AT in Fast Cars..Is It That Bad..?

[solaris=amazing]

I've never driven a manual transmission in my life, then again i'm only 23 and owned only 3 cars. My next car, will most likely be a 96 Z28, 5.7 of coarse, but i was concerned of one thing-the transmission.

Today, i went to check out this hot red one, it was a beauty-then i saw the auto trans, and i was immediatly discouraged. I'm in no way gonna buy one now-maybe mid 05. At first, i was going to finance either a 05 srt4 or a evo-but i love V8's. Nothing like that raw torque. Will an AT in a camaro slow it up really that much?

I remember 3 months ago, me and a friend went corvette *window* shopping, and we where talking to this really cool sales guy while we where checking a mint 96 grand sport vette-the blue ones, yum. Anyway, he said that the AT's where faster than manuals-something with the way they're calibrated (i think thats the term he said), is that true.. If so, how would a 96 camaro compare in MT vs. AT comparison..?

AT's are so much easier (i would imagine) to drive rather than MT's.

[public]

You can shift manually faster on some cars with a LOT of practice.

Ford and GM have/had a vacuum modulator in the shifting process. This slows them down. You can have a "Shift Kit" installed and it will shift faster than most people can shift a manual.

It must be said that it is a lot easier to do a clutch job than rebuild a auto.

Either way you can have a ton of fun. Good Luck.

[Reed]

well if you want to do any racing besides jsut dragging then you probably want a manual that way you can downshift around corners and such. teh auto tranny has more drivetrain losses mostly in the torque converter but for drag racing they are pretty good cause you can preload the torque converter at the line and then jsut let off the brakes and go.

if you enjoy driving then i think you will love driving the manual. in my opinion it is just so much more fun to drive with the manual, especially with rwd.

sometimes car makers do put a slightly more powerful motor in the manual but thats all tuning and calibration.

[public]

Yeah, that is true. I am older so I was just thinking about drag racing. For a nice mountain side country drive you cannot beat a manual.

[solaris=amazing]

They seem like alot of fun.. I've been in my friends 5.0 foxbody stang last year, and man did your neck snap with the manual. And, believe it or not, i was surprised of the authoritive feel of another friends nissan spec V with the MT. Lol, he burnt up his clutch after one month of financing. I feel myself leaning towards a manual.

[calgary_redneck]

Originally Posted by public

You can shift manually faster on some cars with a LOT of practice.

Ford and GM have/had a vacuum modulator in the shifting process. This slows them down. You can have a "Shift Kit" installed and it will shift faster than most people can shift a manual.

It must be said that it is a lot easier to do a clutch job than rebuild a auto.

Either way you can have a ton of fun. Good Luck.

There is so much misinformation here its hard to know where to start
Electronicly controlled transmissions do not use a vacuum modulator, which accounts for almost every gm transmissions since the early 90's. Even before that there are many gm transmissions that did not use a vacuum modulators such as the 700r4 and 200r4 to name a couple.
-shift kits do not replace vacuum modulators they simply decrease the clutch over lap,main line pressure and apply speed (as well as some shift valve changes).

[public]

Originally Posted by calgary_redneck

There is so much misinformation here its hard to know where to start
Electronicly controlled transmissions do not use a vacuum modulator, which accounts for almost every gm transmissions since the early 90's. Even before that there are many gm transmissions that did not use a vacuum modulators such as the 700r4 and 200r4 to name a couple.
-shift kits do not replace vacuum modulators they simply decrease the clutch over lap,main line pressure and apply speed (as well as some shift valve changes).

1.Many of the new ones do still have modulator. My new Buick Century has one-it went bad $119 at GM for a replacement.

2. The most common RWD tranny for GM is the TH350 with a modulator.

3. I did not say the shift kit replaces the modulator. Sorry I was not clear.

[Zgringo]

I don't know where all this information is coming from but almost all F1 Cart cars as well as Pro drag cars and desert racing use automatics. If I'm not mistaken all the cars in the Pikes Peak hill climb used automatics. Next time there's a cart race on TV watch it and listen to the cars. Their's no driver on earth that can shift as fast as a automatic. With the new trick SAW shifting you just push a button to up or down shift and it all happens within 1/100 of a second.
I have 2 cars, one for racing and the other for street, both have automatics. My street car has the SAW and I can shift to any gear I want manually or switch to the automatic mode. In the manual mode to pass depending on the speed I just punch the button to down shift and pass, or in the mountians do the same, just keep the engine in its power band and haul ass. As for power loss with a automatic that's not true, but with a standard it's there every time you touch the clutch. If you going to do everyday driving then a standard is great, but if you plan on doing any type of racing automatic is the only way to go. Much faster.

