Automatic vs Manual

[6 Wheel]

Originally Posted by strokin'_tatsch

the biggest advantage to an auto is the ability to spool on the line. in a manual trans you cannot spool up the turbo before launching

Who says you cant do a boosted launch in a manual? i beg to differ

[Charles]

Manual trans people just don't understand...


I enjoy driving a crisp manual, and I can shift as fast as the next guy, usually faster... but I'm smart enough to understand what's going on with a manual trans as well.

First off... with a manual trans, no matter if the shift takes 1 second, or 1 microsecond, the engine and the drive wheels WILL be disconnected on EACH and EVERY shift. Period. You CANNOT be in one gear as you apply the next. One gear MUST be disengaged before the next can be engaged. Under high power this leads to a LOT of driveline shock. Aside from putting undue stress on the driveline it puts undue stress on your ability to maintain traction... something that becomes more and more critical as power goes up.

Second problem with a manual. Each and every time you shift brutally fast, although still slower than an auto shift, you are murdering the syncros. Because the weight of the clutch required to hold a decent engine producing 1000+ ft/lbs of torque is going to be HEAVY, in comparison to a lighter clutch designed to hold say 500ft/lbs. Dual disc???? Forget it..... You might as well plan on sticking it in gear and leaving it, or including transmission R&R in with your routine oil change intervals... It's a catch 22. If you run a single disc, it's lightweight, and will shift decently (although much slower than an auto, even if your name happens to be Jesus) but it won't hold sh*t. And if it's a multidisc, it'll hold great, but the disc weight makes syncronizing a formidable task, and lightening quick shifts come at the cost of SERIOUS syncro and collar wear. All the while making comparitively grandma shifts next to an auto trans.

Third problem... You can't launch. Okay sure..... lets say you have a line lock, and you start in 3rd gear and slide the clutch out to make the pass. You really think this compares to a centrifugal slider or a torque converter??? Please... Next, because of that whole disengage/engage thing on each and every shift, as opposed to an auto that GAINS boost on each shift, the manual loses it. Maybe not much, maybe you don't even notice, but it damn sure doesn't jump UP a few psi does it?



Basically, manual transmissions are for tow trucks. And even that is debatable.... but I can at least see the appeal.

For hauling ass, there is no debate. RWHP for RWHP the auto wins. As vehicle power gets lower and lower approaching stock, then the manual seems like a capable trans. Simply because the parasitic loss is a bit less, and at pathetic power levels, everything is happening so slowly, and the loads on vs off the power between gears are miniscule. But you start dealing with a vehicle that's unloading the front suspension on power and a manual just starts losing ground hand over fist.

The manual trans lost it's place in this world when the lockup torque converter went mainstream.


Lastly....

There's a repeating theme of manual trans guys talking about choosing the shifts and such. Do you guys not understand what a full-manual auto is???

You act like you're totally oblivious to the ability to CHOOSE EXACTLY when and where you make FULL THROTTLE shifts with a full-manual auto.

And gassers and diesels suffer the same fate. Gasser manual cars lose to auto cars every day just the same. Except as stated above, when the power is pitiful and the bit of extra loss through the auto breaks the deal. Which hopefully isn't a valid scenario for anyone on this site....


Full manual auto FTW.


(Coming from a manual guy that swapped to a full-manual auto after exhausting all options on keeping the manual alive in a DD)

[jaybuller]

How much money are we talking about putting in the best, most reliable, able to hold the most power auto tranny? I know for fords they have the the bts 4r100, for under 5k. How about for behind a 12v?

[Hurley]

A well built 47rh? Gotta pay to play, and the big boys are paying their dues too.

I'm beginning to like Charles' posting habits

[Charles]

Originally Posted by jaybuller

How much money are we talking about putting in the best, most reliable, able to hold the most power auto tranny? I know for fords they have the the bts 4r100, for under 5k. How about for behind a 12v?

What does the engine matter? If people stick 12 valves into Fords in front of a 4R then you could stick a 4R in a dodge behind a 12v just the same. Or just get a nice, cheap full-manual valvebody for the dodge trans and a gate type, or ratchet shifter.

I think I payed 2800 for my BTS. And had already bought a replacement ZF6 for 2000 dollars before that. Which was a STEAL. So, I guess we're talking about 800 bucks more for the auto? Fwiw, I had broken the second ZF6 when I went to the 4R. So it's not like the ZF was some kind of masterpiece.

