: Horsepower and manual transmissions



orconn
06-17-11, 03:59 PM
I am wondering how much the horsepower of the engine the manual transmission and clutch are attached to effect how smoothly and lightly the trans and clutch operate?

From my experience the higher the horsepower the greater the effort involved in operating the clutch and transmission. For instance Miatas are know for the lovely trans operation and their light clutch action. Same goes for many of the small displacement Japanese and European imports. However, my experience with much more powerful engined cars such as Corvette, Jaguar and Lamborghini, Aston, Ferrari and Maserati all of which required considerably more effort to operate. Even a 200 HP Mercedes with a manual transmission required considerable more effort than the smaller displacement Asians or even my 1.5 liter Volkswagen Scirocco, which was so light and nice a child of little experience could drive it.

I would think the extra effort might well make a manual transmission tedious and uncomfartable for a 4000 pound car with 300 horsepower daily driver.

drewsdeville
06-17-11, 04:02 PM
You get used to it after a while. When I first started driving truck full time, my leg actually get a little sore after a day of driving in the city. After a while, it was almost effortless, with no comfort issues. Those tractor clutches are a lot stiffer than some puny sports car.

orconn
06-17-11, 04:06 PM
You get used to it after a while. When I first started driving truck full time, my leg actually get a little sore after a day of driving in the city. After a while, it was almost effortless, with no comfort issues. Those tractor clutches are a lot stiffer than some puny sports car.

So what is your opinion, is heavier effort necessary for the operation of a higher horsepwer car with a manual transmission or not??

Submariner409
06-17-11, 05:56 PM
Ummmmmmmm......................Clutch operation effort depends on the total package: A small car with little opportunity to "overdrive" the attached clutch can use less plate pressure = less foot pedal effort. Any car that is capable of transferring healthy amounts of power to the transmission will, of necessity, need higher plate pressure = higher foot pedal effort...........BUT...........engineers can do magic with mechanical and hydraulic advantage - levers and cylinder diameters. So, clutch pedal pressure depends on a lot of factors, but the inescapable fact is that higher horsepower demands larger clutches with higher plate pressures. Practically, Grannie is not expected to be driving a Ford GT (a real one) or a Ferrari - although there are exceptions.

gdwriter
06-17-11, 06:28 PM
I did a classic car inspection of a 1960 Corvette last week with a dual-quad 283 and a Muncie 4-speed (not numbers matching). The clutch was a little heavy, but not oppressively so, and I adjusted to it easily. Had the same experience last year with a '69 Olds Cutlass W-31, also with a Muncie 4-speed. Last summer, LS1Mike let me drive his Trans Am WS-6 and told me the clutch was heavy, so "don't worry if you stall it out." It was heavy, but I never stalled the only one of Mike's friends to achieve that. Not bad for a lazy automatic driver.

Other than muscle cars, most of my stick shift experience has been with 4-cylinder imports, and the clutch on those cars has always been light and easy. The '74 Celica I drove through high school and college was fun to run through the gears. Light clutch and slick, positive shifting. That's another difference from the muscle cars; those old Muncies tended to be stiff through the gears. Mike's Trans Am was in between, not as slick as the imports or as stiff as the Muncie.

Where a stick gets tedious for me is in heavy traffic with a lot of stop and go driving. Also, an injury to my right shoulder was aggravated by the constant shifting in Phoenix traffic. I'd enjoy having another first-generation Celica or another little sporty car with a stick as a fun weekend car.

Submariner409
06-17-11, 07:19 PM
IIRC, My '65 Chevelle Malibu SS 327/350 Muncie (no power steering, no A/C, no power brakes) was an unholy bitch to drive in downtown Charleston (or Naples, Italy) traffic.

Night Wolf
06-17-11, 07:20 PM
I don't think it is directly related. Atleast I haven't experienced it on my vehicles.

BMW typically has a very heavy clutch pedal, that gets heavier as the clutch wears. Of the manual transmission vehicles I've owned/driven, my 3 BMW's were the heaviest. In comparison, my Jeep has rather light clutch. In heavy traffic does the BMW clutch bother me? No (and I've been in very heavy traffic...) but my leg reminds me it's there (that's not a bad thing). The Jeep however, isn't heavy enough to cause any extra strain on my leg. That engine has more HP and torque than any of the BMW's and it is very light.

