4 Speed Automatic vs 5 or 7 Speed

[Vratenza]

Never hear of people forgoing a 7 speed auto for a 4 speed auto if cost is not an issue....

[ER-3682]

many ppl disappointed with jap car maker is also they still die die wanna use 4 speed. just to save some money from the profit. look at subaru. FI liao still die die 4 speed

Most new Subaru are using CVT,like the XV & 2L Legacy,more powerful version are using 5 speed auto,like the Legacy GT,A-line STI,the lastest sports car BRZ are using 6 speed auto.

Edited April 1, 2012 by ER-3682

[Hondafit2008]

forester? 4 speed. but old model ok. legarcy wagon? 150horse liao still 4 speed. well they can say their gear techo super good ok. tribeca? mo**erf**king 258 horse what they mix with it? 5 speed. BRZ, 6 speed yes and nothing else. just simple six-speed automatic with paddle shifts on the steering wheel. S-tronic, PowerShift, SpeedShift MCT. face it they are and so is the france auto maker

[Expertz]

the problem with 4 speeders is that people with 4 speeders always believe that 4 speeds is more than enough

they've never tried 6 speeders and think that there'll be a huge waste of power while switching gears

 

thats why we still have threads like these

they don't know that gearboxes can now switch gears faster than we can blink

[Hondafit2008]

lol the expertz has sopken haha

[Happily1986]

the problem with 4 speeders is that people with 4 speeders always believe that 4 speeds is more than enough

they've never tried 6 speeders and think that there'll be a huge waste of power while switching gears

 

thats why we still have threads like these

they don't know that gearboxes can now switch gears faster than we can blink

 

everyone here discuss about the technicalities of gearboxes and yet you use the opportunity to shoot the users rather than gearboxes themselves. yet another epic bird talk reply by expertz. expert indeed.

[Bullterrier]

Our group of friends all driving the same make and model of cars used to drive up north quite frequently. Mine is an older model so I had 4 speed gearbox while most of them had 5 speeds.

 

The lowest and higher gear ratios are identical cos we hit the same top end speeds and rpms. We had radios so we were able to counter check these on the move. They had an extra gear somewhere between my third and fourth gears. It meant a smoother gear change for them and also a lower rpm for their engines while they are speeding up to the cruising speeds. Once we both get to the highest gears, our cars behave the same.

 

However whenever I want to do an overtaking, my gearbox is in right gears position and I can move off almost straight away while I have to wait for second or two while theirs drop a gear or two and start moving with power. We are all driving Saabs by the way.

 

So I will say a more speed gearbox will get you better rides and fuel consumption but may not be the optimum for performance especially if the highest and final drive gear ratios are the same as it was in our case. Also a more complicated gearbox is costlier to maintain and heavier. I heard horrid stories of my friends driving 7 DSG boxes which gave way and went in for major repairs at the first 10000km.

 

Hope that clears up some myths.

[Yuan]

Yeah. I like driving CVT. Very smooth drive, drive uphill genting quite a pleasure. I never driven 6 or 7 speed before so I not too sure whether it can beat the smoothness especially when going up and downhill.

 

Having driven a CVT for more than 5 years and now on a 7 speed DSG, there are pros and cons in using different gearboxes for different vehicles in the way we drive.

[Hondafit2008]

So I will say a more speed gearbox will get you better rides and fuel consumption but may not be the optimum for performance especially if the highest and final drive gear ratios are the same as it was in our case. Also a more complicated gearbox is costlier to maintain and heavier. I heard horrid stories of my friends driving 7 DSG boxes which gave way and went in for major repairs at the first 10000km.

 

more speed gearbox will get you better rides and fuel consumption - right

 

but may not be the optimum for performance especially if the highest and final drive gear ratios are the same as it was in our case. - wrong - if this is the case find 1 current performance car with 4 speed (don place subaru in the picture)

 

Also a more complicated gearbox is costlier to maintain and heavier - right (just like a non cam handphone bite the dust you lost the phone list and sms compare to a cam phone you lost extra thing like nude photo. but you already know you are paying more for the phone cos it got a bloddy cam in it)

[Hondafit2008]

However whenever I want to do an overtaking, my gearbox is in right gears position and I can move off almost straight away while I have to wait for second or two while theirs drop a gear or two and start moving with power. We are all driving Saabs by the way.