The next expense for each is a clutch vs a converter. Considering that the only clutch that will hold 600+ is a dual disc, you're looking at ~1400 or so. Whereas I gave 800 for my converter. I think the going rate is ~1000 any day of the week.

Only additional expense I had was the controller, since I wanted full-manual. For full-manual I had to give another 600.

All in all, I really don't see how there's even a comparison to be made.

[displacedtexan]

Charles, you can get a DD for a grand... Other than that I agree with everything you said.

I do prefer a manual, I like working the clutch. But I have 400/1000 and don't race... It's one of my faults

[jaybuller]

I was just wandering on the price so I could see if I could afford it..... anyone think a 4r100 bts, would hold up too drag racing and sled pulling behind a 750hp 12v?

[displacedtexan]

If you can afford to build, race, and pull a 750hp truck the tranny isn't going to save you a significant amount of money either way.

And if a few hundred dollars is the difference in affording it or not can you really afford the truck and breakage that WILL happen?

[jaybuller]

Originally Posted by displacedtexan

If you can afford to build, race, and pull a 750hp truck the tranny isn't going to save you a significant amount of money either way.

And if a few hundred dollars is the difference in affording it or not can you really afford the truck and breakage that WILL happen?

A few hundred? I see some folks claiming to have spent over 7k on dodge trannys... I can afford to build it now keep building over and over prolly not....

[displacedtexan]

Then ask tony597fitter about his NV4500 adventures

Racing is MURDER on a truck manual.

And if you are gonna race and pull it, stuff will break.

[hummin cummins]

Originally Posted by Charles

Manual trans people just don't understand...


I enjoy driving a crisp manual, and I can shift as fast as the next guy, usually faster... but I'm smart enough to understand what's going on with a manual trans as well.

First off... with a manual trans, no matter if the shift takes 1 second, or 1 microsecond, the engine and the drive wheels WILL be disconnected on EACH and EVERY shift. Period. You CANNOT be in one gear as you apply the next. One gear MUST be disengaged before the next can be engaged. Under high power this leads to a LOT of driveline shock. Aside from putting undue stress on the driveline it puts undue stress on your ability to maintain traction... something that becomes more and more critical as power goes up.

Second problem with a manual. Each and every time you shift brutally fast, although still slower than an auto shift, you are murdering the syncros. Because the weight of the clutch required to hold a decent engine producing 1000+ ft/lbs of torque is going to be HEAVY, in comparison to a lighter clutch designed to hold say 500ft/lbs. Dual disc???? Forget it..... You might as well plan on sticking it in gear and leaving it, or including transmission R&R in with your routine oil change intervals... It's a catch 22. If you run a single disc, it's lightweight, and will shift decently (although much slower than an auto, even if your name happens to be Jesus) but it won't hold sh*t. And if it's a multidisc, it'll hold great, but the disc weight makes syncronizing a formidable task, and lightening quick shifts come at the cost of SERIOUS syncro and collar wear. All the while making comparitively grandma shifts next to an auto trans.

Third problem... You can't launch. Okay sure..... lets say you have a line lock, and you start in 3rd gear and slide the clutch out to make the pass. You really think this compares to a centrifugal slider or a torque converter??? Please... Next, because of that whole disengage/engage thing on each and every shift, as opposed to an auto that GAINS boost on each shift, the manual loses it. Maybe not much, maybe you don't even notice, but it damn sure doesn't jump UP a few psi does it?



Basically, manual transmissions are for tow trucks. And even that is debatable.... but I can at least see the appeal.

For hauling ass, there is no debate. RWHP for RWHP the auto wins. As vehicle power gets lower and lower approaching stock, then the manual seems like a capable trans. Simply because the parasitic loss is a bit less, and at pathetic power levels, everything is happening so slowly, and the loads on vs off the power between gears are miniscule. But you start dealing with a vehicle that's unloading the front suspension on power and a manual just starts losing ground hand over fist.

The manual trans lost it's place in this world when the lockup torque converter went mainstream.


Lastly....

There's a repeating theme of manual trans guys talking about choosing the shifts and such. Do you guys not understand what a full-manual auto is???

You act like you're totally oblivious to the ability to CHOOSE EXACTLY when and where you make FULL THROTTLE shifts with a full-manual auto.

