Six Speed Manual Technique
#1
Samurai Cheese Slicer
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Hey Everybody,
I've seen some posts about shift points and most of the questions and answers have been pretty rudimentary. I'd like to start a conversation about the finesse that is available to the RX-8 6-Speed Manual Trans driver. If this has been covered, and I missed it, please link to that thread and I will add to it.
I've been a 5-Speed Manual driver for over 20 years. When I bought my RX-8 at CarMax, I had only one criteria, a 6-Speed Manual transmission. My choices included the 2004 RX-8 I bought, a few Mini's and a BMW Z4 that was out of my price range.
In my day to day driving, I coast in neutral down and up the Georgia hills. I use high gears early to cruise on a gentle throttle below 3000 rpm. With piston engines, I was convinced that I knew the technology well enough to believe that lower rpms always meant lower fuel consumption. However with the RX-8, I am not certain that it isn't burning more fuel in 6th gear at 2600 rpm than it would at 4000 in 4th gear. I am certain that accelerating quickly in a lower gear is more efficient than a prolonged drag at mid-level rpms.
This is how I am using my 6MT... I'm curious how you are shifting yours.
First Gear:
Most of the time, I just get rolling, 10-15 mph, 2700-3000 rpm.
For my money, I'd rather invest fuel in higher gears.
Unless I'm teaching someone a lesson, I'm not likely to beep first gear.
When I am first at a stoplight on a high speed road, getting on to the highway, or need to move quickly from a stop, I will take it to somewhere between 7000 and Red line. I like dropping it from 7000 rpm into second at 5500, and running that to 9400 rpm when I really need to go-go.
First is for acceleration only. The rpms should always be increasing.
Second Gear:
Second can get you to 65 as easily as 35.
No matter what traffic speed you are looking for, second can get you there!
Second is the easiest gear for me to beep on my daily drive.
Second is my gear of choice in parking lots, and down my residential street.
Second gear offers Hyperspace jumps from 30-50 mph up to 65 mph.
Second gear with no throttle will slow you from 65 down to 30 quickly.
Second can involve some gentle rise, but should typically be rapid acceleration.
Third Gear:
Wow! Third is functional from 25-90!
This is the go to gear when you need to go faster at all but the fastest traffic speeds.
If I want to keep my throttle very responsive in the 35 - 55 mph range, I leave it in 3rd gear. Curves at 6000 rpm in third gear in an RX-8 are about as fun as any driving can get.
In slow-and-go traffic, I will cruise in fourth gear until the rpms get too low, then easily kick it down to third gear for some acceleration.
Third gear can be a drive gear, and is the best gear for high-performance driving at typical street speeds.
Under most circumstances, third is the highest acceleration gear - rpms should be steadily increasing while in third, when they begin to plateau, shift up.
Fourth Gear:
In slow-and-go traffic, fourth gear is like our automatic... it will work at almost any necessary speed from rolling to go-go-going with a gentle right foot.
I love fourth gear in highway traffic - lane changes and safe position transition become effortless. At highway speeds, fourth gear is very athletic.
It has a lot more torque than 6th or 5th, and is available at any highway speed.
For 60 mph and higher acceleration, fourth is a good choice when you do not need 3rd gear's "Hyperspace" effect.
When I am trying to roll with very low rpms, fourth will work just above idle with a really light right foot.
Sometimes, I find myself shifting into fourth leaving my neighborhood at 30 mph to keep the rpms low while warming up.
Fourth is a good cruising gear at 35-50 mph, with room in either direction.
Fifth Gear:
1:1 Drive Ratio Baby!
I use fifth gear a lot to goose the car up the next hill at 45 mph.
Generally with tiny throttle. Otherwise, I use fourth gear and get more.
I like fifth as a cruising gear in traffic, especially with moderate speed changes.
At speeds of 50-70 fifth gear will offer 20% more response and control vs. sixth gear. Most of the time, I prefer the economy of sixth gear, sometimes fifth makes more sense.
Sixth Gear:
Overdrive!!!!
If anyone should ever encounter speeds over 70 mph, on a track, for instance, sixth gear will offer the best fuel economy.![Yelrotflmao Vi](https://www.rx8club.com/images/smilies/yelrotflmao-vi.gif)
I use sixth as low as 40-45 when I am feeling really frugal, but the right foot has to be very gentle, and I am not certain that my low rpms are saving fuel.
Sixth is the ultimate cruising gear.
As long as I don't need to accelerate quickly, sixth seems efficient at lower speeds, and certainly makes sense at higher highway speeds of 55-70 mph.
