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Runge_Kutta
11-12-03, 01:57 AM
Has anyone here actually tried to drive a 500hp car on
suburban bonzai runs with a manual transmission? I ask
that because I wonder what it's going to be like to drive
a 500hp Z06 or even a 625hp ZL1. In Dave McLellan' recent
book, "Corvette from the Inside," he comments on driving
a 725hp Corvette (page 279). His comment was - "At the
end of a run, I had no idea what the gauges had indicated."
The point he was trying to make is that things happen fast
with big HP and they can overwhelm the driver. Traction will be
a serious problem and drivetrain trashing will also cause
problems. Male ego aside, I think there is a lot of merit
to offering 6-speed (or even 7-speed) automatic transmissions
with the 500hp and 625hp engines. These new transmissions
could easily result in faster 1/4 mile times, less drivetrain
damage, and fewer incidents of vehicle loss of control.
Most importantly, the transmission will lessen the driver
workload so that attention can be focused on keeping the
car in the lane and foreign object avoidance.

It would, however, go in the face of an entrenched attitude
that "real men don't drive automatics."

If there were automatics offered by GM with the 500hp and
625hp engines, what would you buy (assuming you could afford
the car in the first place)?

billagroom
11-12-03, 02:09 AM
I'm going with the automatic. A well set up automatic will beat a standard every time. Remember they banned automatics in F1.

Billagroom

tt-rexx
11-13-03, 09:52 AM
most six speed drivers couldn't get through 4 gears without missing a shift in a race. not to mention going up in smoke at the start unless they have 50 plus hp on me im gone before they hit third per the drivers. auto is the way to go for 1/4 mile only the very best shifters (pros) can hang with a auto with shift kit.

ROCKETBLOCK
11-13-03, 09:59 AM
My previous Corvette was an 85 with coil over suspension, 6 speed stick, lower rear end gear and over 500hp 434ci engine. I had a ball with the stick! No probleemo.:upthumbs

HOTMOTORSPORTS
11-13-03, 10:02 AM
I've been wondering what it would be like driving a 6 or 7 speed automatic with the paddles on the steering wheel. It would have to be very crisp shifts to start winning me over.

I'm a standard trans guy. The '68 I've got listed is already getting boring and I'm either going to change it to standard or trade it for a standard.

Chuck

trumperZ06
11-13-03, 12:06 PM
:D STICK SHIFT... On a road course, you need the control a stick shift provides!

;) Current automatics can be dangerous... they will down shift if floored in the midde of a turn!

I know it's dumb... but... I have had Students with C-5 autos do it!

:( Maybe new paddle-shifters that lock into each gear.. such as BMW... will work. I haven't seen that offered by the General yet!

Corvette-Pilot
11-13-03, 12:17 PM
This months Corvette Magazine has an article about a guy that built an 850 HP Z06. He is just shifting into 6th near 200MPH and can smoke the tires at triple digit speeds !!

Seems like it might be fun yet????

Just like a Ferrari (or some such car) that does 80 MPH in 1st gear does it really make any difference?? You would have to have a custom geared close ratio to make a manual useful.

No matter how you look at it, it is like asking which of your 2 kids you like better !

HOTMOTORSPORTS
11-13-03, 12:20 PM
trumperZ06:

That's not dumb. It happened to my son last year. He was right behind me in my '97 C5 AT (the only C5 AT I've owned). He did just that expecting to come out of the corner but instead spun out. He was OK and so was the car. He was shaking from both the fact he almost got hurt and he almost damaged his dad's car. He was shocked when I told him to get back into the car but how was he to learn.

He told me he wasn't that agreesive and it took him by surprise. The automatic in a C5 is unpredictable and down right dangerous.

Chuck

Kotzenjunge
11-13-03, 01:01 PM
At least here people recognize the merits of an automatic, especially for simple cruising purposes. All of the car people I know in real life and 99% of the ones on the internet tell me automatics are useless in my GT, like it gets a weaker engine or something.

Of course, these same people also tell me that Mustangs are sports cars, so I shouldn't be listening to them anyway.

"y get an automatic in a sports car thats ghey"
"Because I don't own a sports car."
"d00d it is"
"No, it's a passenger car that happens to be powerful. The backseat disqualifies it."
"then y does my frined w/ a Cobra call his a sports car?"
"Because your friend, despite having a nice car, doesn't know how to classify it. Did you know that 90% of Corvettes, America's own sports car, are automatics?"
"w/e, d00d"

And that's that.

Vettelt193
11-13-03, 01:29 PM
Many of these manual vs. auto talks forget to mention HP loss... Quite frankly, autos put less power down to the wheels. Current autos also are missing gears... at least one, to make them more effectively put power down. When I raced an automatic car that was comparable, I would win. I also can drive stick pretty well, I am no pro, but an above average driver.

With that said, I would buy an auto if they fixed some of the problems related with them. Give me a 5+ speed auto, with the new technology that I keep hearing about (basically, a computer figures out what gear the car needs to be in, if the car is turning etc. so the car is in the right gear for road racing). If that happens, I think the auto would be faster even with the greater power loss.

On the entirely other side of the issue, if I am buying a car to drive around town and not race, I sure have fun shifting myself.... and the number one reason I bought each one of my Corvettes was FUN! so... the manual may win after all:)

HOTMOTORSPORTS
11-13-03, 01:38 PM
Kotzenjunge:

I don't understand some of your codes?

d00d ??
w/e ??

The automatic does have more loses going through the driveline as Vettelt193 stated.

