I appreciate the TCC locking often as well. And my car's AT shifter has a "sequential" shift mode on the left, so it's easy to tap up and down through the gears if I prefer, of if I'm driving in transient conditions where I don't want a lot of shifting. All AT shifters should be so accomodating, in my opinion.
Driveability Issues with Advanced Powertrains
- Thread starter The Critic
- Start date
- Status
Honestly, I don't feel a need for variable lockup in most trannies. I like a nice, tight torque converter and a solid lockup clutch. My Jeep has a very noticeable lockup compared to others like it (not 5.9s), as its stock converter is a 2300 rpm stall, rather than the 1800 rpm stall most have (which I prefer), and feels much slushier.
Last edited:
Originally Posted By: GMBoy
This is a direct result of CAFE and other regulations. GM will probably offer re-flash if enough people find it annoying. I am also sure the aftermarket will offer power tunes, too.
I wish they would offer an AWD version of the manual Cobalt SS's power/drivetrain for this platform! (Even though I know that's NOT this car's "purpose").
This is a direct result of CAFE and other regulations. GM will probably offer re-flash if enough people find it annoying. I am also sure the aftermarket will offer power tunes, too.
I wish they would offer an AWD version of the manual Cobalt SS's power/drivetrain for this platform! (Even though I know that's NOT this car's "purpose").
Drive by wire is the other culprit. To date the only DBW car I thought felt good was my mom's 2011 Infiniti EX35. Every other DBW car I've experienced just felt disconnected and numb.
Originally Posted By: dparm
Drive by wire is the other culprit. To date the only DBW car I thought felt good was my mom's 2011 Infiniti EX35. Every other DBW car I've experienced just felt disconnected and numb.
Nissan does seem to do its DBW systems very well. Our V6 Altima does not exhibit any of the lag that is typical of DBW systems.
Drive by wire is the other culprit. To date the only DBW car I thought felt good was my mom's 2011 Infiniti EX35. Every other DBW car I've experienced just felt disconnected and numb.
Nissan does seem to do its DBW systems very well. Our V6 Altima does not exhibit any of the lag that is typical of DBW systems.
Is it the "advanced powertrain" or a case of an underpowered car with a peaky engine? My experience has been that they are constantly shifting up and down because they lack any torque at lower RPM's in spite of VVT. A CVT would make sense in these apps. I had an 08 Astra with the 138 HP engine and a 5 speed manual. I required constant rowing of the gearbox because it had absolutely no power below 3000 RPM, and it had VVT. If it would have been an automatic, it would have been shifting constantly in urban environments.
Automatics are NOT as efficient as manuals today. That is a myth. they use lazier gear ratios to get improve mileage.
Well, drive a manual with 2 less 0-60 seconds or less acceleration and there is your 8% gap again. Physics folks.
A torque converter or a CVT is not direct drive, unless locked up.
The underlying message in this thread is driving with momentum and anticipation results in much better mileage with any drive train.
both Cruzes at the Rochester, NY auto show last weekend were manuals! I was surprised.
Well, drive a manual with 2 less 0-60 seconds or less acceleration and there is your 8% gap again. Physics folks.
A torque converter or a CVT is not direct drive, unless locked up.
The underlying message in this thread is driving with momentum and anticipation results in much better mileage with any drive train.
both Cruzes at the Rochester, NY auto show last weekend were manuals! I was surprised.
I love to read all the praises that automatic transmissions get.
You always read how the "modern" automatics are so advanced, high tech and so on. Well, that's great, but why did it take over half a century to match the fuel economy of a low tech, crude manual?
And then you have the really ironic part, most of automatics have a manual mode
You always read how the "modern" automatics are so advanced, high tech and so on. Well, that's great, but why did it take over half a century to match the fuel economy of a low tech, crude manual?
And then you have the really ironic part, most of automatics have a manual mode
Originally Posted By: KrisZ
You always read how the "modern" automatics are so advanced, high tech and so on. Well, that's great, but why did it take over half a century to match the fuel economy of a low tech, crude manual?