As for transmission - all 3 of the Getrag boxes in the BMW's have been flawless, regardless of miles. The weak part is the factory linkage and bushing system. Even when rebuilt it is only "good enough", though there are impressive aftermarket solutions. In the 528e, I installed the Z3 1.9 shifter and upgraded bushings (all bought for the e30 but had anyway). This is a factory short shifter in the car, throws are much shorter (though still not overly short) and as such, shift effort increased, but it gives a nice positive feel going into gear.

The Jeep has a Mercedes transmission that is very easy to shift but doesn't feel that great. It is very picky about how and when it's shifted and overall is rather pathetic that even a brand new (reman) has no comparison to a 25y/o ~300k box with questionable past. In it's defense, it isn't a "car" transmission, but a medium duty truck transmission. Treat it as such and everyone gets along, mostly.

Submariner409
06-17-11, 07:26 PM
:sneaky: Jeeps are just, so,.................[gush, faint, wee-wee] wonderful. I learned to drive on a real post-war Willys Jeep that belonged to Dad..........and he admitted it was the biggest POS he ever bought. It was fun in the winter - towing neighborhood kids around on snowy streets.

Night Wolf
06-17-11, 07:35 PM
:sneaky: Jeeps are just, so,.................[gush, faint, wee-wee] wonderful. I learned to drive on a real post-war Willys Jeep that belonged to Dad..........and he admitted it was the biggest POS he ever bought. It was fun in the winter - towing neighborhood kids around on snowy streets.

As much similarity as there is to a Willys and a TJ -The operating and driving feeling is extremely different.

orconn
06-17-11, 08:36 PM
I n my experience recent Mercedes passenger car manual transmissions are really primitive compared to a Getrag in a BMW. I am told they loosen up as they accumulate some miles, but initially they are not a pleasure to use and I would venture a guess that they would never equal the smoothness and relative precision of the BMW transmissions. My experience with ZF transmissions, both manual and automatic, has always left me impressed with their performance at the higher HP and vehicle weight levels.

For those that want to tolerate a heavy clutch and heavy feeling transmission in their daily driver be my quest. But for slogging through L.A. or D.C. rush hour traffic (which is present for at twelve hours of the day, I'd prefer the convenience of a good automatic trans. For me, with its' smooth operation, relative silence and comfortable seats my 4th generation Seville suits me just fine as a daily driver. And as my only car now it does all the other jobs I require of it. Is it as fun on the twisties as my Old Alfa 164? No it isn't and for certain kinds of driving a BMW 3 series would be more fun, but for my all round needs now I am more that happy with the Seville!

ben.gators
06-17-11, 09:46 PM
Well, I have had very limited experience with manual transmissions. When I was in Europe I drove manual cars couple of times. What I understood are:

1) manual transmission is not as smooth as automatic transmission. The partial reason could be my lack of experience in driving a manual car. However as I was checking the other drivers, it seemed that the transmission was not very smooth even if the driver is very experienced.

2) In manual transmission a driver is almost always busy with changing gears and playing with the clutch, specially in city driving. That is not that much convenient.

3) Clutch was not that much heavy in I-4 cars that I drove.

gdwriter
06-17-11, 10:24 PM
1) manual transmission is not as smooth as automatic transmission. The partial reason could be my lack of experience in driving a manual car. However as I was checking the other drivers, it seemed that the transmission was not very smooth even if the driver is very experienced.It really does depend on the driver. A few years ago, on a visit to Phoenix, I borrowed a friend's '97 Honda Civic 5-speed. Just for fun, I tried making each shift as imperceptible as possible, which a good automatic will do, particularly after the 1-2 shift. Unless I really paid attention to the process, the shifts were never quite as smooth. Not that the car was going all herky jerky, but you definitely feel each shift.

EChas3
06-17-11, 10:27 PM
Show me a smooth driver with a stick and 9 times out of 10 you'll find a car with premature clutch wear. The more time spent near the friction-point, the more wear.

