Automatic vs. Manual

[MEJ1990TM]

Automatics don't need a massive 1st ratio because torque converters multiply torque, usually around 2:1 while being flashed, and slippage isn't a massive loss. So an automatic with a stall speed at peak torque will need roughly half the overall ratio of a manual and still have more torque on initial launch.

While I can't disagree with what you are saying, I will say that I have seen both automatic ,and stick shift, cars pull down some equally impressive 60 foot times.

 

[McLaren]

On to shifting as fast as an automatic. Have you seen guys that power shift? When you have guys who can hold their foot to the floor and bang gears without hearing any audible increase in RPM you had better believe they are every bit as fast as an automatic. Even with the little bit looser consistency I'd take a four gear over an automatic any day. No fun dropping it in drive, and if you've got a manual valve body it just isn't the same.

So why is that automatics are the preferred choice of drag racing, & not 3 pedals and a stick?

I also don't believe any man can shift a car in .1 of a second because that's how fast the Ferrari SuperFast-II is rated at.

 

[MEJ1990TM]

So why is that automatics are the preferred choice of drag racing, & not 3 pedals and a stick?

How many people do you know that can come through a full blown power shift without either hitting their rev limiter or scattering their bottom end? 💡

I can't do it. The closest I've come is about half throttle. After that I lost my nerve. Even though I am not hearing any increase in RPM when I do it I am not about to go past that point without having a rev limiter of some kind.

 

[Rotary Junkie]

While I can't disagree with what you are saying, I will say that I have seen both automatic ,and stick shift, cars pull down some equally impressive 60 foot times.

True, it's just that automatics are a lot easier on pretty much everything. Also of note that when you "break" an automatic it's usually the clutches that go rather than hard parts. If you start breaking hard parts you've got issues.

So why is that automatics are the preferred choice of drag racing, & not 3 pedals and a stick?

It really is only the preferred choice until you get into the really quick stuff where dog box manuals take back over. Reliability, consistency, and speed right up until the money involved in the car makes it pointless not to go to a Liberty or the like.

 

[niky]

How many people do you know that can come through a full blown power shift without either hitting their rev limiter or scattering their bottom end? 💡

I do it in my truck. Every day.

Helps, of course, that it has about 80 horsepower, revs like a windmill (read: slow), and revs out at around 3800 rpm. I couldn't powershift in my other cars to save my life.

I used to flat-shift when recording times, but after blowing third gear (on my car) doing that, I've stuck to regular shifting when working with test units.

 

[McLaren]

It really is only the preferred choice until you get into the really quick stuff where dog box manuals take back over. Reliability, consistency, and speed right up until the money involved in the car makes it pointless not to go to a Liberty or the like.

What defines the really quick stuff? Because the transmissions in the fastest cars are not true manuals; the gear changes are changed by a simple push or pull of a lever with the clutch hardly involved except to keep the tires from breaking lose. Others are usually 2-speed autos.

 

[Rotary Junkie]

What defines the really quick stuff? Because the transmissions in the fastest cars are not true manuals; the gear changes are changed by a simple push or pull of a lever with the clutch hardly involved except to keep the tires from breaking lose. Others are usually 2-speed autos.

Exactly. But they're still a "manual" gearbox in terms of mechanics.

 

[Kent]

Id say this is fully dependant on car and location. In cities like gulfport a manual stick shift is fine. With something like my honda its easy, with a 12 cylinder lambo it could get to be a pain at times.
In denver, san fran, and newyork I wouldnt think of driving my si, maybe a good dsg but even then it would be used primarily as an auto.

Location and car plus driver knowledge and preference.

 

[Ibonibo]

Prefer Manual (not the guy), for me it's simply more fun to drive,
but the new double clutch automatics are not bad, some beeing even faster than manual, but i like my manual and my clutch.

 

[poolhaas]

Manual for me!

 

[Prince.M5]

Driving a manual car is fun, definitely. Playing around with the clutch, heel-and-toe etc. But for god sake, this is Malaysia. Traffic congestions, looong wait for traffic light with a lot of traffic lights and bla bla bla... I still choose Manual but since we have those kind of situations I'd consider an Automatic as well. In the end I'd rather have a Semi-Auto car...

 

[Kent]

Btw I didnt vote be cause of the situational nature of my preference. As you can see in my sig, I drive manual but in the end I have no problems with a decent auto when the situation dictates auto over manual.

 

[homeforsummer]

CVTs certainly have their place in hybrids and electric cars, where the computer can finely control both the engine/motor and the transmission for the best economy.

EVs don't use CVT Most are either direct drive or use a reduction gear. It's just about the most simple, rudimentary transmission possible.

 

[Keef]

While I can't disagree with what you are saying, I will say that I have seen both automatic ,and stick shift, cars pull down some equally impressive 60 foot times.

While the launch is important, there is more to it than that. You probably won't be shifting out of first gear within 60 feet. Because of the torque converter's action, an automatic can get away with a much longer first speed, so long that many manuals will have shifted twice by then. When your first shift comes soon after 60 feet right in the middle of very rapid acceleration, being able to stand on it for a bit longer saves a lot of time.