 

cos with two diff gear setting the overtaking result is diff too. you at 4th gear traveling 120, drop instance 3rd gear higher rpm and drag while your fren at 4th gear going 120 and rmp still lower then your how he drop to 3rd? unless he wan gear box Piang!!

[Hondafit2008]

sorry my english not very if you find hard to understand what i'm saying haha

[Yuan]

Actually, whatever speed a gearbox can be improved with modern technology, I would still prefer and go with a manual transmission anytime.

 

Sturdy, reliable and fun to drive with.

[Kelpie]

forester? 4 speed. but old model ok. legarcy wagon? 150horse liao still 4 speed. well they can say their gear techo super good ok. tribeca? mo**erf**king 258 horse what they mix with it? 5 speed. BRZ, 6 speed yes and nothing else. just simple six-speed automatic with paddle shifts on the steering wheel. S-tronic, PowerShift, SpeedShift MCT. face it they are and so is the france auto maker

 

I doubt Frenchies are using 4AT for their new car models..may be 2007/08 onwards, you don't see them already.

 

Regards,

 

[Ooosh]

Try driving a 4-speed and 6-speed rx8 and you feel the difference in performance

[Kazuo]

Try driving a 4-speed and 6-speed rx8 and you feel the difference in performance

 

Mind enlighting me what's the difference in performance?

 

I assume the rx8 you are talking about have the exact same specs and the only difference is the gearbox.

[Happily1986]

more gears may be good on paper but let us not forget that the primary role of a gearbox involves gear selection. if the gearbox tends to select the wrong gear or does gear hunting alot, a million gear ratios incorporated wouldn't save you or your petrol bill.

[Jchuacl]

The characteristic of the engine would play a more important part in determining the optimal number of gears.

 

You certainly don't want the car to shift gears before hitting the optimal torque. Based on my limited knowledge of continental cars, their peak torque comes in pretty early (<3K) as compared to most Jap cars where the peak torque comes in around 4K +- . And hence, having more gears for continental cars is more suitable as compared with Jap cars.

 

That said, those driving manual gears with high rev or high powered (TC/SC) engines will appreciate the gearbox more so as to get the appropriate power at appropriate times.

 

 

more gears may be good on paper but let us not forget that the primary role of a gearbox involves gear selection. if the gearbox tends to select the wrong gear or does gear hunting alot, a million gear ratios incorporated wouldn't save you or your petrol bill.

 

[Happily1986]

The characteristic of the engine would play a more important part in determining the optimal number of gears.

 

You certainly don't want the car to shift gears before hitting the optimal torque. Based on my limited knowledge of continental cars, their peak torque comes in pretty early (<3K) as compared to most Jap cars where the peak torque comes in around 4K +- . And hence, having more gears for continental cars is more suitable as compared with Jap cars.

 

That said, those driving manual gears with high rev or high powered (TC/SC) engines will appreciate the gearbox more so as to get the appropriate power at appropriate times.

 

I feel that the # of gear is a parameter that is actually controlled by the width of the engine power band to be honest. For e.g. diesel engines have narrow powerbands which forces you to upshift whether you like it or not since the compression ratio is so high. Theoretically, my understanding is that if you are able to artificially reproduce more gear ratios using the interplanetary gears within the gearbox, this will enable the diesel car to attain a higher top speed.

 

I also feel that the parameter that governs whether the gearbox should upshift or not isn't the # of gears or the gear ratio itself. It is actually incorporated by design and controlled by the gearbox modulator valve.

 

I still maintain that engines with early or mid range torque bands benefit from having more gear ratios. Ideally i would prefer 6 gear ratios with G1,G2,G3,G4 to be short and G5 and G6 to be relatively taller with G6 to be taller than G5. G6 is to be used only on cruising to save fuel.

Edited April 1, 2012 by Happily1986