Night Wolf
06-17-11, 11:57 PM
Show me a smooth driver with a stick and 9 times out of 10 you'll find a car with premature clutch wear. The more time spent near the friction-point, the more wear.

You are welcome to ride along in the 528e :cool:

Just let me know before hand you'd like me to drive smooth - and not like I stole it. I can shift that Getrag without any noticeable movement to the car, using (quickly, not overly slipping) the clutch.

What you may "feel" is the acceleration once in gear and throttle is applied again, but even then it is determined by driver input - feel less if not as heavy on the thottle. I'm quite impressed by how well the old tank can do both the smooth luxury car thing and raw sport thing so well, at any given time.

That's another fun thing about the manual transmission - it gives the driver all sorts of things to improve on depending on desired outcome. Rev matching when double clutch down shifting is fun. Also helps get to know your particular vehicle and engine. Of someone would have to actively be trying to learn. Some folks learn the basics of a clutch and stick with it for the rest of their life. I've been in vehicles where the driver feathered the clutch to stay in place when stopped on hills and didn't think anything of it when I asked them why they were doing that. I've also had people ride in my cars (and Jeep) and didn't understand how the shifts could be smooth. Apparently they thought a manual transmission means really rough, jerky shifts that rock the whole car.

As a gearhead, when driving a manual transmission, I enjoy the feeling that the engine is actually connected to something that I have control over, engagement of the clutch as well as shifting the gears. Not just running a hydraulic pump with the only control being "more" or "less".

Jesda
06-18-11, 02:05 AM
The Volvo S60 T5 I owned was a wonderful car, but I let it go because it has a heavy clutch, which I wouldnt have minded if I didnt have to endure stop and go traffic to get to school that semester. And the weight of the clutch pedal wouldn't have bothered me if I didn't have issues with my left knee.

My old BMW 5-series also had a heavy clutch, which made it a bit difficult to use when trying to reverse or do a tight maneuver. I did eventually get used to it.



The Mustang V6 I owned for 6 months was very easy.

Aron9000
06-18-11, 03:07 AM
My old Z28 Camaro with the LS1, t-56 tranny was pretty beast. It had an aftermarket clutch, heavier than stock. It was easy to use though, and I got used to the heavyness after a few days. It also had an aftermarket shifter, which is kind of manditory with those cars because the stock one was very sloppy and vauge. It did require a little bit of muscle and intention to get it into gear. If you didn't give it a firm hand, it would kind of half engage and grind when you let the clutch out. Nothing wrong with the tranny, it just wasn't in gear.

I let my dad borrow that car for a week while I moved and had his 2004 Tacoma. I remember him getting back in his truck and commenting he thought the clutch on it was broken it was so light. I really hated driving that truck because the takeup on the clutch was like a light switch, either on or off. I was always unintentionally spinning the tires on that thing, especially with no weight in the bed.

In contrast my 93 Toyota has a wonderful clutch, easy to use, light, shifts are kind of long but very positive. I could comfortably drive that thing in stop and go traffic all day, something I couldn't say for that Camaro.

C&C
06-18-11, 10:13 AM
With introduction of the hydraulic clutch activation, a lot of force is mitigated, compared to a cable actuated clutch. Even big horsepower engine/clutch combinations can have smooth and relatively light pressure requirements.

Submariner409
06-18-11, 10:33 AM
As a gearhead, when driving a manual transmission, I enjoy the feeling that the engine is actually connected to something that I have control over, engagement of the clutch as well as shifting the gears. Not just running a hydraulic pump with the only control being "more" or "less".

I agree with the manual "feeling of connection" but it's also worthy of note that the 4T80E with TC lockout in my STS (P,R,N,D,3,2,1) can be driven like a clutchless manual all the way to redline in all 4 gears. Far more desirable than a stick which simply says P,R,N,D and L

DouglasJRizzo
06-19-11, 12:35 PM
The Aston V8 Vantage I drove required near herculean efforts for the the clutch and shifter, similar to my old Ford L700 rollback. I think much has to do with clutch size, and the massiveness of everything behind it.

jayoldschool
06-19-11, 05:38 PM
Depending on the year, the Aston Martin uses the T56, same trans used in the Viper, the Corvette, CTS-V, the Camaro, and my Impala SS. I don't find it to be a big effort on the pedal, but it is certainly more than the the average 4 cyl commuter. My wife doesn't like driving it much, though.