[Reed]

there is a big difference between an auto that is in a road car and one in a race car. namely (most) race cars dont have torque converters, which is the major drawback (imo) to an auto. now im not sure about this part but im going to type it anyhow. i was under the imppression that in F1 and cart and world rally and some others that they use sequential manual trannys and in cart they can shift without lifting off the gas or pushing in the clutch they jsut push teh shift lever and the engine cuts ignition for a fraction of a second, i believe it is a computer controlled system that shifts but there is no torque converter. i think it is similar to the system in some of the 2003 and up toyota mr-2 spyders. i cant find a link right now but its a 6 speed with a computer controlled clutch and no torque converter. it will not shift untill you tell it to,it will jsut bounce off the rev limiter.

or i might not know what im talking about at all

[Zgringo]

Originally Posted by Reed

there is a big difference between an auto that is in a road car and one in a race car. namely (most) race cars dont have torque converters, which is the major drawback (imo) to an auto. now im not sure about this part but im going to type it anyhow. i was under the imppression that in F1 and cart and world rally and some others that they use sequential manual trannys and in cart they can shift without lifting off the gas or pushing in the clutch they jsut push teh shift lever and the engine cuts ignition for a fraction of a second, i believe it is a computer controlled system that shifts but there is no torque converter. i think it is similar to the system in some of the 2003 and up toyota mr-2 spyders. i cant find a link right now but its a 6 speed with a computer controlled clutch and no torque converter. it will not shift untill you tell it to,it will jsut bounce off the rev limiter.

or i might not know what im talking about at all

Your kinda right Mr.Reed, It's a electric torque convertor rather than a hydralic one used in the more common types. Both my cars have it and it is a real automatic transmission. The electric torque convertor has unlimited stages of lockup, from 0 to totally locked.
I think it could be best described as a multidisk setup similar to that used in AA/Fuel and funny's but electrical controled. The ones I have can be controled by the computer to lock up anytime I want, kinda like what ever stall I so desire. For normal driving my street car I set it for total lockup at 1,500RPM but for draging set at 5,500. They don't call it a clutch, but a varible speed torque convertor. Both cars use buttons to shift (SAW) Shift At Will. I have a switch in both cars that switches between automatic or manuel. In automatic mode shift points can be setup by computer, in manuel it well stay in that gear till I hit the up or down shift button. If I was to place a name on it I'd call it a electric clutch, but the problem is it drives the front pump for the transmission which is a automatic.

[curtis73]

I think its just preference. Certain types lend themselves to better performance in certain situations. I have a BMW E30 that I would probably set fire to if it had an automatic. For me, there is no such thing as an automatic 325i. Blasphemy

I have two classics; a 66 Pontiac Bonneville and a 73 Impala Wagon, and they will both retain their automatics. They are luxo road cruisers. They each have 500 hp, but they're cruisers

I have a 96 Impala SS that is soon to get a T56 manual conversion.

If you're going to drag race with a lightly modified car, its pretty effective to use an auto tranny. They hold torque better and offer more consistent performance. If you're going to autocross, its more typical to see manuals. They hold a certain RPM and the clutch applies 1:1 torque to the tranny. If you had an automatic it might start shifting on its own at the wrong times and just otherwise cause headaches.

So, for the street, its purely preference... vacuum modulator or not. I almost always prefer a manual in most applications. The only time I don't is with luxo cruisers.

Solaris, In your situation (having owned a few RWD auto tranny GMs from that era) what I recommend is to steer clear of that automatic. They aren't terrible... well, yes they are in fact terrible. The 4L60E is not a long-lifer. Mine in the 96 SS lasted about 46,000 miles. Some have reported as few as 30,000 miles before death and some have had no problems for 100k or more. If that Camaro was driven like Grandma's Lincoln, I'm sure its fine, but I doubt any camaro is driven that way. They have problems with heat which cooks the already poor clutches. The valves and solenoids get sticky and cause 1-2 shift flares and sometimes 2-3 shift flares. Overall its a good design that was just very poorly engineered and tuned. Its all fixable with aftermarket parts, but unless you get in there and change those valves, solenoids, clutches, and other parts, its never going to be a good performance tranny.

