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Discussion Starter #1
Ok:
Rule Number 1: Keep it civil :D
Rule Number 2: Provide facts and/or personal observations (or at least well documented information) :thumbsup:

Soooooooo which is better, and automatic transmission (4 speed), or a manual transmission (5/6 speed)....AND why!! :rofl: :rofl:

For the following applications (in an MN12/FN10):
Drag Racing 1/4 mile
Road Racing Road course (not SCCA)
Overall Performance Highway (mpg), Drag, Road, Top end, etc.)

I’ll start off:
Drag Racing IMHO, tough call! If the car can be setup to hook properly I would say manual. But the driveline shock can often limit traction. And without a “bleed down” clutch, sometimes controlling the clutch slip will decrease consistency. As will differences in shifting from run to run. On the flipside, the automatic is a lot “nicer” to the driveline and is easier to hook up. But it is limited by the lack of gears and thus the engine won’t stay in its power band as much as a manual. But the auto can shift faster (usually) than a manual so what may be lost in gears might be gained in shift delay. (A caveat: I am not a drag racer, so for me, this answer is more opinion than fact)

Road Racing Manual: More gears will let you stay in the “power band” more than with the automatic and with the clutch you can better control the driveline shock while coming out of a curve. Whenever I lived on windy back roads, I always had better performance through the curves with a manual than with an automatic.

Overall Performance Manual: More gears, less driveline loss, more durable (if not abused), and cheaper repair/replacement. I have converted a number of cars (mainly TC’s or Mustangs) from automatic to manual and in EVERY case I (or the person I did the swap for) was very pleased with the swap.

So, thoughts, opinions, etc.
And remember rules one and two. :thumbsup:
 

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94 Daily Driven 4.6L said:
Ok:
Rule Number 1: Keep it civil :D
Rule Number 2: Provide facts and/or personal observations (or at least well documented information) :thumbsup:

Soooooooo which is better, and automatic transmission (4 speed), or a manual transmission (5/6 speed)....AND why!! :rofl: :rofl:

For the following applications (in an MN12/FN10):
Drag Racing 1/4 mile
Road Racing Road course (not SCCA)
Overall Performance Highway (mpg), Drag, Road, Top end, etc.)

I’ll start off:
Drag Racing IMHO, tough call! If the car can be setup to hook properly I would say manual. But the driveline shock can often limit traction. And without a “bleed down” clutch, sometimes controlling the clutch slip will decrease consistency. As will differences in shifting from run to run. On the flipside, the automatic is a lot “nicer” to the driveline and is easier to hook up. But it is limited by the lack of gears and thus the engine won’t stay in its power band as much as a manual. But the auto can shift faster (usually) than a manual so what may be lost in gears might be gained in shift delay. (A caveat: I am not a drag racer, so for me, this answer is more opinion than fact)

Road Racing Manual: More gears will let you stay in the “power band” more than with the automatic and with the clutch you can better control the driveline shock while coming out of a curve. Whenever I lived on windy back roads, I always had better performance through the curves with a manual than with an automatic.

Overall Performance Manual: More gears, less driveline loss, more durable (if not abused), and cheaper repair/replacement. I have converted a number of cars (mainly TC’s or Mustangs) from automatic to manual and in EVERY case I (or the person I did the swap for) was very pleased with the swap.

So, thoughts, opinions, etc.
And remember rules one and two. :thumbsup:
Well I pretty much disagree with all of that. The driveline shock at the dragstrip comment is incorrect, driveline shock is good, it works the chassis. Any traction problem caused by that is a suspension or tire problem, not a transmission issue. I highly disagree with the lack of gears and staying within the power range. If you look at a 4R70W compared to a 5 speed manual the 4R70W should actually be much better at this when calibrated properly. With the ability to lock the converter in 3 gears(or even all 4 if you use the right EEC) this gives effectively 7 forward gear ratios compared to 5. The 4 unlocked ones are variable due to the slip of the converter, allowing proper converter selection to also further contribute to staying in the proper RPM range, something a manual trans cannot do without slipping the clutch. I also disagree with the shifting faster, a purpose built drag race manual transmission also maintains constant power flow just like an automatic, there should be not even a microsecond of power not going to the wheels with either.