DouglasJRizzo
06-26-11, 08:22 AM
It was an 84 V8 Vantage, 5 speed, with engine mods by Nimrod.

jayoldschool
06-26-11, 07:26 PM
Yes, the later ones went to the T56.

brandondeleo
06-27-11, 05:30 AM
I much prefer automatic transmissions, but I am a fan of comfort and luxury, not sportiness. (Hence, I own a DeVille. Haha) I think having an automatic with an auxiliary 'slapstick' like our '06 Charger R/T is nice, because it gives you some semblance of a manual without all of the work. Lol.

Jesda
06-27-11, 11:07 PM
Horses and manual transmissions:

http://www.youtube.com/watch?v=JFjxd67j8jo

Mazda "gets it"

Stingroo
06-27-11, 11:10 PM
I was view number 6666 on that video.

Cursed, yo.

Playdrv4me
06-28-11, 03:34 AM
I agree with the manual "feeling of connection" but it's also worthy of note that the 4T80E with TC lockout in my STS (P,R,N,D,3,2,1) can be driven like a clutchless manual all the way to redline in all 4 gears. Far more desirable than a stick which simply says P,R,N,D and L

I've come to prefer this arrangement even over the so-called "tiptronic/autostick" style trannies in many cars. The Seville seems to respond damn near instantly when I pop that shifter back to the "3" or "2" for instant passing power or whatever other trouble I can find to get into. It also helps that it was an extremely well designed shifter handle and gate "feel". Even though that part is purely aesthetic.

Aron9000
06-28-11, 01:30 PM
^ Yeah the setup in the Seville is actually a take off of an old Mercedes design. Its infinetly better than just having a console shift that just goes straight forward and back, when you have to move it a different direction to select a different gear, its very hard to flub up and accidentally go up or down two gears instead of one.

gdwriter
06-28-11, 05:55 PM
I've come to prefer this arrangement even over the so-called "tiptronic/autostick" style trannies in many cars. The Seville seems to respond damn near instantly when I pop that shifter back to the "3" or "2" for instant passing power or whatever other trouble I can find to get into. It also helps that it was an extremely well designed shifter handle and gate "feel". Even though that part is purely aesthetic.I agree, downshifts are immediate, and I'll sometimes use it to downshift before entering a tight turn so I can accelerate out of it more smoothly because I'm already in the right gear. Manual upshifting is less immediate, both in the Seville and in manumatic cars I've driven. But that's probably because my timing may be off and I'm still accelerating. So I just slide it back up to D and let the TurboHydraMatic do its job, which it does well.

The rental Altima I had recently, even though a CVT, still had a mode for manually "shifting." I found it more of a gimmick than anything else.

Jesda
06-28-11, 06:07 PM
I agree with the comments about 4T80E. Its one of the finest automatics, ever.

Koooop
06-29-11, 12:40 AM
You are welcome to ride along in the 528e :cool:

Just let me know before hand you'd like me to drive smooth - and not like I stole it. I can shift that Getrag without any noticeable movement to the car, using (quickly, not overly slipping) the clutch.

What you may "feel" is the acceleration once in gear and throttle is applied again, but even then it is determined by driver input - feel less if not as heavy on the thottle. I'm quite impressed by how well the old tank can do both the smooth luxury car thing and raw sport thing so well, at any given time.


It's been a long time, but didn't the 528e hit the rev limiter at something like 4,500 RPM? Hardly enough time in the Horsepower curve to really feel the power or the transmission.

cadillac kevin
06-29-11, 12:54 AM
I was always told that you burn up an automatic trans by driving it like a manual (manually shift between 1, 2, D , OD). is that true?

Rodya234
06-29-11, 01:07 AM
I agree with the comments about 4T80E. Its one of the finest automatics, ever.

