6speed manuel or a 6speed auto

[PlayStation3]

ok i was looking at new cars and i came across one ( rx-8 and it has a option for a 6 speed auto now what in performence terms does a manuel have or an autoo besides having more gears usally.

[2.2 Straight six]

well, if it's a 6-speed auto it has just as many gears as the manual.

usually auto are 3-speed, or they are here at least. that increases time to reach a certian speed because it has longer/taller gears.

that's why you'll often see the 0-60 time of a manual car is lower than the auto of the same car.

assuming it has the exact same gearing you may get lower acceleration times, if the gearbox makes fast gear changes. there's a good chance it will make smoother and faster shifts than someone using a manual.

a lot of it is personal prefrence, do you like driving manuals? a manual will offer a purer and more involving driving experience, but if you're sitting in traffic you may find the manual less comfortable to drive, if you're making a lot of gear changes.

for drag racing a manual is a better option, the cluth will allow revving starts and you'll be able to shift when you want. which should be within the engine's powerband.

i think that's about it.

[UncleBob]

Originally Posted by 2.2 Straight six

for drag racing a manual is a better option, the cluth will allow revving starts and you'll be able to shift when you want. which should be within the engine's powerband.

don't know about that. Most serious drag race cars are auto's.

(to original poster) its mostly an esthetic question. Modern automatics are extremely efficient and reliable. If you thoroughly enjoy using a clutch and grabbing gears, then go with a stick. But if you don't have that odd desire, then the auto will be a better choice in most situations.

[2.2 Straight six]

Originally Posted by UncleBob

don't know about that. Most serious drag race cars are auto's.

yes, but in this case we're talking about a steet car, not a fire-breathing purpose-built drag racer.

[Moppie]

Originally Posted by 2.2 Straight six

usually auto are 3-speed, or they are here at least. that increases time to reach a certian speed because it has longer/taller gears.

Its been a while since I saw a 3sp Auto.
Most went 4 speed in the 80 (incl OD).
5sp became common in the late 90s, and now there seems to be no Limit, I believe both BMW and Mercedes have a 7sp Auto in some high end cars.

The vast majority of automatics relly on a Torque Converter, which makes a fluid connection between the engine and the wheels, it works really well, except you lose response to changes in engine speed as the fluid in the TC has to be spun up to speed and that in turn has to spin the gearbox up to speed.
Works well on a big lazy V8 pushing around a family car, dosn't work so well on a high end sports car that your trying to balance on the throttle mid corner.

There are ways around the problem, like useing a Lock Up TC that locks the torque converter to the engine, but they still unlock at idle, or when stopped, or other times when its still nice to have instant throttle response. Or, the gear box modified in such away it makes hard fast changes with a high stall speed on TC, ok in a race car, not fun on the road.

[UncleBob]

Originally Posted by 2.2 Straight six

yes, but in this case we're talking about a steet car, not a fire-breathing purpose-built drag racer.

the placement of the line you draw in the sand is your own decision

[UncleBob]

Originally Posted by Moppie

There are ways around the problem, like useing a Lock Up TC that locks the torque converter to the engine, but they still unlock at idle, or when stopped, or other times when its still nice to have instant throttle response. Or, the gear box modified in such away it makes hard fast changes with a high stall speed on TC, ok in a race car, not fun on the road.

don't quote me for every single auto out there, but I believe that most of the high-number-of-gears auto's use a lot of lock up to achieve those numbers.

IE, 4 geared speeds with 3 lockup speeds, gives you the 7 "gears" etc.

[2.2 Straight six]

Originally Posted by UncleBob

the placement of the line you draw in the sand is your own decision

we're talking about a street-driven RX-8, not a Pro Mod.

[UncleBob]

Originally Posted by 2.2 Straight six

we're talking about a street-driven RX-8, not a Pro Mod.

I would quote myself again, but its already been quoted.

You don't need a 8K RPM stall to have an impressive race machine. Infact, when turbo's enter the equation, you can make them very street friendly and still make them devistating on the track. But that is another topic. The main point was, DEPENDING ON YOUR DESIGN you can very well have both....if you so desire

[2.2 Straight six]

ok, ok. i give up. you win.

[UncleBob]

yay for the home team! What did I win??

some people are so touchy....

[2.2 Straight six]

Originally Posted by UncleBob

yay for the home team! What did I win??

some people are so touchy....

you get a slap, when my plane touches down you can have it.

i'm not touchy, it's been a long night (it's 6:55am here) i haven't slept and i've spent hours working out potential earnings and trying to find the truck i want.

[GreyGoose006]

Originally Posted by UncleBob

don't quote me for every single auto out there, but I believe that most of the high-number-of-gears auto's use a lot of lock up to achieve those numbers.

IE, 4 geared speeds with 3 lockup speeds, gives you the 7 "gears" etc.

hmmm... this dosent seem right.
i'm pretty sure that when mercedes benz says it has a 7 speed transmission, it really has a transmission with 7 gears. lets not forget that F1 cars have like 8 speed tranny's

[curtis73]

If you're asking for a personal opinion, I almost always say manual. I'm a reliability kinda guy. Manuals are typically more expensive to rebuild or fix if something fails, but in general they are a simple gear-on-gear mechanical link between the engine and the ground. If they're capable of handling the torque they are darn near indestructible.

Something to consider is the shifter design and clutch design. In the case of a vehicle like an older v6 S10, they could only fit an 8" clutch, so they didn't last long. Clutches often needed replacing every 60k, but the T5 tranny itself was bulletproof at those power levels and the shifter is a direct-internal rail system that offered reliable, consistent performance. Contrast that with a Getrag 260 in a BMW. The tranny itself was bulletproof. The clutch was adequate and long-lived. Mine had 160k on the stock clutch... but the shifter was a remote stick linked to the tranny with a shift rail. To isolate noise, BMW engineered the whole thing on nylon bushings and rubber isolators. Shifter slop was a rampant problem.

Automatics are generally competent these days as far as reliability, but as they get more complicated I hate them more and more. They use electronics to make them more intuitive which seems to just make them LESS intuitive. Drive one a bunch before you buy it. In my opinion, automatics today should be carefully evaluated in a test drive before you commit to sticking with it for a long term vehicle. Manuals should be investigated for adequacy in their application. The RX8 probably has an Aisin manual, so a quick internet search will turn up some real-world tech on it.

[MagicRat]

Originally Posted by GreyGoose006

hmmm... this dosent seem right.
i'm pretty sure that when mercedes benz says it has a 7 speed transmission, it really has a transmission with 7 gears. lets not forget that F1 cars have like 8 speed tranny's

I agree; a 7 speed trans means 7 separate gears, regarless of TC lock up.

However, usually the trans will not actually use all 7 gears on normal driving. Often they start in second gear diring normal acceleration. However, the extra gears provide more flexibility and better function over a wider range of driving situations.