Why the auto?

[ako]

Kinda an off - topic here, but half the time when I'm flicking through these forums, I find someone mentioning about being able to out launch someone because they're auto, and the other guy isn't.. Am I just being REALLY retarded and not realising you lot are being sarcastic, or are some people serious about that? In a 500hp torque monster.. auto = good, in a sub 3L import, auto = very very bad

[seth98esT]

In an auto you just cant drop the clutch like a 5spd. Most the time these people with autos are at 140hp 148ftlbs or so torque and its just not enough to launch them. Even when holding the brake and reving to 2-3k and launching its still not the same as a 5spd launch.

[peanotation]

true. people say autos are better for racing, but this is sometimes true. you can shift a lot faster in an auto than any other human being in an manual, but (with mitsubishi autos) the power transfer on an auto is a lot shittier than on a 5spd.

[ako]

I think I got misunderstood there.. EVERY auto I've ever driven has been a POS compared to the 5sp equivalent in the same car - even the tiptronics which were so vaunted when they came out. (Bearing in mind, the first ones came about in the 1950's :shock: )

I can understand in some drag cars - an auto can be built a LOT tougher than a manual. Dunno why, just the way it works I guess. But still - ESPECIALLY in lower powered cars, an auto trans just saps away far too much power. Plus in an FWD, you're not too worried about mulching a driveline from massive shock you'd recieve from a 6K clutch dump.

Just thought I'd try and see the method behind the madness there - I can see the good side of an auto, my Dads 350ci Holden (Like a 4 door one of those Pontiac GTO's you guys got recently) is one hell relaxed car. Ditto for my mates Legnum VR4 - however its costing him approx a full second on the strip. Horses for courses at the end of the day I guess!

[peanotation]

oh no, you're completely right. there is just a slight advantage to automatics because they shift quicker. but i for one hate them for lower end racing/daily driving. manuals are far superior for many reasons. automatics are used for higher end 9 second car drag racing because they are built to take over a thousand horses and that's their only job, to get the 1/4 mile done in 9 seconds. however, we do not drive 9 second cars, but there are a lot of people on here that love automatics. i have no idea why

[Dark7GHawk]

One example of why an auto can be better.

The MK4 Supra.

The A/T stock is good for about 600 hp/tq, modded, closer to 1000. On average, with a stock tranny and higher stall tq converter, you can launch better than a 6 spd.

Why?

6 Spd - 1st gear is so tall and the power application soooo pure through that Getrag tranny ( good for over 1500 hp stock - Damn Germans... ) that you literally burn tires or brake axles, slipping it is too hard on the car to be any good to most racers.

I have seen some that can launch the Supra 6 spd correctly and go really fast, but its rare and mostly driver skill.


So you either have a drag car (A/T) or a good driver/twisties car (M/T)

[brandon]

#1 reason autos are better than manual:

BEING LAZY.



I'm really leaning toward the Level Ten shiftronic just so I don't have to worry about the stock shift points. That thread on another forum really got me thinking...

[seth98esT]

Dont say autos are for drag cars and 5spds are not. John Sheppard runs a 5spd 1990 Eagle Talon TSi AWD and runs mid 8 second passes in the 1/4. No computer shifting for him, he has pure power. O and its not a shell car either, almost full interior and street legal(minus the slicks) 8)

[Dark7GHawk]

My post was not intended as an end all be all, just an example with the Supra.

[seth98esT]

I know, but everyone thinks that Built auto -> built 5spd on the track. It may be able to shift a tad faster, but that is not our case. We do not make enough power to take advantage of the auto. With a good driver and a 5spd tranny it will take you a long way.

[Dark7GHawk]

I haven't driven an A/T version of the DOHC Galant, but I can imagine the power is better applied through 5 spds like mine.


On the subject of trannies.

1. is there a better manual that I can bolt onto my 7 bolt rather than the F5M31? Would the F5M33 fit, would it be any better.

2. How hard is it to alleviate a bad syncro? Would changing to Syncromesh fluid change it ?

[seth98esT]

Not sure on the tranny codes, F5M31 is 7g correct? I know 2g trannies fit if you use the 2g axles, but I dont know the codes.

And my trannies secnod gear synchros maybe shot but I am going to use BM synchromesh tranny fluid to help them till I get a rebuild. When synchros go out, your tranny will grind at you like you are bad at shifting whenever you put it into gear...

[Dark7GHawk]

I have 2 reasons for thinking the syncro's are going.


1. If I stop at a light, sitting there in gear, clutch in -> Gear to neutral , clutch out. then clutch in, gear into first, when I push into first, it grinds but goes in. Only sometimes does it do this.

2. Sometimes when I shift hard from 1st to 2nd while accelerating hard I get a sound but very little feel and the gear still goes in.

Hmm. A lot of information, but only seth's posts even come close to really answering the question.
Like just about every other "vs." question in automobile modification, auto vs manual comes down to "What's my application?" The reason that the auto seems shittier than the manual to the poster is probably because he has never driven a fast, torquey automatic.
Automatics are all about launching and shifting. They put much more torque to the wheels on launch than a manual, and are easier to launch as well. Nothing can out-shift a well built automatic, either. Think of how much time you spend out of the throttle at the track when shifting, and then drop almost all of it: There's a huge advantage right there. The downside to an auto is a result of the fluid transfer medium. Because of the way the tranny is built, the output shaft of the motor is never spinning at the same speed as the input shaft into the transmission. Energy, and therefore force, is lost when power is transferred through the fluid. This is why autos have a much higher power loss through the tranny. This is why auto models tend to be slower in the quarter than manuals (also can be due in part to some difference in gearing that almost always is the case between autos and manuals).
In autocross racing, manual is no doubt the way to go. Being able to manually select your gears, engine speed, and adjust wheel vs engine speed far easier far outweighs any advantage in shifting time, and obviously launching is not an issue.
Oh, and manuals will always be able to handle higher power numbers to the wheels. Once you're locked in, you're locked in. there's no slipping or anything between the motor and tranny...it's like a solid connection, provided your clutch(es) is/are in good shape. Top Fuel dragsters utilize a clutch. It's very different from a normal transmission, because it is basically a clutched automatic. HP estimates from those are around 8000 at the wheels, btw.

[brandon]

Hmm. A lot of information, but only seth's posts even come close to really answering the question.

You're crazy... being lazy is a perfectly good answer.