the manuals may be superior, but in many other cases, the auto's take the cake. *th-up*

85eta
01-28-2004, 05:01 AM
manuals are quicker than auto's in my experience for two reasons.

1) manuals can be shifted faster than auto's
2) manual cars are lighter than auto's

SCNISTER
01-28-2004, 05:07 AM
Originally posted by 85eta
manuals are quicker than auto's in my experience for two reasons.

1) manuals can be shifted faster than auto's
2) manual cars are lighter than auto's

No offence, but your experience must be limited.

A human cannot shift faster or more accurate than a computer. Maybe a stock auto isn't as quick as some people can shift manuals, but if you put a shift kit into a auto, the shifts are harder, more crisp and consistant.

Why would a manual be lighter than an auto? :confused:

SebSter
01-28-2004, 05:11 AM
isnt it also that more power actually gets to the wheels through a standard tranny than through an auto?

thinair
01-28-2004, 05:14 AM
Originally posted by SCNISTER
No offence, but your experience must be limited.

A human cannot shift faster or more accurate than a computer. Maybe a stock auto isn't as quick as some people can shift manuals, but if you put a shift kit into a auto, the shifts are harder, more crisp and consistant.

Why would a manual be lighter than an auto? :confused:

Actually, 90% of the automatic transmissions don't shift all that fast. Manual transmissions also soak up a lot less power then auto's (driveline losses).

I could probably shift faster then a lot of automatics, both up and down, you just have to know how to do it. Most automatics are setup to be pretty tame, the engineers don't want you to get whiplash when the tranny shifts.

Manual transmissions are faster. If they weren't you'd see all racers using slushboxes instead of manuals.

Even the clutch pedal-less paddle shifters of F1 and such have clutches (no torque converters) as to not weigh down the cars and suck power from the engine.

Get two identical cars for example, the 325i's previously mentioned (yes, one auto and one manual), dyno them, you'd think they'd have the same rwhp, but the manual always has more.

SCNISTER
01-28-2004, 05:15 AM
Originally posted by SebSter
isnt it also that more power actually gets to the wheels through a standard tranny than through an auto?

True, there's a slight loss in the torque converter.

Simby
01-28-2004, 05:16 AM
Hmm, this is a interesting thread. I can only drive auto but I never knew it could be faster than stick. More info!

SCNISTER
01-28-2004, 05:39 AM
Originally posted by thinair
Actually, 90% of the automatic transmissions don't shift all that fast. Manual transmissions also soak up a lot less power then auto's (driveline losses).

I could probably shift faster then a lot of automatics, both up and down, you just have to know how to do it. Most automatics are setup to be pretty tame, the engineers don't want you to get whiplash when the tranny shifts.

Manual transmissions are faster. If they weren't you'd see all racers using slushboxes instead of manuals.

Even the clutch pedal-less paddle shifters of F1 and such have clutches (no torque converters) as to not weigh down the cars and suck power from the engine.

Get two identical cars for example, the 325i's previously mentioned (yes, one auto and one manual), dyno them, you'd think they'd have the same rwhp, but the manual always has more.

Yea, most auto's are tame, but $275 and you have a shift kit that chirps through gears as good as you could manually.

If manual transmissions are faster, then why don't all race cars use them? The majority of drag cars are auto's. Auto's are better for the strip and manual is better for solo type road racing.

You cannot really say a manual is "faster" as it's not the tranny doing the work, it's the driver. It's all on the driver to make a strong shift.

In regards to the dyno numbers, the difference between auto and manual is minimal, +-5hp at best.

I've seen both sides of the table. I've owned a 5 speed, two in fact and a few auto's and well. I've driven both an auto with and without a shift kit. The auto with the shift kit is simply superior on the track.

thinair
01-28-2004, 05:56 AM
Originally posted by SCNISTER
If manual transmissions are faster, then why don't all race cars use them? The majority of drag cars are auto's. Auto's are better for the strip and manual is better for solo type road racing.

Drag racing is a different story, especially when you're talking about high strung multi thousand horsepower engines. You'd need a huge multidisk clutch setup and and extremely strong left leg if you want to work that clutch.

Drag cars use them more for practicality then anything else. Who wants to replace their clutch everytime they hit the track? (On very high horsepower engines)

SCNISTER
01-28-2004, 06:06 AM
Originally posted by thinair
Drag racing is a different story, especially when you're talking about high strung multi thousand horsepower engines. You'd need a huge multidisk clutch setup and and extremely strong left leg if you want to work that clutch.

Drag cars use them more for practicality then anything else. Who wants to replace their clutch everytime they hit the track? (On very high horsepower engines)

Considering most high HP engines require some type of rebuild after a race, a clutch replacement wouldn't be the issue that turns them off. If a manual box was truly the best, they'd use it despite the cost on all dragsters.