I think there are two answers for this. First, and for the most part, few cared about the economy of automatic transmissions until relatively recently. Automatics were all about smoothness and ease of use. If you wanted to be frugal, you bought a manual. Now that fuel is getting tighter again in the last decade or so, and now that a vast majority of the driving public prefers automatics, more attention is being given to fuel efficiency and the automatic transmission. During the 1970s, we didn't have the fluids and materials we have today, so much of the gains we see today were not possible.
And this is the second answer. What we see today is possible through the use of more advance materials, more advanced fluids, and probably most importantly, tight computer control. The control modules of the earliest ECMs back in the late '70s and early '80s don't hold a candle to the processing power built into modern vehicles, so the tight electronic control just wasn't possible.
You always read how the "modern" automatics are so advanced, high tech and so on. Well, that's great, but why did it take over half a century to match the fuel economy of a low tech, crude manual?
I think there are two answers for this. First, and for the most part, few cared about the economy of automatic transmissions until relatively recently. Automatics were all about smoothness and ease of use. If you wanted to be frugal, you bought a manual. Now that fuel is getting tighter again in the last decade or so, and now that a vast majority of the driving public prefers automatics, more attention is being given to fuel efficiency and the automatic transmission. During the 1970s, we didn't have the fluids and materials we have today, so much of the gains we see today were not possible.
And this is the second answer. What we see today is possible through the use of more advance materials, more advanced fluids, and probably most importantly, tight computer control. The control modules of the earliest ECMs back in the late '70s and early '80s don't hold a candle to the processing power built into modern vehicles, so the tight electronic control just wasn't possible.
^ I'm going to have to respectfully disagree. The 1983 chevy cavalier had feedback fuel control throttle body injection. You could pull codes with a paper clip. The 3 speed auto with lockup was mediocre, but the carefully selected final drive had it performing okay on the highway. Ford had the 4 speed overdrive AOD tranny in 1980 and GM had a FWD and RWD 4 speed OD tranny with lockup in their midsize cars in the early 80s as well.
Yes it's been a marketing failure keeping 3 speed autos around the longest on junky small cars like the neon expresso and base corolla. Guess the 4 speeds were too expensive to justify even with CAFE. Or their biggest benefit is closer spaced gears for better acelleration.
The best gains since then have been in knock sensors and VVT and, when they work the bugs out, DI. The curmudgeon in me says we don't need more than 4 forward speeds plus lockup, even with a somewhat lousy torque curve.
Yes it's been a marketing failure keeping 3 speed autos around the longest on junky small cars like the neon expresso and base corolla. Guess the 4 speeds were too expensive to justify even with CAFE. Or their biggest benefit is closer spaced gears for better acelleration.
The best gains since then have been in knock sensors and VVT and, when they work the bugs out, DI. The curmudgeon in me says we don't need more than 4 forward speeds plus lockup, even with a somewhat lousy torque curve.
Yeah, they did okay. I had an '84 Cutlass with a computerized Q-jet carb, with the TH-200-C 3-speed with lockup. The axle ratio? 2.14:1. Performance was rather poor, even with the torque of the V-8. I also owned the 4-speed version (an '87 Regal with the TH-200-4R with 3.08:1 axle), and it was better, but not by a wide margin. I'll bet my cell phone has more computing power than those G-bodies had!
3 or 4 speeds might be fine for the highway, as long as the ratio is set up right.
But 5 or 6 is better for city driving, since there's a better chance that there will be a gear that's exactly right for the speed. There's more to it than the engine's powerband, there's also the "efficiency band".
I won't comment on 7, 8, and 9 speed transmissions.
But 5 or 6 is better for city driving, since there's a better chance that there will be a gear that's exactly right for the speed. There's more to it than the engine's powerband, there's also the "efficiency band".
I won't comment on 7, 8, and 9 speed transmissions.
It really has a lot to do with narrow power bands and engines tuned for emissions that tend to surge at steady throttle. Add drive by wire and 20 speed transmissions ...
I had a '97 Maxima SE 5 speed that you could not go 45 in 5th. It was physically not possible. If you cracked the throttle it would accelerate, let off just a hair and it would slow down. These problems are not new, just worse now.
