6 sp in a 89 SE?
07-26-2003, 11:33 AM
#1
6 sp in a 89 SE?
Hey all,
I would really like a 6 speed due to the fact that at "normal" highway speeds (ok, 70-80 MPH) my engine is revving at 3k RPM. I don't like that and niether does my wallet. If you can't find a 6 speed, is it possible to either swap in a more fuel efficient 5th gear or make a more efficient final drive ratio?
I don't see making a taller 5th gear as a problem due to the fact that 4th hits the speed limiter. Plus, it seems like it's needed anyways.... a 400-500 RPM drop from 4th to 5th doesn't seem to be all that efficient.
Thought? Suggestions?
I would really like a 6 speed due to the fact that at "normal" highway speeds (ok, 70-80 MPH) my engine is revving at 3k RPM. I don't like that and niether does my wallet. If you can't find a 6 speed, is it possible to either swap in a more fuel efficient 5th gear or make a more efficient final drive ratio?
I don't see making a taller 5th gear as a problem due to the fact that 4th hits the speed limiter. Plus, it seems like it's needed anyways.... a 400-500 RPM drop from 4th to 5th doesn't seem to be all that efficient.
Thought? Suggestions?
07-26-2003, 03:05 PM
#3
if my half-as@#$ theory is correct, the existing VG or VE engine and it's resident con rod/piston/crank shaft relationship will not benefit from 6 speeds. the powerband will be same but simply spliced up in 6, closer, places, rather than the stock 5.
more guessing on my part, but i would think that if you are ultimately wanting lower revs with more power, and/or efficiency, you could achieve that with a larger bore. but, then again, you use more fuel ultimately.
a shorter stroke will enable you to rev much higher per gear, topping out the powerband more gradually and then perhaps necessitating 6 gears -like in the later model maximas. notice on the 2k2 max, for example, the tacho redlines farther than on the 3rd gen. but this is a result of the engine's geometry FIRST. not the tranny's.
swap the VQ into the 3rd gen, then, along with the 6-spd gearbox. that would make more sense. in theory.
this all sounds good, but is speculative. anyone have any thoughts on this?
(hint: better engine efficiency can be attained by lightening up the weight of the engine's moving parts and the unsprung weight in general)
more guessing on my part, but i would think that if you are ultimately wanting lower revs with more power, and/or efficiency, you could achieve that with a larger bore. but, then again, you use more fuel ultimately.
a shorter stroke will enable you to rev much higher per gear, topping out the powerband more gradually and then perhaps necessitating 6 gears -like in the later model maximas. notice on the 2k2 max, for example, the tacho redlines farther than on the 3rd gen. but this is a result of the engine's geometry FIRST. not the tranny's.
swap the VQ into the 3rd gen, then, along with the 6-spd gearbox. that would make more sense. in theory.
this all sounds good, but is speculative. anyone have any thoughts on this?
(hint: better engine efficiency can be attained by lightening up the weight of the engine's moving parts and the unsprung weight in general)
07-26-2003, 06:10 PM
#6
they make 6 gear-boxes because the engines they are designing today have a broader powerband. the 6-gears are there to exploit that. and because they are making engines, generally, higher revving, the driver can "top out" the gears farther into them, giving the crank ever more angular momentum. via this concept, you can redline each gear, and, by the time you reach 6th, you are going over 140mph. i imagine with the 280hp G35 coupe, you could probably get up to 150+.
for example, the powerband of a diesel engine in a big rig, tractor-trailer, is so vast that those trannys often have 8, 9, 10 gears --it takes so many "tiers" to get to the super-pulling zone at highway speeds for those vehicles that the driver must climb up more "rungs of the ladder" to get to the sweet spot.
for cars, "normal driving" is not the scope of the 6 gear-box, as most daily drivers will never fully realize the potential of them. they are mostly a "benchmark" for the sales staff to "upsell." and it is macho.
for example, the powerband of a diesel engine in a big rig, tractor-trailer, is so vast that those trannys often have 8, 9, 10 gears --it takes so many "tiers" to get to the super-pulling zone at highway speeds for those vehicles that the driver must climb up more "rungs of the ladder" to get to the sweet spot.
for cars, "normal driving" is not the scope of the 6 gear-box, as most daily drivers will never fully realize the potential of them. they are mostly a "benchmark" for the sales staff to "upsell." and it is macho.