They use them for their consistancy and for their amazing launches. Nothing beats a wheels up launch with a high stall converter! *th-up*

thinair
01-28-2004, 06:16 AM
Originally posted by SCNISTER
Considering most high HP engines require some type of rebuild after a race, a clutch replacement wouldn't be the issue that turns them off. If a manual box was truly the best, they'd use it despite the cost on all dragsters.

They use them for their consistancy and for their amazing launches. Nothing beats a wheels up launch with a high stall converter! *th-up*

That is what I was trying to say, a clutch setup would slip, the 6000hp that your average top fuel dragster has is a lot of horsepower, and for it not to slip no one could physically use the clutch, or if they could, not fast enough to be competitive. And once heat takes over the clutch assembly, there would be no consistancy.

But for 'low' horsepower, say 600hp or less, I'd still go manual, but that's just me. It really depends a lot on the car too. If you're in a domestic drag car you're more then likely going to be using an auto tranny with a shift kit and high stall converter. But if you're in an import (excluding mercedes), you're more then likely going to sporting a manual which a heavy duty clutch kit. How many high horsepower drag Porsches, Supras, Skylines, etc do you see with automatics right?

For 'normal' performance street driving, I'll take my manual.

In the end it's personal opinion.

SickFinga
01-28-2004, 06:24 AM
You sure dragsters use automatic, not sequential gearboxes?


Cause i see them shift up.

SCNISTER
01-28-2004, 07:06 AM
Originally posted by thinair
That is what I was trying to say, a clutch setup would slip, the 6000hp that your average top fuel dragster has is a lot of horsepower, and for it not to slip no one could physically use the clutch, or if they could, not fast enough to be competitive. And once heat takes over the clutch assembly, there would be no consistancy.

But for 'low' horsepower, say 600hp or less, I'd still go manual, but that's just me. It really depends a lot on the car too. If you're in a domestic drag car you're more then likely going to be using an auto tranny with a shift kit and high stall converter. But if you're in an import (excluding mercedes), you're more then likely going to sporting a manual which a heavy duty clutch kit. How many high horsepower drag Porsches, Supras, Skylines, etc do you see with automatics right?

For 'normal' performance street driving, I'll take my manual.

In the end it's personal opinion.

With my next car, I'm most likely going with the 6 speed option. I don't spend enough time at the track to warrant a built auto, but would rather prefer the grunt of the 6 speed on city streets and highways :)

When I refer to "dragster" I'm not referring to all "dragsters". I'm more reffering to drag racing in general and that the tranny of choice tends to be the slushbox.

blacknblue-e30
01-28-2004, 07:39 AM
if both the manuel and auto are the same power

there is no chance for the auto to beat the manuel

unless ofcourse the manuel driver misses every shift, that includes stalling it at the line :)

M3ti Compact
01-28-2004, 01:08 PM
With the high HP engines, the revs will go up so fast that an automatic will handle the power much better than an manual, and they have so much power, that the torque converter loss is chumps change.

But for a street car, with OEM trans, for sure manual is faster than automatic. This is especially more evident in engines with small displacement. In my owners manual, it shows that the manual trans 318ti is a second faster than the automatic 318ti from 0-60.

chromius
01-28-2004, 02:46 PM
In a street car a Manual would definitly win out over an Auto....Tourque converters are just not efficient enough and drivetrain loss is a definit issue, even if it is only 5-7 hp loss, that could make or break the race. but not only that, with a manual you can push the car a little harder ie. into the red a little. You can shift when you want, and it gives that little edge.

Also there is no comparison if we are talking about a road course with turns, cuz then the manual really shows its stuff, being able to downshift before a turn and being in the right gear comming out of a turn makes all the difference in the world.

moerom
01-28-2004, 03:41 PM
Here's the deal:

1.) Stock situation (assuming both cars are otherwise identical)

- manual has less coefficient of mechanical drag
- auto car tends to be about 100lbs heavier
- you can shift faster in a manual than an identical car in automatic, because factory automatic shift programs are all very soft
- even though sometimes autos have a higher final drive ratio, it is used due to the extra weight the car has to carry, as well as the imprecise (relative to a manual tranny) dynamics of a torque converter
- all the above holds true ONLY WHEN the driver w/ the manual tranny drives correctly

2.) Modified

A modified automatic tranny will always shift faster, harder, and more predictably than a manual tranny, and plus, it has no margin of error. There are more frictional losses, but the lack of error due to mishifts more than makes up for that. Many high HP drag racers use automatics for this very reason.

Unknown
01-28-2004, 04:22 PM
Read car magazines and look at the weight of the cars, manual is lighter, and the times are faster (ex. 0-60: 5.3sec, manual...5.5 sec auto)

Yes it is only 2 tenths of a second, but it is still faster.