Generally, I treat gears 1, 2 & 3 as acceleration gears and gears 4,5 & 6 as cruising gears. I don't do a lot of stop and go driving... generally once I get moving, I am getting up to speed and going until my next stop or turn .5 - 2 miles down the country back road.
I rarely use all of the gears in order.
I often coast for long periods in Neutral.
1-2-N or 1-2-3-N is very common.
From a brief or long coast there, I will go into a cruising gear.
Fifth is common if I am just goosing the speed along before returning to N.
Sixth is where I go if I have reached my maximum intended speed and just want to zoom-zoom along.
Fourth is my cruising gear that requires some torque potential, or during heavier traffic.
Are you a driver that never bothers with sixth gear? Or maybe you usually skip 4th & 5th to get into 6th at 40mph regularly. Are there RX-8 drivers out there that really rev first and second gear high most of the time? Is there a more efficient rev range and shift point for cruising in higher gears?
I rarely engine brake. How about you?
It seems that the Renesis will provide a fair amount of resistance when dropped into third or second gear from most traffic speeds.
I usually slow down in Neutral. Unless I am taking curves in third gear.
Is there a sweet spot in the rpm range that provides maximum efficiency?
One person has suggested to me that 3800-4000 ish is a magical place to be.
I've seen some posts about shift points and most of the questions and answers have been pretty rudimentary. I'd like to start a conversation about the finesse that is available to the RX-8 6-Speed Manual Trans driver. If this has been covered, and I missed it, please link to that thread and I will add to it.
I've been a 5-Speed Manual driver for over 20 years. When I bought my RX-8 at CarMax, I had only one criteria, a 6-Speed Manual transmission. My choices included the 2004 RX-8 I bought, a few Mini's and a BMW Z4 that was out of my price range.
In my day to day driving, I coast in neutral down and up the Georgia hills. I use high gears early to cruise on a gentle throttle below 3000 rpm. With piston engines, I was convinced that I knew the technology well enough to believe that lower rpms always meant lower fuel consumption. However with the RX-8, I am not certain that it isn't burning more fuel in 6th gear at 2600 rpm than it would at 4000 in 4th gear. I am certain that accelerating quickly in a lower gear is more efficient than a prolonged drag at mid-level rpms.
This is how I am using my 6MT... I'm curious how you are shifting yours.
First Gear:
Most of the time, I just get rolling, 10-15 mph, 2700-3000 rpm.
For my money, I'd rather invest fuel in higher gears.
Unless I'm teaching someone a lesson, I'm not likely to beep first gear.
When I am first at a stoplight on a high speed road, getting on to the highway, or need to move quickly from a stop, I will take it to somewhere between 7000 and Red line. I like dropping it from 7000 rpm into second at 5500, and running that to 9400 rpm when I really need to go-go.
First is for acceleration only. The rpms should always be increasing.
Second Gear:
Second can get you to 65 as easily as 35.
No matter what traffic speed you are looking for, second can get you there!
Second is the easiest gear for me to beep on my daily drive.
Second is my gear of choice in parking lots, and down my residential street.
Second gear offers Hyperspace jumps from 30-50 mph up to 65 mph.
Second gear with no throttle will slow you from 65 down to 30 quickly.
Second can involve some gentle rise, but should typically be rapid acceleration.
Third Gear:
Wow! Third is functional from 25-90!
This is the go to gear when you need to go faster at all but the fastest traffic speeds.
If I want to keep my throttle very responsive in the 35 - 55 mph range, I leave it in 3rd gear. Curves at 6000 rpm in third gear in an RX-8 are about as fun as any driving can get.
In slow-and-go traffic, I will cruise in fourth gear until the rpms get too low, then easily kick it down to third gear for some acceleration.
Third gear can be a drive gear, and is the best gear for high-performance driving at typical street speeds.
Under most circumstances, third is the highest acceleration gear - rpms should be steadily increasing while in third, when they begin to plateau, shift up.
Fourth Gear:
In slow-and-go traffic, fourth gear is like our automatic... it will work at almost any necessary speed from rolling to go-go-going with a gentle right foot.
I love fourth gear in highway traffic - lane changes and safe position transition become effortless. At highway speeds, fourth gear is very athletic.
It has a lot more torque than 6th or 5th, and is available at any highway speed.
For 60 mph and higher acceleration, fourth is a good choice when you do not need 3rd gear's "Hyperspace" effect.
When I am trying to roll with very low rpms, fourth will work just above idle with a really light right foot.