Road racing: see the forward gear ratio comments above, this is the same.

I don't buy the durability arguement, and certainly not the cost arguement. Cost for a quality flywheel, pressure plate, clutch, and bellhousing will far exceed the cost of a quality torque converter every single time. Again here, automatic trans calibration and converter selection is key to making them perform, and most people flat get it wrong.

There is some merit to driveline losses due to additional inertial losses and frictional losses found in an automatic. However these are greatly reduced in modern automatics compared to the older gereation ones, making this gap smaller and smaller.
 

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Discussion Starter #3
kdanner said:
Well I pretty much disagree with all of that. The driveline shock at the dragstrip comment is incorrect, driveline shock is good, it works the chassis. Any traction problem caused by that is a suspension or tire problem, not a transmission issue. I highly disagree with the lack of gears and staying within the power range. If you look at a 4R70W compared to a 5 speed manual the 4R70W should actually be much better at this when calibrated properly. With the ability to lock the converter in 3 gears(or even all 4 if you use the right EEC) this gives effectively 7 forward gear ratios compared to 5. The 4 unlocked ones are variable due to the slip of the converter, allowing proper converter selection to also further contribute to staying in the proper RPM range, something a manual trans cannot do without slipping the clutch. I also disagree with the shifting faster, a purpose built drag race manual transmission also maintains constant power flow just like an automatic, there should be not even a microsecond of power not going to the wheels with either.

Road racing: see the forward gear ratio comments above, this is the same.

I don't buy the durability arguement, and certainly not the cost arguement. Cost for a quality flywheel, pressure plate, clutch, and bellhousing will far exceed the cost of a quality torque converter every single time. Again here, automatic trans calibration and converter selection is key to making them perform, and most people flat get it wrong.

There is some merit to driveline losses due to additional inertial losses and frictional losses found in an automatic. However these are greatly reduced in modern automatics compared to the older gereation ones, making this gap smaller and smaller.
I agree with everything you said. I should have clarified the question a little bit. When I was thinking about this I was thinking more along the lines of "stock", or "slightly" modified transmissions. i.e no TC lock up in 3rd gear, no racing manuals, etc.

And I had completely forgot about the price of all the "clutch" parts. So then the durability of the clutch is also a negative.

But if we're talking about mainly "stock" applications, do you still disagree?
 

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Just thought I'd toss in my 2 cents here.

I swapped a T5 out of a 82 Mustang into my bird a year ago. Aboslutely the best thing that's ever happened to my car why Ford wouldn't give us a manual with the V8 to begin with is beyond me.

Driving my car is fantastic. Double-clutching on the downshift and stomping it coming out of the corner... wow... it's a rush. For me one of the biggest benefits is being involved in what the car is doing. With the auto you just mash the pedal and see what happens. It take some skill to operate a manual efficiently and effectively, so there is a sense of accomplishment that is an added bonus.

I agree with most of the comments made about the auto for drag racing. There is a reason that until you get up to Pro Stock level stuff they are all using a GM TH400.... A very good transmission BTW.... anyhoo, I've got to get to class....