The other issue you might find is that the computer controlled 4L60E has the oddest shift patterns. It takes monumental right foot input to get it to shift down, and even after you floor it, it takes way too long to down shift. Often times you'll notice that if you're accelerating moderately, then stab the throttle at about 25, it UPshifts to third. Lord knows why, but for an enthusiast like myself, its frustrating. You can reprogram the computer to change shift points and shift firmness, but that just moves the problems to another RPM.

[sunfire_starter]

Originally Posted by curtis73

Often times you'll notice that if you're accelerating moderately, then stab the throttle at about 25, it UPshifts to third. Lord knows why, but for an enthusiast like myself, its frustrating. You can reprogram the computer to change shift points and shift firmness, but that just moves the problems to another RPM.

this is just a shot in the dark because of little I know about cars but if you moved the shift point likle right before redline wouldn't it cause less of a chance to have it shift into third?

[curtis73]

Originally Posted by sunfire_starter

this is just a shot in the dark because of little I know about cars but if you moved the shift point likle right before redline wouldn't it cause less of a chance to have it shift into third?

In theory yes, but in practice no. In my post I mentioned that if you stab the throttle at 25 it sometimes upshifts. Moving the shift points up would make it do the same thing, but at 30 mph instead.

Chaning the shift points on the computer doesn't do much for daily driving. Its at wide open throttle that those points really take effect, so at part throttle you won't be able to change much about the tranny. On my 96 SS I have it set to fully firm shifts and raised the shift points about 300 rpms. If I weren't the principle driver of the car I would probably not be able to tell much difference.

[ales]

Just to clarify, F1 cars use semiautomatic sequential gearboxes that have little to do with the automatic gearboxes that you can operate manually, it's a very different animal.

[RandomTask]

Originally Posted by public

1.Many of the new ones do still have modulator. My new Buick Century has one-it went bad $119 at GM for a replacement.

2. The most common RWD tranny for GM is the TH350 with a modulator.

3. I did not say the shift kit replaces the modulator. Sorry I was not clear.

1. I'm guessing (sorry I'm on reply page and didn't check if its listed in your sig) that for your buick to be RWD its a MID 70's. (I believe 80's/90's Century's to be FWD)

2. The TH350 is not the most common auto tranny for GM. The TH350 came in a lot of the older (69-early 80's) full size cars such as Caprices and Monte Carlo's. The TH-350 was a 3 speed which made it ideal for drag racing. The TH-350 was phased out for the 700-R. (Pre '87 700R's are reputably weaker than TH-350s. It wasn't until '87 did they fix all of its problems). The 700R4 was eventually changed into the 4L60. Eventually they made an electronically controlled unit, the 4L60-E. This has now evolved into a more stronger 4L65-E which is used on Z06's and newer auto vettes. 1990's LT1/LT4/LS1(V-8's) Camaros, Corvettes, and Firebirds used either the 4L60/4L60-E for auto's. For the manual versions they used the Tremec T-56 6 speed transmission. They only current RWD vehicles GM produces now are the GTO and the Vette, both using the same driveline of the 4L65-E or the T-56. There are plenty of other trannys made by GM (including the powerglide, the TH-250, 4L80-E, etc, etc...) I believe the actual most produced GM auto tranny was the 700-R.

3. I wish I could tell you exactly what the shift kit replaces. I installed a shift kit into my TH-350 when I did an engine swap on my '81 Monte Carlo (which originally came with a TH-250). Other than that, Cookies everyone.

In regards to the question. I've cooked several auto tranny's in my day. Auto trannies HATE heat. They will cook themselves to death if you let them. (RIP my old TH-350) if you're gonna go hard on them, make sure you have a transmission fluid cooling radiator, if not, buy one and install it. Generally manuals will either burn the clutch or launch a planitary gear on the input shaft when you abuse them. Don't be scared about the auto though. With a well trained driver on the new vettes, the best they could squeeze out on the 1/4 was 1 or 2 tenths by choosing the manual over the auto. Just remember, if this car is going to be used for daily driving, I personally would choose the auto. (trust me, being stuck in traffic with a manual SUCKS) Also, cars with auto trannies generally have a higher sale and resale value than the exact car with a manaul. A auto-matic WS6 Firebird or LT1 Camaro would still be a LOT of fun! Best of luck, let us know what you get!