I had a '97 Maxima SE 5 speed that you could not go 45 in 5th. It was physically not possible. If you cracked the throttle it would accelerate, let off just a hair and it would slow down. These problems are not new, just worse now.
Originally Posted By: CBR.worm
It really has a lot to do with narrow power bands and engines tuned for emissions that tend to surge at steady throttle. Add drive by wire and 20 speed transmissions ...
A lot of these engines don't have narrow power bands at all. Their "max efficiency" bands may be narrow, though. In general I've found that any well engineered forced induction engine can have a very flat, very wide torque curve. Again, I reference design. Test drives of a WRX compared to, say, an Audi 2.7T show completely different levels of "flexibility" and "driveability". The Cruze's 1.4FSI should have good torque for its displacement at a wide range of speeds.
As someone else has already said, a higher number of well-spaced gears increases the chance that you've always got the "right gear" handy for good acceleration out of a turn etc... I know that newer city buses with close-ratio 6 and 7 speed automatics are much better performers and always have the right gear compared to older 3 speed clunkers. Big diesels have even more restrictive "power curves".
It really has a lot to do with narrow power bands and engines tuned for emissions that tend to surge at steady throttle. Add drive by wire and 20 speed transmissions ...
A lot of these engines don't have narrow power bands at all. Their "max efficiency" bands may be narrow, though. In general I've found that any well engineered forced induction engine can have a very flat, very wide torque curve. Again, I reference design. Test drives of a WRX compared to, say, an Audi 2.7T show completely different levels of "flexibility" and "driveability". The Cruze's 1.4FSI should have good torque for its displacement at a wide range of speeds.
As someone else has already said, a higher number of well-spaced gears increases the chance that you've always got the "right gear" handy for good acceleration out of a turn etc... I know that newer city buses with close-ratio 6 and 7 speed automatics are much better performers and always have the right gear compared to older 3 speed clunkers. Big diesels have even more restrictive "power curves".
Last edited:
I don't think the power bands are narrow in today’s engines, quite the opposite is true. With VVT's and variable intake lengths the engines are quite flexible even without forced induction.
However, the power band did move up in the RPM range, and you have to rev the engines much higher then before to get good acceleration. It is not uncommon today even in V6 engines to have peak torque at 4-4.5k RPM range and some Honda 4 cylinder engines are into 5k. Combine this with automatic transmissions programmed to stay in the low RPM range and engines feel like they are out of steam.
Also, I think that a lot of Americans are still used to the old V8 engines that had plenty of low end torque but run out of steam at 5k RPM, people here are just not used to revving their engine. You hear plenty of times people being afraid that their engine will not last long because it revs at 3k RPM at highway speeds, ask any European or Japanese driver, for them 3k is nothing, they are not afraid to wind up the engine to the red line if they want to accelerate, plus they mostly drive manuals.
However, the power band did move up in the RPM range, and you have to rev the engines much higher then before to get good acceleration. It is not uncommon today even in V6 engines to have peak torque at 4-4.5k RPM range and some Honda 4 cylinder engines are into 5k. Combine this with automatic transmissions programmed to stay in the low RPM range and engines feel like they are out of steam.
Also, I think that a lot of Americans are still used to the old V8 engines that had plenty of low end torque but run out of steam at 5k RPM, people here are just not used to revving their engine. You hear plenty of times people being afraid that their engine will not last long because it revs at 3k RPM at highway speeds, ask any European or Japanese driver, for them 3k is nothing, they are not afraid to wind up the engine to the red line if they want to accelerate, plus they mostly drive manuals.
Originally Posted By: KrisZ
Also, I think that a lot of Americans are still used to the old V8 engines that had plenty of low end torque but run out of steam at 5k RPM, people here are just not used to revving their engine.
v8's fell off the map as a popular engine back in the 1980's. That is nearly 25-30 years ago.
Also, I think that a lot of Americans are still used to the old V8 engines that had plenty of low end torque but run out of steam at 5k RPM, people here are just not used to revving their engine.
v8's fell off the map as a popular engine back in the 1980's. That is nearly 25-30 years ago.
So all these big SUV's and trucks of late 90's and early 2000 that were the rage, were powered by V6's or 4 bangers??? I don't think so.