Besides, manuals are more fun, you can't control a drift very easily with auto can you? Although a buddy drifts his mom's GS300 pretty well...

WhadUpp
01-28-2004, 04:35 PM
Originally posted by SickFinga



Cause i see them shift up. [/B]

Maybe 2 speed ?:confused:

Jon@Bimmersport
01-28-2004, 04:48 PM
doesnt auto take more power away so less power to the ground? stockl 95 M3 auto puts 177 to the wheels, stock 95 5spd puts 199....i saw it on the dynos from AA website..

nseverin
01-28-2004, 05:30 PM
auto differentials are geared different than manuals so it depends on the car.
and #2 IT TAKES POWER FROM THE ENGINE TO MAKE AN AUTOMATIC SHIFT. YOU DON'T GET SOMETHING FOR NOTHING!
MANUAL IS THE TRUE FEELING OF CAR. DON'T BE LAZY:cool:

Cosmic 325i
01-28-2004, 07:34 PM
in my manual from bmw the exact same cars (one auto and one stick), the manaul was 1 second fastre than the auto 1.4 mile ...according to BMW

Mystikal
01-28-2004, 08:10 PM
No factory-produced car is faster with an automatic. The most extreme car built with both trannys would be the 911TT, and it is significantly faster with the standard gearbox.

I have read, repeatedly, that the reason auto's are used in drag applications is more for consistency than any other reason. It takes the human error factor out, and allows the designers one less variable in the way of tuning.

The bullshit stops here.

E30ZeRo
01-28-2004, 09:50 PM
sometimes car designers have to "detune" the engines on auto trannies to make the car's emissions pass. on the new rx-8s, the designers had to "detune" the engine 40 hp to pass emissions...
so yay for manuals......along with the fact manuals are more fun to drive. *th-up*

ImolaMZ3
01-28-2004, 10:10 PM
This is one interesting post. For once most of the information is accurate!

To answer the question, as said previously, in stock for the manual will be faster. Up to a second in some vehicles. A modified automatic will be consistantly faster. Out of ten runs the manual may get one or two faster et's but the automatic will get more. In out and out drag racing that is what counts. On the street the guy driving the automatic will not very likely make a mistake. The twisties are another subject. Even a good manu-matic has delay built in and this is a killer when trying to drive fast. Some of the newer trannies, SMG, have this solved and will become the predominent transmission over the next decade. Why? All around faster with no mistakes. Ask all those S54 owners who have missed a shift. Car makers will stick make manuals for those who love Ultimate Control, me included. Just beware of the guy beside you in the automatic Mustang with a shift kit. He won't miss his shift.

BladeRunner
01-29-2004, 02:39 AM
I would say acceleration depends on the driver, tranny and car. If the driver knows what gear and what engine speed to hit before a shift than the manual will win. Think about a manual tranny allows the driver to feed the desired amount of power, but shifing speed and time plays a factor.

The autos, well some autos, have smoother acceleration and if i remimber correctly are their shifts are computer controled so the tranny may shift to the next gear once the power curve starts dropping. However, many people say auto waste power rathe than produce or handle power like the manual...

Simply put, I say driver, tranny and car make decide the acceleration.

Mohamed 525i
01-29-2004, 08:31 AM
well, as per my knowledge the diffrence might be with the diff. coz each car has diffrenet ratio between auto and manual coz I had before two cars 320 on auto and other is manual both with filter and plugs and so ( model 89 ) I noticed the diffrence so I checked the car the diff. ratio is diffrenet in both cars,, and the manual is the winner with me always

omid
01-29-2004, 03:31 PM
stick would win for sure

Gianpaolo_E46
01-29-2004, 11:55 PM
can some one tell me why a manual car has better fuel economy over an automatic? espically since in most manuals the rev's seem to be higher for normal shifts

thinair
01-30-2004, 12:30 AM
Originally posted by T_DOT_BIMMER
can some one tell me why a manual car has better fuel economy over an automatic? espically since in most manuals the rev's seem to be higher for normal shifts

Less frictional losses, and lower revs isn't the only thing that increases efficiency. If that was the case everyone would be cruising around in 5th gear at 40km/h, but then the engine load would be high that you'd probably waste more gas then if you were going 80km/h.

SickFinga
01-30-2004, 12:42 AM
hmmm you all stuck on one thing SHIFTING.
But you all forgetting that with stick you can launch at higher RPMs and shift at appropriate RPMs.

Also not sure but how automatic can shift faster?

automatic shift smooth all the time, with manual you can just drop the clutch.

Also DINAN got software for the slushbox, still it wont make auto faster than stick.