And gassers and diesels suffer the same fate. Gasser manual cars lose to auto cars every day just the same. Except as stated above, when the power is pitiful and the bit of extra loss through the auto breaks the deal. Which hopefully isn't a valid scenario for anyone on this site....


Full manual auto FTW.


(Coming from a manual guy that swapped to a full-manual auto after exhausting all options on keeping the manual alive in a DD)

Charles, enlighten me on what to do if an auto will NOT hold up behind a 12v.Not even for one 1/8 mile pass.

[mondtster]

Originally Posted by hummin cummins

Charles, enlighten me on what to do if an auto will NOT hold up behind a 12v.Not even for one 1/8 mile pass.

Build one that will. It doesn't necessarily have to be a torqueflite, although they're seeming to be doing just fine.

[hummin cummins]

Originally Posted by mondtster

Build one that will. It doesn't necessarily have to be a torqueflite, although they're seeming to be doing just fine.

Point me to someone who can. I have had the best transmissions and converters that are available. I have had enough of running a pass and pulling the trans. I am keeping our truck in the shop till I can find something that works and I can afford.

[97 D-Tec]

I agree with charles 100%. In drag racing being consistant not just fast is what wins races. Its not possible for one to shift everytime the same way taking the same amount of time between every shift. An automatic can do this and be faster. The only way i can see manuals being competitive is if the DSG type gearbox shows up at our doors and even thats automated. For those of you who dont know what that is:

DSG and twin-clutch transmissions - What the DSG / twin clutch transmission is - how the DSG /twin clutch transmission works

[Charles]

Originally Posted by hummin cummins

Charles, enlighten me on what to do if an auto will NOT hold up behind a 12v.Not even for one 1/8 mile pass.

Get yourself a decent auto?


Or did you forget there are vehicles in excess of 3000hp doing just fine with autos, pass after pass? Maybe run a slider in front of an auto if your setup is taking so much time in pre-stage to spool that it's murdering the converter before the tree even comes down. I believe Mr Shied has done just that with his "Danco". Slider in front of Lenco planetaries. The evil brother to the bruno drive.

On the flipside.... if I was as convinced that manuals are better as some in this thread seem to, can any of you point me toward the manual trans option you could use in something like this?

[morkable]

I run, and have been running for 3 years now, north of 1000 hp through my automatic (48RE) and other than the occasional forward clutch replacement it has been bulletproof.

I grew up on standards, and for the life of me cant understand wanting to have a manual tranny in a daily driven truck. Dont get me wrong, I love rowing through the gears on a big truck, but it wears pretty thin, pretty quick in my opinion.. Sitting at traffic lights holding in the clutch, shifting a 100 times (might be an exageration) just to get to work.. Just my opinion but in my mind the automatic was the best invention next to sliced bread

[mondtster]

Originally Posted by morkable

I run, and have been running for 3 years now, north of 1000 hp through my automatic (48RE) and other than the occasional forward clutch replacement it has been bulletproof.

Morkable, have you been having forward (rear) clutch pack or front (direct) clutch pack issues? How many clutches in the pack? Just curious is all...

Originally Posted by hummin cummins

Point me to someone who can. I have had the best transmissions and converters that are available. I have had enough of running a pass and pulling the trans. I am keeping our truck in the shop till I can find something that works and I can afford.

Charles alluded to what I was referring to.

From what I've seen, the diesel trans and converter builders and the customers seem to have a tendency to take a different approach to transmission/driveline selection and assembly than the tried and true methods used by others. Some of it I understand and some of it makes no sense to me. It might be worth looking at what other race teams are using/doing that are racing with more conventional platforms if you haven't already done that.

What trans are you running and what parts are breaking so quickly?

[morkable]

About every season I replace the forward packs. There is usally a fair bit of debris in the pan by the end of a season. I have a few extra clutches in there, billet basket etc

[zstroken]

Originally Posted by morkable

About every season I replace the forward packs. There is usally a fair bit of debris in the pan by the end of a season. I have a few extra clutches in there, billet basket etc

Few extra clutches in the forward?

[Big Blue24]

For the record, I hate my 5 speed manual and wish I had a 47rh in my daily driver 99'.

Part of my problem is the clutch is dragging so I have to grind my way into gear when I'm at a stop light. With the Valair 13" organic, it was pleasant to drive, just couldn't quite hold 499 to wheels at the drag strip. Now I wish I would have left that setup alone. Gonna have to find an auto to build and swap or fork out $$$ for a new valair 13" Organic clutch.