The 5-speed auto in our Fit likes to downshift quickly at any application of the throttle, and get 20 mpg according to the instant FE display on the dash. Back off of the DBW throttle and it'll get significantly better fuel economy. The TCC likes to lock up fast, and is far more load-dependent than speed-dependent. It'll happily cruise at 1100 RPM in 5th gear with the TCC locked up when there's little load on the engine. Then it unlocks the TCC at the drop of a pin, and then shifts when the load is too high for the present gear.
My Buick's old-school "3-speed with overdrive" locks the TCC based on speed, and is very aggressive at keeping it locked. The TCC locks at 30 mph in 3rd, and at 48 mph in 4th. A bit of throttle input doesn't faze it. It just grumbles and pulls.
That's also comparing a 3.8 liter, 12 valve, torque monster pushrod V6 with no VVT to a 1.5 liter SOHC 16 valve cam-phasing engine that has less than half the HP and torque in cars that are 900 lbs different in weight.
My Buick's old-school "3-speed with overdrive" locks the TCC based on speed, and is very aggressive at keeping it locked. The TCC locks at 30 mph in 3rd, and at 48 mph in 4th. A bit of throttle input doesn't faze it. It just grumbles and pulls.
That's also comparing a 3.8 liter, 12 valve, torque monster pushrod V6 with no VVT to a 1.5 liter SOHC 16 valve cam-phasing engine that has less than half the HP and torque in cars that are 900 lbs different in weight.
^ My Jeep is pretty much as you describe your Buick as far as the way the tranny handles, and the pull you get. The larger, old-school pushrod engines love to lug, and have plenty of low end torque.
I agree with Kris as to the V8 vs high revving I4 thing. My Jeep falls flat on its face above 4500 rpm, so it's not a high revver. In daily driving, it rarely sees more than 2500, except for highway merging. It's a much nicer feel than an I4 screaming 6000 to get moving. Plus, I find vehicles that are spinning 3k rpm on the highway tiring to drive, as it's often noisy. OTOH, the Jeep is well under 2k rpm at 60mph, so it's a nice, smooth, quiet cruise.
I agree with Kris as to the V8 vs high revving I4 thing. My Jeep falls flat on its face above 4500 rpm, so it's not a high revver. In daily driving, it rarely sees more than 2500, except for highway merging. It's a much nicer feel than an I4 screaming 6000 to get moving. Plus, I find vehicles that are spinning 3k rpm on the highway tiring to drive, as it's often noisy. OTOH, the Jeep is well under 2k rpm at 60mph, so it's a nice, smooth, quiet cruise.
Originally Posted By: rslifkin
I agree with Kris as to the V8 vs high revving I4 thing. My Jeep falls flat on its face above 4500 rpm, so it's not a high revver. In daily driving, it rarely sees more than 2500, except for highway merging. It's a much nicer feel than an I4 screaming 6000 to get moving. Plus, I find vehicles that are spinning 3k rpm on the highway tiring to drive, as it's often noisy. OTOH, the Jeep is well under 2k rpm at 60mph, so it's a nice, smooth, quiet cruise.
Modern 4-cylinders act like V-8 engines more than they used to. I can drive my 4-cylinder Camry around all day and not see the north side of 2,000rpm if I don't want to (and still keep up with traffic). And at over 80mph, it's spinning at less than 2,500rpm. Yeah, I like the 6-speed auto.
I agree with Kris as to the V8 vs high revving I4 thing. My Jeep falls flat on its face above 4500 rpm, so it's not a high revver. In daily driving, it rarely sees more than 2500, except for highway merging. It's a much nicer feel than an I4 screaming 6000 to get moving. Plus, I find vehicles that are spinning 3k rpm on the highway tiring to drive, as it's often noisy. OTOH, the Jeep is well under 2k rpm at 60mph, so it's a nice, smooth, quiet cruise.
Modern 4-cylinders act like V-8 engines more than they used to. I can drive my 4-cylinder Camry around all day and not see the north side of 2,000rpm if I don't want to (and still keep up with traffic). And at over 80mph, it's spinning at less than 2,500rpm. Yeah, I like the 6-speed auto.
- Status
Similar threads
- Sticky
