PDA

View Full Version : What tranny should I get?



Justin_cv87
02-08-03, 08:07 PM
Im a bit confused about what type of transmission to get. I would like manual to be able to controll the car, but auto can shift faster than a manual, so a manual would lose to an auto right? Or does Shifter faster with manual work better than letting auto shift?

So is there a way to get manual to beat an auto?

thanks in advance!

Stallion
02-08-03, 09:58 PM
I think it all depends. If you're a good manual driver than you will be better off and such. And with time and practice you will get better. Automatics loose more horsepower if you're at all concerned with that. My father and I just had our heart set on a manual so we are very happy. I guess it's a personal preference. There's pros and cons to each just like everything else in this world. :)

TR

Justin_cv87
02-09-03, 03:43 PM
Automatics loose more horsepower
Ahhh, yes that was what i was looking for. i knew there was a reason why people loved manual other than having controll over when to shift and stuff. Manual is the choice for me! Thanks TR!:Steer

Stallion
02-09-03, 10:59 PM
Yup, I was reading a little article (not sure which year Vette or even which transmissions they were comparing) but the auto lost about 21 hp and the manual only lost 15 hp. So, there you go. :)

No problem, bro. Manuals all the way! :D

TR

Tom73
02-09-03, 11:09 PM
If you are going drag racing then the auto will win out over time. The auto can be more consistent times. And in drags the more consistent you can be the better.

For road racing, then it is the manual, as it can give you more control over the car in the variable conditions.

I love a manual for fun. For commuting in heavy traffic, an auto is better.

tom...

JonM
02-09-03, 11:11 PM
Sports Car = Manual ..IMHO

Stallion
02-10-03, 03:18 PM
Originally posted by JonM
Sports Car = Manual ..IMHO

I agree.

But, Tom, why would an auto win in drag racing? After all, you wouldn't be able to choose how high the RPMs go, and you would want them high, depending on the engine specs, right?

mvftw
02-10-03, 03:29 PM
IMO, all things being equal, a manaul will win. An auto will give you close to the same times, that's why bracket racers use autos. To answer the first question...MANUAL!!!

Justin_cv87
02-10-03, 04:15 PM
What about "double shifting"? i heard that can help you accelerate faster, but would that ruin the tranny?

Tom73
02-10-03, 04:54 PM
Originally posted by Justin_cv87
What about "double shifting"? i heard that can help you accelerate faster, but would that ruin the tranny?
Accelerate faster :confused No way. Double shifting, otherwise known as double clutching, slows everything down. You go from 1st to neutral, let the clutch out, rev the motor, depress the clutch, and then go from neutral to 2nd. That is a left over from the days of the unsyncro gearboxes where you had to get the gears to the same speed before engaging the gears.

Now Power Shifting is faster but can be very hard on the transmission. Just shift a full throttle with the gas on the floor without using the clutch :eek Can be very hard on everything but the gear change is quicker.

tom...

78SilvAnniv
02-10-03, 11:58 PM
I understand the the advantage of an automatic over the manual is the consistency of the shifts, enabling the driver to perform the same with each run. Improvement (and mistakes) usually are noticed in small measures, while a manual will vary all over the place, depending on the driver's skill.

As far as rpm control with an auto, you can wind out an automatic tranny through the gears by shifting it manually.
Manually put the gear shifter into 1st and let it wind out to where you feel comfortable and then smoothly push it into 2nd, winding it again and smoothly pushing it into 3rd.

Being able to control the shift points allows the driver control over the power band, getting the maximum for the minimum effort. With so little variables, this allows the driver to have consistent times and reaction times. A manual tranny...(I am terrible with manuals!)...may not be shifted at the same point every time or the driver may miss a gear, causing great variables in times.

I have a difficult time coordinating steering, accelerator, clutch and shifting. I am much better off in an automatic!
Heidi

mvftw
02-11-03, 09:23 AM
Justin_cv87, your watching to much of the movie 'Fast & the Clueless', when Vin says you should have double clutched:eek, unless your driving a Mac truck...maybe he should of said 'power shift':cool

81NMVETTE
02-11-03, 09:52 AM
I have a Friend who runs a rail and I was surprised to see that he uses an automatic .
I asked him why He said that the auto always gives the same performance allso he can adjust the the eng trany combo through the computer ie. alt. temp.humidity.track cond. he said you could never get the eame results using a manual.
I said but you loose HP right ? he said that the consistincy (sp) more than makes up for the loss of a few HP.

I like an auto I guess having a manual for all of my growing years has made me lazy lol
Earl

Justin_cv87
02-12-03, 07:36 PM
yeah, i ment power shift, but i wouldnt wanna ruin the car.

so if 2 cars were at a track, doing a 1/4 mile race, and they were the same, and the driver was pretty good at shifting, what would win? that auto or manual?

Stallion
02-12-03, 11:13 PM
I think the manual would win. :)

mvftw
02-13-03, 09:02 AM
Manual would win, man can shift faster then machine...that's why 'in the day' there was 2 Super Stock classes, one with a manual and one with a auto.

Wamp
02-13-03, 09:21 AM
With todays automatics and computers you can tune an automatic to shift at whatever RPM you want it to, Can man shift at that exact RPM every time? The answer is NO..... The manual is fun but go look at the drag racers, 9 out of 10 will be automatics. I think Manual is alot more fun, but for drag racing I would go auto with no second thoughts.