I think more like 60% of the C5's are Autos.

Chuck

Vettelt193
11-13-03, 01:53 PM
Originally posted by HOTMOTORSPORTS
Kotzenjunge:

I think more like 60% of the C5's are Autos.



It is right around 70/30 auto/stick on the later C5 years, I think the early C5 years had more autos though. C4's were about 80/20 auto/stick though. I still think it is unreal how many autos there are

HOTMOTORSPORTS
11-13-03, 01:59 PM
It surprises me too. I couldn't believe it when someone told me to look that up a few years ago.

I've always had a hard time trying to sell an auto verses a stick.

Chuck

Kotzenjunge
11-13-03, 02:38 PM
Originally posted by HOTMOTORSPORTS
Kotzenjunge:

I don't understand some of your codes?

d00d ??
w/e ??

The automatic does have more loses going through the driveline as Vettelt193 stated.

I think more like 60% of the C5's are Autos.

Chuck

Of the C5s sure, but I was talking about overall. I read somewhere that 90% of the Corvettes out on the road today of all years are Automatics.

And those "codes" would be the stupid internet people, and how they talk. Since most of you are considerably older than me, I would think that you don't happen across the teenage/young adult sector of the population much on messageboards or in chats or IM. "d00d"=dude, and "w/e"=whatever.

Tom73
11-13-03, 03:02 PM
Automatics are great for everyday driving and commuting to work. A stick is more fun in the row you own thrill factor.

At a drag strip, an automatic is best. Not necessarily faster, just better in that it is more consistent. All the driver has to do is get the car off the line then set back for the ride.

On a road race course a standard is better since the driver determines when a shift happens. An automatic can down shift at an unexpected time or will not hold a gear when at a constant rpm.

So it all boils down to what the owner wants to do with the car. A commuter, a drag racer, then the automatic. A road racer, the stick. Weekend fun car, the stick. :)

No matter, whatever you get, enjoy

tom...

Runge_Kutta
11-13-03, 03:16 PM
Maybe some of you have looked over this:

http://media.gm.com/division/2004_prodinfo/tech_displays/powertrain/rwd_6speed.pdf

These transmissions are pretty fancy. As to efficiency concerns:

http://media.gm.com/division/2004_prodinfo/tech_displays/powertrain/advanced%20torque%20converter.pdf

====================================================================
Beginning in the 2005 calendar year, GM adds a Hydra-Matic automatic
transmission to the portfolio. "This will be our first production
six-speed automatic transmission for GM," said Dennis Provenzano,
Program Manager for the six-speed transmission family. Four transmission
variants are planned with three of the units designed to handle
passenger car and truck duty cycles.

The new transmission provides enhanced performance algorithm shift,
clutch-to-clutch shifting, automatic grade braking, tap up/down
operation (Driver Shift Control), an integrated center differential
for full-time all-wheel capability, and an internal control module
using micro-hybrid technology. "By having an internal transmission
controller, you're able to reduce the number of wire connections
within the transmission and external to the transmission by
approximately 50%," said Veronica Mirabitur-Spitza, Chief Engineer
for the six-speed transmission family.

http://www.sae.org/automag/techbriefs/12-2002/
====================================================================


==========================================================================
It is unlikely to see C6 but it appears that GM has been expending a
fair amount of effort on 7-speed automatic transmissions. I've
included the abstract from the most recent patent.

http://appft1.uspto.gov/netahtml/PTO/search-bool.html
==========================================================================

20030162629 (August 28, 2003)
"Family of multi-speed transmission mechanisms having three planetary gear
sets and six torque-transmitting mechanisms"
Bucknor, Norman Kenneth ; et al.

==========================================================================

20030162625 (August 28, 2003)
"Family of multi-speed transmission mechanisms having three planetary gear
sets and six torque-transmitting devices"
Raghavan, Madhusudan ; et al.

==========================================================================

20030162624 (August 28, 2003)
"Family of multi-speed planetary transmission mechanisms having four
clutches and two brakes"
Kao, Chi-Kuan ; et al.

==========================================================================

20030162623 (August 28, 2003)
Raghavan, Madhusudan ; et al.
"Family of multi-speed planetary transmission mechanisms having fixed
interconnections and six torque-transmitting mechanisms"

==========================================================================

20030130084 (July 10, 2003)
"Multi-speed transmission mechanisms with three planetary gearsets and
input clutches"
Kao, Chi-Kuan ; et al.

==========================================================================

20030060323 (March 27, 2003)
Kao, Chi-Kuan ; et al.
"Family of multi-speed power transmission mechanisms having three
planetary gear sets"

==========================================================================

20030054917 (March 20, 2003)
Raghavan, Madhusudan ; et al.
"Family of multi-speed transmission mechanisms having three planetary
gearsets and five torque-transmitting mechanisms"

==========================================================================

20030054916 (March 20, 2003)
Usoro, Patrick Benedict ; et al.
"Family of multi-speed planetary power transmission mechanisms having three
planetary gearsets"

==========================================================================

20020107104 (August 8, 2002)
Raghavan, Madhusudan ; et al.
"Multi-speed transmission family with three planetary gear sets and
five rotating torque transmitting mechanisms"
==========================================================================

HOTMOTORSPORTS
11-13-03, 04:14 PM
Runge,

Excellent material. This is the next generation auto trans. BIG torque ratings!

I wonder how long before this X_ _ R series is adapted to the transaxle setup in the C5. Kind of reminds me of the Allison 1000 and 2000 series.

Chuck