 

[Eric.]

EVs don't use CVT Most are either direct drive or use a reduction gear. It's just about the most simple, rudimentary transmission possible.

I was thinking that didn't sound right when I typed it.

 

[MEJ1990TM]

Manual for me!

That is awesome.

 

[MEJ1990TM]

While the launch is important, there is more to it than that. You probably won't be shifting out of first gear within 60 feet. Because of the torque converter's action, an automatic can get away with a much longer first speed, so long that many manuals will have shifted twice by then. When your first shift comes soon after 60 feet right in the middle of very rapid acceleration, being able to stand on it for a bit longer saves a lot of time.

Of course there is more to it then that, but the 60 foot time is critical in getting a good ET. If the traction isn't there the ET is going to suffer in a big way. I will use the '70 as an example. The fastest 60 foot time I got with that the first time out was 2.67. That is about on par with a bone stock LS6 car. Not good at all. Some of that was lack of experience at the track, but the bulk of it was tires. With a small set of slicks I'm sure the car could shave the better part of ,if not a full, second off that 60 foot time. That takes it from a pretty slow ET, to not doing too bad. With a good set of tires I think the car will get into the low 8's in the 1/8.

The other reason the car ran a little slower was the secondary diaphram spring. I should have checked it before we went racing, but I didn't. It had the black spring. According to Holley that prevents it from opening the secondaries completely. The car ran 75 mph in the 1/8 without getting to full throttle and the secondaries very slowly. That is kind of neither here nor there though.

I think the difference in a stick car needing to hit second and third faster is of little consequence. Even on a speed shift there is very little time to where you are stopping the forward acceleration. Then of course the guys who power shift I don't think there is any difference. When all is said and done a hard charging car is a hard charging car. Whether it's got a stick ,or an automatic. I may not like an automatics but I can ,as much as it pains me, recognize the things they do well.

 

[McLaren]

Exactly. But they're still a "manual" gearbox in terms of mechanics.

Mechanics can be described as one wants, the car doesn't change gears with a user-operated clutch like a traditional manual. The fastest drag cars are closer to that of the transmissions used in current supercars than the 6-speed Supra at the track in terms of how they're operated.

Automatic/semi-manuals are the dominant car at the drag strip, and arguably, the road course as well. In a few years, the manuals only saving grace will be the "driver inclusion" with the vehicle, which as some manufacturers have found, isn't a valid sales tactic at the dealership to sale them.

 

[Eric.]

Of course there is more to it then that, but the 60 foot time is critical in getting a good ET. If the traction isn't there the ET is going to suffer in a big way. I will use the '70 as an example. The fastest 60 foot time I got with that the first time out was 2.67. That is about on par with a bone stock LS6 car.

...My Civic gets better 60fts than that.

Automatic/semi-manuals are the dominant car at the drag strip, and arguably, the road course as well. In a few years, the manuals only saving grace will be the "driver inclusion" with the vehicle, which as some manufacturers have found, isn't a valid sales tactic at the dealership to sale them.

I actually have little doubt in my mind that if I had a Gallardo or something that I would go for the paddle shift trans. With cars that fast, its nice to be able to keep both hands on the wheel and never have to concern yourself with rev matching a downshift. Any hooning you might have been able to do if it had a clutch isn't worth having to bring it to the dealer the next week for a $10,000 clutch job.

 

[Rotary Junkie]

...My Civic gets better 60fts than that.

Quite sure my automatic 4cyl family sedan will do better than that...

 

[Keef]

My cousin's stock-tired Cobalt SS ran 2.1 second 60-foot times all day long.

 

[JJ72]

I actually have little doubt in my mind that if I had a Gallardo or something that I would go for the paddle shift trans. With cars that fast, its nice to be able to keep both hands on the wheel and never have to concern yourself with rev matching a downshift. Any hooning you might have been able to do if it had a clutch isn't worth having to bring it to the dealer the next week for a $10,000 clutch job.

If something is wrong with your E-gear in your Lambo you are looking at a $15,000 service just as well. A the clutch only goes wrong when you mishandle it, the E-gear can go wrong even if you didn't use it at all.

What gearbox should a car go with has a lot with its engine characteristic and overall package though, on a car all teched out and is about absolute efficiency a paddle shift will be closer to the theme, but for a muscle car or more old school sports car a manual has that level of intimacy.

Say a sequential Ford GT, or S2000 will just feel wrong. Faster on track certainly, but for its simplicity it better stay with a manual.

 

[MEJ1990TM]

...My Civic gets better 60fts than that.

So it may. What type of mile per hour are you getting out of that Civic? The Chevelle is a torquey big block with six year old 215/65R15's on the back. I was also running with 35 lbs of air. The car was literally run the way it was driven to the track. Those tires were not designed for the shock of launching a 3800 lb stick shift car. In short the car didn't hook up for crap. Even with it's 2.20 1st gear and 3.31's. I will admit that some of it was my being unfamiliar with how to properly launch a car at the track, but a lot of it was the tires.