Justin_cv87
02-13-03, 06:35 PM
well, there has to be some reason why all ZR-1's are manual... it probally makes them faster, and thats what the ZR-1 is about, just speed, so why waste ZR-1's on auto when manual is faster is probally what chevy figured.

JohnZ
02-13-03, 07:57 PM
Originally posted by Justin_cv87
well, there has to be some reason why all ZR-1's are manual... it probally makes them faster, and thats what the ZR-1 is about, just speed, so why waste ZR-1's on auto when manual is faster is probally what chevy figured.

ZR-1's were manuals because that's an essential part of the "performance sports car" image; I don't think many people would have paid $31,000 extra for a package with an automatic transmission, in addition to the fact that GM didn't have an automatic in those days that would stand up to 405hp and high rpm and still stay alive through the warranty period.
:beer

WayneLBurnham
02-16-03, 06:47 AM
While they do go out occassionally, like any other device, automatics are much less maintenance prone.

Clutch changes, especially with an inexperienced manual driver, can get frequent.

As for shift abilities, just like Heidi said, you can shift automatics. I shift my automatics constantly. On the vette, I use it in place of the brake 3/4 times.

Some claim this accelerates wear, but I've never had to replace a Torqueflite, Turbo 350 or Turbo 400. (There is no true "manual" shift in an auto - even one with a full manual valve body. You are putting in a hydraulic "request" to the tranny's hydraulic "circuitry" to change the gear at the next appropriate time. No "missed" shifts or ground gears are possible since the hydraulic control system is deciding exactly when to do what.)

Automatics may weigh more - I'm not sure. They also require a heavier cooling system with the tranny cooler which is much less efficient at removing engine heat because that cooler is in front of the radiator.

Before these Gear Vendors bolt on overdrives, there were no high power overdrive auto's - as John Z was saying. I'm right now considering a built up 700-R overdrive, but I know even the best will fail much sooner than the T400 3-speed in there. The 4L80 is a monster of a tranny - bigger dimensionally and weighing something like 130 pounds more than the 700R/4L60 and I think 100 more than the T400, so it wasn't super practical for a sportscar (although that certainly would shift that weight rearward! :) )

I admit I'm a sold auto guy, but I have always had the impression if you buy a high performance manual, be prepared to get that clutch adjusted every 3-4 months and changed every 18 if you drive it reasonably hard.

For the past week I've been driving mine without power steering, requiring two hands occassionally. THAT was enough to remind me why I like autos as well!

mvftw
02-16-03, 09:15 PM
It doesn't matter todays Automatics or Yesterdays Automatics. They have Torque Converters and Torque Converters slip. It can't beat a clutch setup. Your right 9 out of 10 racers use Autos, they are bracket racers which need consistant times. I don't want to get into a pi$$ing match, but Pro Stocks & NASCAR use manuals.

WayneLBurnham
02-17-03, 06:47 PM
to adjust and frequently change those clutches, too.....

What's useful for professional race teams with quarter million dollar base cost vehicles expected to last at most 1000 miles before total rebuild, with twice that in ready spare parts sitting in the trailer/bay, is not definitive for people with vehicles they hope will go 50-100,000 miles before significant repairs (once finished.)

not that I "want to get into a pi$$ing match" or anything either... :)

The 10% a torque converter slips is nothing compared to when a clutch starts slipping....

Newer options in automatics vs. older certianly does matter - in terms of power handling, as several mentioned. It used to be the only auto that could take over 500hp for long was a Powerglide, a LENCO, and carefully maintained/"worked on" Turbo 400's and Torqueflites. There now exist 6, 8 and greater speed overdrive automatics capable of long service with over twice that power level.

The land speed freaks use these extensively. Of course these aren't as practical an example for sportscar drivers as Pro-Street and NASCAR.... :t :eyerole

P.S.: AUTOMATICS RULE!

:w :booty

mvftw
02-17-03, 08:57 PM
This is my Last Reply...I said ALL THINGS BEING EQUAL A MANUAL WOULD BEAT A AUTO, this is fact. I'm talking about pure speed. Your talking about driving for 100k miles. Yes your right, there is maintance with a manual. But for a weekend driver, manuals the way to go...Also higher resale $$$.

WayneLBurnham
02-18-03, 01:23 AM
Ah, you shouldn't swear it's your last word! This is a thread on tranny selection! There's lots of room for discussion - and I might say something you hate! :)

Poor dinosaurs :) loving to have to shift forget the big advantage in 4-speed manuals over 3 speed autos...

...and that's more gears to run through to keep in a more optimum RPM range.

That, more than any loss from slippage in the torque converter is the source of usual advantages.

"Usual" until you include in the mix 5- and 6-speed single and double overdrive manuals and 4- and 6-8 speed and even more single and double overdrive autos, some with gear splitters (not to mention lock-up torque converters.)

These can eliminate any performance-level advantages to the manuals and give greater drivability.

As far as "pure speed", you can forget that with no overdrive, in either a manual or an auto, unless you have such a low rearend or huge diameter rear wheels, you need a million HP to accelerate like a Geo Metro.

I still wonder at the overall system vs. system weight difference too. What does an M21 with clutch weigh vs. a Turbo 400 with cooler and lines and such? I suspect the auto is considerably heavier.

The 4-Speeds do bring a somewhat higher price on resale of collector, restored or survivor cars.

If my main interest was original condition C3's, I'd have to consider a 4-speed, although I think drivability would still point me to the 3 speed auto until I could uprade it to an OD auto (which is what I've done.) That may be at the root of this too - I only ever want what works best and don't care where it comes from or whether it existed as an original option even a decade after mine came out.