Sometimes, I find myself shifting into fourth leaving my neighborhood at 30 mph to keep the rpms low while warming up.
Fourth is a good cruising gear at 35-50 mph, with room in either direction.
Fifth Gear:
1:1 Drive Ratio Baby!
I use fifth gear a lot to goose the car up the next hill at 45 mph.
Generally with tiny throttle. Otherwise, I use fourth gear and get more.
I like fifth as a cruising gear in traffic, especially with moderate speed changes.
At speeds of 50-70 fifth gear will offer 20% more response and control vs. sixth gear. Most of the time, I prefer the economy of sixth gear, sometimes fifth makes more sense.
Sixth Gear:
Overdrive!!!!
If anyone should ever encounter speeds over 70 mph, on a track, for instance, sixth gear will offer the best fuel economy.
![Yelrotflmao Vi](https://www.rx8club.com/images/smilies/yelrotflmao-vi.gif)
I use sixth as low as 40-45 when I am feeling really frugal, but the right foot has to be very gentle, and I am not certain that my low rpms are saving fuel.
Sixth is the ultimate cruising gear.
As long as I don't need to accelerate quickly, sixth seems efficient at lower speeds, and certainly makes sense at higher highway speeds of 55-70 mph.
Generally, I treat gears 1, 2 & 3 as acceleration gears and gears 4,5 & 6 as cruising gears. I don't do a lot of stop and go driving... generally once I get moving, I am getting up to speed and going until my next stop or turn .5 - 2 miles down the country back road.
I rarely use all of the gears in order.
I often coast for long periods in Neutral.
1-2-N or 1-2-3-N is very common.
From a brief or long coast there, I will go into a cruising gear.
Fifth is common if I am just goosing the speed along before returning to N.
Sixth is where I go if I have reached my maximum intended speed and just want to zoom-zoom along.
Fourth is my cruising gear that requires some torque potential, or during heavier traffic.
Are you a driver that never bothers with sixth gear? Or maybe you usually skip 4th & 5th to get into 6th at 40mph regularly. Are there RX-8 drivers out there that really rev first and second gear high most of the time? Is there a more efficient rev range and shift point for cruising in higher gears?
I rarely engine brake. How about you?
It seems that the Renesis will provide a fair amount of resistance when dropped into third or second gear from most traffic speeds.
I usually slow down in Neutral. Unless I am taking curves in third gear.
Is there a sweet spot in the rpm range that provides maximum efficiency?
One person has suggested to me that 3800-4000 ish is a magical place to be.
#2
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Most of the time when I am not in a rush I will shift around 3k-3500 rpm and shift up to 6th gear once I get to whatever cursing speed that road is at. Once in sixth I usually sit in unless I have to go below 35mph or so. It seems to work pretty well if you are going for fuel economy since I have been getting between 22 and 23mpg.
I live in Illinois tho with 0 hills so I doubt sitting in 6th down to that low of a speed will work in most places.
I live in Illinois tho with 0 hills so I doubt sitting in 6th down to that low of a speed will work in most places.
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I am not sure if that distance would account for the difference in fuel consumption but it is definitely noticeable.
#5
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i have tested it. start in the highest gear possible then shift down as needed as the speed decreases until you have no choice but to gas it a little or shift into neutral. ill be cruising along in 4th then shift up to 6th and take my foot of the gas to limit the amount of engine braking
#9
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Thanks for the feedback!
@Zoom44 - thanks for the decelerate in gear tip. I will see where I can add that effectively to my drive. I believe I ultimately still save fuel while coasting at idle in many situations, as even 6th gear's drag will cause me to have to accelerate many more times than I do now. I bet there are dozens of places along the way I can drop it in gear and not lose my gravity effect. It will certainly help me when coming to a stop, and at a few corners, where I will experiment with slowing in gear rather than with the brakes.
Can someone clarify this? With the engine in gear and my foot off the pedal, the ECU is feeding NO fuel to the intake? And spark is shut down?
There's not some minimal fuel consumption equivalent to idle at all times when the pedal is at it's neutral rest position? Possibly also metered by rpms? Does anyone have a figure for the amount of fuel a properly warmed stock Renesis consumes at idle? If I rev it slightly above idle while coasting, I'm probably just being ridiculous, yes, but would it burn less fuel than idle? ;-)
If there is near zero fuel consumption with foot off accelerator while in gear, does it matter which gear? Am I as near zero letting it pull second gear at 6000 as sixth gear at 2000 rpm?