I guess you guys can make your jokes.

My cousin's stock-tired Cobalt SS ran 2.1 second 60-foot times all day long.

I would also wager it had better tires than what are on the Chevelle. He could also probably lay into it a lot faster than I could. I couldn't punch it off the line like some wheezing six cylinder could, I had to roll into the throttle at a steady rate.

 

[Eric.]

Civic is currently doing a 9.7@78mph with I think about a 2.3 60' on the stock tires (chirps third gear down the strip, too ). I haven't found the sweet spot for launching it, it'll either a) bog, b) spin then bog, or c) spin like hell.

I think the only way I can really do it any better is to do a lot of feathering from higher rpm, and I really don't care enough to give the clutch that much abuse.

Keef, is that a turbo or s/c Cobalt? My friend has a turbo on Nitto 555Rs and a tune that is running 2.0 60's and I think a 9.03 at around 85mph.

 

[MEJ1990TM]

Civic is currently doing a 9.7@78mph with I think about a 2.3 60' on the stock tires (chirps third gear down the strip, too ). I haven't found the sweet spot for launching it, it'll either a) bog, b) spin then bog, or c) spin like hell.

I think the only way I can really do it any better is to do a lot of feathering from higher rpm, and I really don't care enough to give the clutch that much abuse.

Keef, is that a turbo or s/c Cobalt? My friend has a turbo on Nitto 555Rs and a tune that is running 2.0 60's and I think a 9.03 at around 85mph.

Those are the problems I was having. I'd either spin them outright, get wheel hop, or I'd let the clutch out too fast and it would bog. Towards the end of the day I was getting a feel for the proper amount of clutch slippage.

Next time to the track I am going to hopefully have the 255/60R15's mounted on some 15x8 wheels. I'm going to run them at around 20-25 lbs. Also going to unbolt the sway bar up front. Every little bit helps. The car is really begging for a small set of slicks. I'm thinking a 26x8 will be a small enough tire that it won't go starting to break stuff. Realistically looking for a 1.6-1.7 60 time, and a low-mid 8 second ET at somewhere around 82 MPH. It ran 13.20's thirty years ago when my dad was racing it. I know it's making more power now than it did then.

I've spent quite a bit of time getting the vacuum secondary carb more dialed in. I jetted it up a little bit, and added a regular metering block to the rear so I could run any size jet in there. Since jetting it up in the front and rear, and getting the short yellow spring in the diaphram I'm hoping to see a significant increase in MPH. I was going to run 74's in the primaries (72's are the stock jet for a 3310), but all I had was some 76's. I put the 76's in the front and 84's in the rear. I checked the plugs after driving it around some ,including running it out through the gears, and plugs came back clean. Even on the good old butt dyno I could feel a noticeable difference in how hard the car pulled, and how quickly it got to the point of the secondaries opening.

What I really want to run on the car would be a 750 double pumper. An 850 might be a bit too big considering the cam and heads this engine has. Since I am not power shifting it's costing just so much time each shift when the secondaries get dragged shut and have to open again. I'm sure the secondaries are opening fairly quickly once the engine is buzzing up over 4500, but I think the double pumper would help just enough to make the change worth while. If I was power shifting it wouldn't really matter.

I've run the car out too many times to count on open roads, but real drag racing is far more addicting than I thought it would be.

 

[Keef]

Keef, is that a turbo or s/c Cobalt? My friend has a turbo on Nitto 555Rs and a tune that is running 2.0 60's and I think a 9.03 at around 85mph.

G85-package supercharged car. He must have stumbled upon some super secret launch method that really got the LSD cooking, plus the trans would allow the fastest shifts I've ever seen. Only engine mods were an intake and gutted cat, but at launch on stock tires a little power won't help much. He out-launched and beat 3 other local "stage 2" SSs on the regular, just because the other guys couldn't launch worth a crap. I always found that car painfully difficult to drive even on the street, but whatever. He says he's got a 14.1xx time slip, but I've only seen the 14.25 at just under 100. When all the magazines were running 14.6...

 

[Eric.]

Magazine times are reportedly slow in every way for my Civic, too. Somehow Inside Line has the 2012 Si doing a 7s 0-60...

But we're getting offtopic. Back to why clutches are better.

 

[fitftw]

 

[Keef]

But we're getting offtopic. Back to why clutches are better.

The satisfaction one gets from finally perfecting the machine, having practiced endlessly for years to skillfully extract every last drop of speed the car is capable of. Driving a manual is more than just kicks, it is a competition with yourself to perform better today than you did yesterday; the goal is to compete and win, whether it be for yourself, the satisfaction of your passengers, or the guy next to you at the starting line.

 

[wfooshee]

But we're getting offtopic. Back to why clutches are better.

I was just going to ask when this thread became the front-drive drag race thread. . .