Jimmy
 

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Auto's are definately more user friendly.
For instance aod's are crappy transmissions (everybody agree?)
Alot of people claim T5's are good transmissions(not me I hate them)
Now go to the track and watch the fox body's run. Even the guys with stock aod's have better luck at keeping them together than the guys with t5's. Yet the T5 can handle more torque. Why because missing a shift in a t5 will break it . Auto's don't break like that most of the auto issues come from overheating. Unless you are JL who broke a mechanical diode.
Don't get me wrong manual transmission have benefits. I wouldn't think about putting an A4LD in my ranger, it just doesn't have enough torque.
Auto's are more consistant than manuals for drag racing as well. On a road race scenario I would probably suggest a manual transmission for the benefit of engine braking. For overall performance I would suggest a modern lockup overdrive transmission.
Alan
 

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Discussion Starter #6
One thing I thought about as I was reading these posts is this: Why are the manual transmission cars almost always faster (i.e. 1/4 times) from the dealership (bone stock)?

For example, the Fox Mustang, the Camaro, the Vette. All the manual transmission cars are faster. Is it that the EEC tune is lower so the automatic will "live" or is it something else? :2huh:
 

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94 Daily Driven 4.6L said:
One thing I thought about as I was reading these posts is this: Why are the manual transmission cars almost always faster (i.e. 1/4 times) from the dealership (bone stock)?

For example, the Fox Mustang, the Camaro, the Vette. All the manual transmission cars are faster. Is it that the EEC tune is lower so the automatic will "live" or is it something else? :2huh:
This really relates to my comments about newer autos versus older. I think the more appropriate question is "why were" they quicker, not "why are", as the difference is almost nonexistant anymore. The new Mustang auto runs very comparably to the manual. You could say the same for LS1 cars. Put a good converter in either and the difference is pretty much nothing. Now, you might say, it isn't stock, you changed the converter. I see it different. Yes I changed the converter to get more slippage, this put me into the ideal power range quicker, much the same as slipping a manual trans clutch. If you look at what I consider to be the last bastion of real sportsman drag racing, NHRA/IHRA Stock and Superstock eliminators, invariably you'll find the auto trans combinations to be quicker than the same combination with a manual trans. Now the engine combination being the same means no appreciable power difference between 2 cars, we know the less efficient auto puts down more at the wheels, but yet the car still runs faster. Why? Two reasons pretty much. First, different trans gear ratios than stock via a custom planetary, shifting the 1st and 2nd gear ratios a good bit higher, which makes them closer ratio, allowing the engine to be operated in a narrower range due to far less RPM drop between gears. Now the manual trans cars do that too of course. But, second, proper converter selection has kept the RPMs in the ideal range for a longer time during the pass than the stick car can, thus making up for the increased parasitic loss, and then some.
 

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The only advantage useing a stick shift in one of our cars is that you no longer require a stock EEC to run the tranny, therefore can go with an aftermarket stand alone computer/fuel injection system that would make it easier to get power out of, but also highly illeagal.... :D
 

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Yeah but a manual is so much more fun to drive. And it's always in the gear you want, unlike an auto which takes a second to find the right gear.
 

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When built right, autos can be more consistent and just as fast, if not faster, than a manual, but I'd take a manual over an auto any day of the week. I like to shift my own gears, it's a lot more fun. That is good info from 94DD and kDanner by the way.
 

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94TchikinV8 said:
When built right, autos can be more consistent and just as fast, if not faster, than a manual, but I'd take a manual over an auto any day of the week. I like to shift my own gears, it's a lot more fun. That is good info from 94DD and kDanner by the way.
Amen and amen. :cool:
 

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Discussion Starter #12
94TchikinV8 said:
When built right, autos can be more consistent and just as fast, if not faster, than a manual, but I'd take a manual over an auto any day of the week. I like to shift my own gears, it's a lot more fun. That is good info from 94DD and kDanner by the way.
Agreed, and that seems to be the a reoccurring theme... the auto (when set up properly) is as fast (if not faster) than a manual... but "I'd rather have a manual". :D

Is it the “fun factor” and “being more in control” of the car (or at least feeling like you’re in control more)? I too much prefer a manual vs. an auto. Personally, my major “gripe” with an auto is the “delay” before things happen, and the spacing of the gear ratios (or the lack of gears in general). :thumbsup:

And what kdanner said about the "why are" vs. "why were" is dead on. I think now with the computer control, lock up TC's, 4/5 speed automatic transmission, the autos are right up there with the manuals. :D
 

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94 Daily Driven 4.6L said:
Personally, my major “gripe” with an auto is the “delay” before things happen
Amen to that. Whenever I stomp on it in a friendly test of acceleration, I lose a little bit of time as the thing downshifts first to 3rd then to 2nd. :rolleyes:
 

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Back in the day, around 1965-66 my buddy built a '40's Willys Coupe for the drags. He put a 401 Buick engine in it with a turbo-hydromatic not a stick. I asked him why. He said "consistency" and explained:

When the Mustang first came out, he and his brother ran down to the dealer and bought identical Mustangs. Both were 289's, both identically equipped (even the interior and exterior colors), except for the the trannies. My friend's was an auto, his brother's a stick. At the time their family owned Westhampton Drag Strip and from the time they were little kids, both brothers had spent lots of time at the track and had owned, built and raced lots of different cars over the years, so they were pretty experienced drivers. Brand new out of the box, they raced the mustangs side by side many times, even swapping drivers, and the auto beat the stick shift consistently. Now true, the stick had a stock shifter and clutch, but the auto was not modified either and had a stock converter. Neither brother could manually shift the cars as smoothly or consistently as the automatic could, and this way before the day of the EEC controlled automatic. Apparently the time lost in shifting the manual outweighed the HP advantage through the drive train. I always thought that was interesting.

By the way, the Willys did pretty well... he just couldn't keep the front wheels on the ground. He drove it on the street and used to challenge passengers to change the radio station. When they reached out to hit the pre-set he'd hit the gas and send them back into the seat. I tried and couldn't my hand within 6 inches of the dash... fun car..

You gotta be careful comparing track times published for "identical" cars with manual and auto transmissions. My automatic vette came equipped with a 2.72 rear end, I don't know off hand what rear the 6-speeds have, but I know they're lower than 2.72.

-mike
 

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My opionion:

Drag : 2 speed Chevy Powerglide
Road Racing: No Experience on this, Depends on # of turns I would say.
Highway: 5 Speed Manual (less wasted energy)
 

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transmissions

This is my personal oppinion.

1. I feel that a automatic is better for drag racing because of more consistancey
and less stress on the drivetrain. A manual can be faster if you powershift it
but most people can not and if done offten it substanialy shortens the life of
the driveline.

2. I feel in road racing a manual is perfered for a few reasons and here they are.
A automatic transmission would probly over heat from the abuse constant full
throttle runs and up and down shifts. A manual is perefered because theres is
no unexpected up or down shifts in a turn which could upset the car.

I feel over all a automatic is perefered except in lowered powered application where a 4 cilinder engine is used. The reason for this is that a automatic consumes a fair amout of power that most 4 cilinder can't afford to lose and because of the extra power consumed the fuel encomny is reduced becaue of the engine having to work harder.
 

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Yall forget a auto comes from the factory for smooth shifts (hence need for the J-mod).
So IMO to compare the two the auto needs to be spitting out as firm shifts as the manaul does.

Now compare a Electronicly shifted auto (4R or similar where you can manaully run the gears if you want) I'd say is the best all around.

And gears is no longer an issue for we now have 6speed Autos from the factory. Plus the fact of aftermarket overdrive add-ons.
 

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There's also electronic control systems for transmissions that allow you to shift at the touch of a button. But for some reason, the manual is just more fun.
 

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Gawsh, I want a Turbo 400 with a clutch :) I knew a guy had a 8-71 on a Hemi with one in his t-bucket. He coulda got by with a slipper clutch and no tranny in that thing :D
 

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SloMo228 said:
There's also electronic control systems for transmissions that allow you to shift at the touch of a button. But for some reason, the manual is just more fun.
that can be fixed....J can "modify" the 0s and 1s to do that :D

joseph
 
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