I have avoided engine breaking, believing it would ruin my gas mileage.
How is it possible that it could actually be calorie free? I have always slowed down in neutral, only occasionally asking the motor for help.
Fun is making it do exactly what I want it to do, and knowing it can. So far, I am still figuring out some of my 8's personality.
The small percentage of time that I actually have allowed the 8 to perform to its capacity, my car has been very responsive, predictable, and satisfying.
In between those moments, I like to be in the best gear for this hill or curve, and still do what I can to keep the gas stations further apart.
Tomorrow's drive with all of this in mind. Thanks for the great tips!
Can someone clarify this? With the engine in gear and my foot off the pedal, the ECU is feeding NO fuel to the intake? And spark is shut down?
There's not some minimal fuel consumption equivalent to idle at all times when the pedal is at it's neutral rest position? Possibly also metered by rpms? Does anyone have a figure for the amount of fuel a properly warmed stock Renesis consumes at idle? If I rev it slightly above idle while coasting, I'm probably just being ridiculous, yes, but would it burn less fuel than idle? ;-)
If there is near zero fuel consumption with foot off accelerator while in gear, does it matter which gear? Am I as near zero letting it pull second gear at 6000 as sixth gear at 2000 rpm?
I have avoided engine breaking, believing it would ruin my gas mileage.
How is it possible that it could actually be calorie free? I have always slowed down in neutral, only occasionally asking the motor for help.
Fun is making it do exactly what I want it to do, and knowing it can. So far, I am still figuring out some of my 8's personality.
The small percentage of time that I actually have allowed the 8 to perform to its capacity, my car has been very responsive, predictable, and satisfying.
In between those moments, I like to be in the best gear for this hill or curve, and still do what I can to keep the gas stations further apart.
Tomorrow's drive with all of this in mind. Thanks for the great tips!
#11
When I see threads about shifting at a certain speed, I have no clue. I'm looking at the other dial. I could be all wrong, but I don't like running it below 2500 or 3000. Above there, the engine seems perfectly happy and there's a wide range of shift points possible. I do need to clear the piston mentality and get the revs up more for passing. There have been times when I should have dropped down a couple of gears, maybe three, instead of one.
#12
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I usually accelerate in 1st, 2nd and 3rd with about 1/3 throttle up to the speed limit then skip right to 6th for normal everyday driving. I usually shift between 4000 and 5000 rpms.
I usually only beep 2nd gear unless I'm geting on the freeway, then I'll beep 2nd and 3rd.
IMHO, 5th gear is the most useless gear on the 8. They could get another 2-3 mpg out of the 8 if 5th gear was geared like 6th and then 6th was another 500-1000 rpms lower for freeway cruising. If I could change the gearing, I'd make 5th 500 rpms lower then make 6th 1000 rpms lower.
I average 18-19 mpg mixed driving and 22-23 all freeway.
P.S. I love the 6th to 3rd hyperspeed jump.
I usually only beep 2nd gear unless I'm geting on the freeway, then I'll beep 2nd and 3rd.
IMHO, 5th gear is the most useless gear on the 8. They could get another 2-3 mpg out of the 8 if 5th gear was geared like 6th and then 6th was another 500-1000 rpms lower for freeway cruising. If I could change the gearing, I'd make 5th 500 rpms lower then make 6th 1000 rpms lower.
I average 18-19 mpg mixed driving and 22-23 all freeway.
P.S. I love the 6th to 3rd hyperspeed jump.
Last edited by usnidc; 09-28-2010 at 08:31 AM.
#13
Roto-rookie
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![Yelrotflmao Vi](https://www.rx8club.com/images/smilies/yelrotflmao-vi.gif)
#14
Coasting in gear (no fuel injected) is much more effiecent than coasting in neutral - having the throttle shut and the engine idling is one of the most ineffiecent operating conditions of a petrol engine, acceleration is actually quite effiecent as the throttle is open so the engine isn't having to work against a vacuum and therefore the dynamic compression ratio increases.
And you've got a lot more control over the vehicle if you need to accelerate around someone who pulls out on you, etc, as well as the engine braking if you need it to stop in a hurry (no reaction time for engine braking either...)
And you've got a lot more control over the vehicle if you need to accelerate around someone who pulls out on you, etc, as well as the engine braking if you need it to stop in a hurry (no reaction time for engine braking either...)
Last edited by PhillipM; 09-28-2010 at 09:56 AM.
#15
Samurai Cheese Slicer
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Coasting in Gear
OK, So I've driven two days with much more coasting in gear than in neutral.