I'm glad the 4T80e is as good as it is, because the 4T60e was disappointing, especially in a base deVille. Plus after about 120k all 4T60Es automatically poop themselves.

Aron9000
06-29-11, 01:13 AM
I was always told that you burn up an automatic trans by driving it like a manual (manually shift between 1, 2, D , OD). is that true?

I think there might be some truth to that when manually downshifting since it does tend to jerk the car a little if you do it wrong. Upshifting I don't see how it would, cause its always buttery smooth like a normal upshift. I've never felt the need to fool around with that though, all of my automatic cars have been GM. All of them have been great trannies, they know when to downshift, upshift, shift quickly and smoothly.

Stingroo
06-29-11, 01:18 AM
I think my car had a shift kit installed by the previous owner or something. 1-2 and 2-3 are abnormally hard unless you're REALLY on the gas, but the fluid looked great when I drained and refilled it back in December, and there were no flakes in the filter or anything when it was cut open.

Doesn't bother me really. I'm pleased with my 700R4. I don't really know much about transmissions.

I too have also heard that manually shifting an automatic is bad for it. Anyone confirm/deny?

Jesda
06-29-11, 01:20 AM
I'm glad the 4T80e is as good as it is, because the 4T60e was disappointing, especially in a base deVille. Plus after about 120k all 4T60Es automatically poop themselves.

Mine hit 200 and kept on going.

I wasn't gentle with it either, initiating my ownership at 130k.

gdwriter
06-29-11, 01:38 AM
With the 700R4 I put in Betty (out of a '90 Silverado), you can slightly feel the 1-2 shift, but 2-3 and 3-4 are virtually imperceptible. So it doesn't feel much different from the original Powerglide. I like that. And the 1,000 RPM drop at highway speed.

Playdrv4me
06-29-11, 04:33 AM
The 4T60E in the green STS did make a whining noise on the 1-2 shift, but it never got any worse, and the transmission always shifted fine all the way up to near 200k as Jesda mentioned. A *couple* of times toward the end of my ownership with that car, on cold mornings in Washington state, it refused to shift into gear at all. It never did that again after I got it back to the Midwest, and I never figured out what it was. Sold it with 192k and never heard anything from the buyers so I assume it's still trucking along now.

Tell you what though, if ever there were a case study for a car beat to hell and back, that one would be it. Car spent most of its life jumping curbs and running down pedestrians in NY. Trans fluid probably wasn't even touched until 150k when the trans pan gasket finally began to leak and was replaced.

Playdrv4me
06-29-11, 04:40 AM
By the way, the 6L80E in the Escalade is garbage compared to the 4T60 and 80 in the FWD Cads, and the perfectly acceptable 4-whatever in the GMT800 trucks. It's one of the few GM transmissions I've been disappointed with, and there's already a large community of repair support and aftermarket modification for it.

DouglasJRizzo
06-29-11, 06:39 PM
Generally, I prefer automatics myself, and I rarely take either of the hearses through the ranges manually. There are exceptions, and my Ranger was a 5 speed, as was one of my Pontiac T/A's, the Aston, and the Ford L700. I currently have a Ford F350 DRW with a granny gear 4 speed.

Both of the hearses are THM 400 transmissions. About as bullet proof as you could want (as is the C6 in my Thunderbirds) but a dated design.

Koooop
06-29-11, 06:49 PM
I think my car had a shift kit installed by the previous owner or something. 1-2 and 2-3 are abnormally hard unless you're REALLY on the gas, but the fluid looked great when I drained and refilled it back in December, and there were no flakes in the filter or anything when it was cut open.

Doesn't bother me really. I'm pleased with my 700R4. I don't really know much about transmissions.

I too have also heard that manually shifting an automatic is bad for it. Anyone confirm/deny?

I was taught only to downshift an Auto if I was giving it a bit of gas and that you should mostly leave them alone. The OD units you need to shift out of OD if they are shifting to often (up hill) or if you are towing. The only older units I shift manually and don't give a crap what I do are TH400's, those are tough. Many of the new units are smarter and quicker than we are so you can't really improve on some of their shifting by messing with them.