07-26-2003, 07:47 PM
#7
not for nothing, i love my car to death,, but we are talking about a 3rd gen maxima worth 2-4000. sell it and buy something with 6 speeds if it makes you that happy. the engineering involved to make that happen isnt worth the time and money involved
07-26-2003, 08:28 PM
#8
it is not for nothing, i agree, for the enthusiast. for many people, the potential of the 6spd will not be realized, as they are too afraid of it. i drove a 2k2 maxima with 6spd gearbox, and i only could get it to 4th on the test drive. 3rd gear pulled so hard that i was in shock. i believe, too, that it was "only" the 265hp version of the VQ.
07-26-2003, 08:39 PM
#9
yes, it is not for nothing, i agree, for the enthusiast. for many people, the potential of the 6spd will not be realized, as they are too afraid of it. i drove a 2k2 maxima with 6spd gearbox, and i only could get it to 4th on the test drive. 3rd gear pulled so hard that i was in shock --delightfully so, mind you, but a soccer mom would probably not have taken the car to redline. i believe, too, that it was "only" the 265hp version of the VQ. very nice, btw. 5th gens are awesome.
it is like the SUV that is never going to see offroad miles in it's lifetime. it can go offroad, certainly, but most of them never will. it is all image and power and vanity.
it is like the SUV that is never going to see offroad miles in it's lifetime. it can go offroad, certainly, but most of them never will. it is all image and power and vanity.
07-26-2003, 11:30 PM
#10
Senior Member
Join Date: Jan 2003
Posts: 554
Originally posted by bonzelite
yes, it is not for nothing, i agree, for the enthusiast. for many people, the potential of the 6spd will not be realized, as they are too afraid of it. i drove a 2k2 maxima with 6spd gearbox, and i only could get it to 4th on the test drive. 3rd gear pulled so hard that i was in shock --delightfully so, mind you, but a soccer mom would probably not have taken the car to redline. i believe, too, that it was "only" the 265hp version of the VQ. very nice, btw. 5th gens are awesome.
it is like the SUV that is never going to see offroad miles in it's lifetime. it can go offroad, certainly, but most of them never will. it is all image and power and vanity.
yes, it is not for nothing, i agree, for the enthusiast. for many people, the potential of the 6spd will not be realized, as they are too afraid of it. i drove a 2k2 maxima with 6spd gearbox, and i only could get it to 4th on the test drive. 3rd gear pulled so hard that i was in shock --delightfully so, mind you, but a soccer mom would probably not have taken the car to redline. i believe, too, that it was "only" the 265hp version of the VQ. very nice, btw. 5th gens are awesome.
it is like the SUV that is never going to see offroad miles in it's lifetime. it can go offroad, certainly, but most of them never will. it is all image and power and vanity.
For everyday driving, it seems to be more for marketing than anything else. Knowing how the American, consumer mind works, numbers are everything--even though those numbers really mean nothing in normal, everday use. "6? Wow, 6 must be better than 5; therefore, I will take it!" It will be just a matter of time before we see 7 and 8 spd gearboxes. Again, to intice the consumer that this is somehow better for them when they are carring groceries from Food Lion.
It is like the big, diesel pickup truck that will never carry anything more than rain droplets in the scratch-resistant bed. It can carry a house, but most never will.
But hey, who am I? I would like to have a 6spd also so that I can floss when I drive about 10MPH through the parking lot.
07-27-2003, 12:50 AM
#11
bonzelite, you are absolutely correct about the 6 gears being shorter than 5 gears. however the VQ35 6spd is more of a cruiser in 6th.
I believe the VE and VG trannys are different, gear ratio wise as the redlines and powerbands are different. I also recall some info about altima or sentra gears working in our trannys (VQ atleast).
Best highway cruiser is an Auto, simple as that, but things could be worse, could have extra cylinders with a less efficient engine.
best bet, buy a lightened flywheel for better economy and more fun. Granted you cant justify spending $350 to get better mileage, but you also have to determine how much fun you want to have with the car.
Underdrive pulleys help out too!
I believe the VE and VG trannys are different, gear ratio wise as the redlines and powerbands are different. I also recall some info about altima or sentra gears working in our trannys (VQ atleast).
Best highway cruiser is an Auto, simple as that, but things could be worse, could have extra cylinders with a less efficient engine.
best bet, buy a lightened flywheel for better economy and more fun. Granted you cant justify spending $350 to get better mileage, but you also have to determine how much fun you want to have with the car.
Underdrive pulleys help out too!