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Ginamatics (Gary S. if you could help answer this one)

Posted: Thu Jul 28, 2005 11:29 am
by deathknight
Well a forum member from another forum brought up the topic of automatics and how they are faster than manuals in a drag race. Here's what he had to say.

" I want to hear how it is quicker; not how its harder to make mistakes, because thats a buncha bull. If you cant go quickly with a manual, you shouldnt be racing in the first place."

Any thoughts?

Posted: Thu Jul 28, 2005 12:11 pm
by IMBoring25
I'm not Gary (And you'll have people fall on both sides of this discussion), but I'll say that, for a drag race, it takes a substantial advantage in acceleration while a conventional manual is in gear to overcome the time that there is no acceleration while it is between gears.

In most cases for a factory street car, some combination of greater engine output in the manual, lesser parasitic driveline loss, and gearing advantage will overcome that lost acceleration time. However, if you're building a serious drag car faster than any factory supercar, I would anticipate that, as shifting in the manual takes a greater proportion of your ET, the manual's advantage would erode and start to become a penalty.

Of course, for stock or near-stock cars, that does not apply. And any other type of racing is a whole 'nother kettle of fish.

Posted: Thu Jul 28, 2005 12:12 pm
by LS1Leader
All depends on the car and the gearing. Particularly for bigger engines with flatter torque curves which really only need 4 gears for the 1320, automatics can hang or stay close with manuals, and with minor mods, can beat them handily. High stall torque converters are the best first mod for automatic V8s, gears are probably second. With the new 5+ speed automatics coming out, manuals are losing even more of that initial advantage.

This argument will not hold for many smaller engines if you're comparing a 4-speed auto to a 5- or 6-speed stick. My Civic automatic lacks the pickup of a 5-speed Civic because 5 speeds gives the manual Civic much better ratios. But even then, there's a limit as to how much extra speeds will help even a smaller-engined car. IIRC, Sport Compact Car once did a tech article discussing the potential of a 7-speed manual for a Miata. Their conclusion was that you could lose time with more speeds if you have to shift so many times.

Posted: Thu Jul 28, 2005 12:24 pm
by grievre
A high-stall torque converter lets you do brake-torque launches, which you can't really do in a manual without intensely hurting your clutch.

Posted: Thu Jul 28, 2005 12:28 pm
by deathknight
Thanks for such quick responses. :D

Posted: Thu Jul 28, 2005 12:30 pm
by LS1Leader
grievre wrote:A high-stall torque converter lets you do brake-torque launches, which you can't really do in a manual without intensely hurting your clutch.


You can brake launch even without a high-stall torque converter, but you're right, it won't be as effective.

Posted: Thu Jul 28, 2005 2:04 pm
by Johnf514
I understand that this particular topic is about drag racing. However, when debating the manual vs. auto debate, one must specify if the racing is linear or rally. It's a helluva big difference.

My two cents is spent. :wink:

Posted: Fri Jul 29, 2005 1:08 pm
by GarySheehan
I don't dragrace, so I really don't know. Assuming I was the Gary S you were referring to...

Gary
Sheehan Motor Racing
http://www.teamSMR.com

Posted: Fri Jul 29, 2005 6:20 pm
by jcprov21
I always found my manual cars to be a little quicker, but remember it also depends on how you drive it, and how well you shift and clutch!

Posted: Mon Aug 15, 2005 9:38 pm
by Daywalker
I thought there were sorta like, auto-manuals used in drag racing. Like the shifter just goes straight forward and back to go through the gears and their is a computer controlled clutch. Anyone knwo what I'm talking about?

Posted: Tue Aug 16, 2005 12:37 pm
by LS1Leader
Daywalker wrote:I thought there were sorta like, auto-manuals used in drag racing. Like the shifter just goes straight forward and back to go through the gears and their is a computer controlled clutch. Anyone knwo what I'm talking about?


That sounds like a dogbox to me. I've heard of autos being banned in drag racing, not sure which groups (NHRA/IHRA) or whether it's true, though, but I could see those being used in pro competition. Street car draggers will also buy dogboxes with straight-cut teeth if they've got massive torque and power which the stock boxes won't hold up to.

Posted: Sat Oct 08, 2005 2:23 am
by Googo
LS1Leader wrote:
Daywalker wrote:I thought there were sorta like, auto-manuals used in drag racing. Like the shifter just goes straight forward and back to go through the gears and their is a computer controlled clutch. Anyone knwo what I'm talking about?


That sounds like a dogbox to me. I've heard of autos being banned in drag racing, not sure which groups (NHRA/IHRA) or whether it's true, though, but I could see those being used in pro competition. Street car draggers will also buy dogboxes with straight-cut teeth if they've got massive torque and power which the stock boxes won't hold up to.


Daywalker is referring to the semi-automatic transmissions like dsg that shifted electronically with the stick acting as an electronic input kinda like paddles to shift the gears lower when you need it to, but when you are in an all out acceleration, let the system do the shifting for you since it can consistently shift extremely fast. Kinda like a sequential shifter, but only a center position and a forward and back motion to select gears like on wheels made for games i'm guessing from the way day described it.

Posted: Tue Feb 28, 2006 11:44 pm
by Paolo300zx
aka: tiptronic i belive. you just tell the car when to shift and it does. it's basically going through the gears manually in an auto. usually the car company makes the tiptronic transmition react faster to the diver than a regula auto. Stick is still generaly the fastest :twisted: (lol)