Two normal days of work drive plus highway trip to and from Midtown, all highway, all at unhindered traffic flow.
Staying in gear almost to a full stop certainly reduced my break pad wear during the test so far.
It seems beneficial when approaching a full stop or some turns.
The engine will begin idling at 1000 rpm, and you can crawl at 25ish in 6th.
Several spots on my drive where being in gear provided additional control in downhill curves without reducing fun factor.
However, I have several stretches of up & down & up & down where neutral will allow me to coast for a half mile or more, but adding downhill in gear almost anywhere requires much more effort to get up the next hill. I'll stick to neutral on these rollercoasters.
Ultimately, I think I can coast in gear about 50% of the time I was previously in neutral.
There wasn't any deviation in today's fuel-up, but I will experiment further.
Additional testing will determine where free-rolling neutral will win out over fuel-conserving yet restraining minimal gear.![Freak Anim](https://www.rx8club.com/images/smilies/Freak_anim.gif)
I will follow the fuel consumption and fun factor and repost.
On the Highway, I kept the rotary revving higher than previous more often today, and didn't get into 6th quite as quickly.
I quite enjoyed driving 4th gear at 4100 rpm at 70.
I read somewhere that the fuel mixture becomes richer to protect the catalytic converter at steady speeds over 4000 rpm.
Can I avoid that by varying my rpms slightly - how little and how frequently?
Two normal days of work drive plus highway trip to and from Midtown, all highway, all at unhindered traffic flow.
Staying in gear almost to a full stop certainly reduced my break pad wear during the test so far.
It seems beneficial when approaching a full stop or some turns.
The engine will begin idling at 1000 rpm, and you can crawl at 25ish in 6th.
Several spots on my drive where being in gear provided additional control in downhill curves without reducing fun factor.
However, I have several stretches of up & down & up & down where neutral will allow me to coast for a half mile or more, but adding downhill in gear almost anywhere requires much more effort to get up the next hill. I'll stick to neutral on these rollercoasters.
Ultimately, I think I can coast in gear about 50% of the time I was previously in neutral.
There wasn't any deviation in today's fuel-up, but I will experiment further.
Additional testing will determine where free-rolling neutral will win out over fuel-conserving yet restraining minimal gear.
![Freak Anim](https://www.rx8club.com/images/smilies/Freak_anim.gif)
I will follow the fuel consumption and fun factor and repost.
On the Highway, I kept the rotary revving higher than previous more often today, and didn't get into 6th quite as quickly.
I quite enjoyed driving 4th gear at 4100 rpm at 70.
I read somewhere that the fuel mixture becomes richer to protect the catalytic converter at steady speeds over 4000 rpm.
Can I avoid that by varying my rpms slightly - how little and how frequently?
#17
I drive at Red Line.
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Two finger shifting works just fine for me. Has plenty of times on the track to. You don't need a lot of strength to seat the gears in the car. If your having to jam it into gear your going to damage the forks. Just use light pressure till it synchros and falls into gear.
#18
If you've match the speeds right it should clack right in with 2 fingers, forcing it anywhere just causes wear and tear.
The only geabox you should should firmly shove into gear are dog or sequential boxes.
The only geabox you should should firmly shove into gear are dog or sequential boxes.
#20
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Coasting in neutral is not legal in Georgia.....
Excerpt:
Other Laws
......................
Coasting
The driver of any motor vehicle, when traveling down a hill, must not coast with the gears or transmission of the vehicle in neutral.
www.dds.ga.gov 51
5/21/2009 1:20:54 PM
From bottom of page 51 of GA Drivers Manual.
Excerpt:
Other Laws
......................
Coasting
The driver of any motor vehicle, when traveling down a hill, must not coast with the gears or transmission of the vehicle in neutral.
www.dds.ga.gov 51
5/21/2009 1:20:54 PM
From bottom of page 51 of GA Drivers Manual.
Last edited by GaZoom; 10-11-2010 at 07:33 PM. Reason: Add reference
#25
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Don't Shoot! I'm Neutral.
Really?
I can understand that coasting in neutral in an Automatic Transmission vehicle,
especially one made prior to, say, 20 years ago, would be extremely dangerous,
and appropriately illegal. If you hit 120 downhill in a 1969 Plymouth in neutral, the brakes wouldn't slow you down due to lack of engine vacuum and the transmission would explode when you tried to pop it back into gear, after your wheels locked up and you skidded off the mountain.
That is nothing like the situation in an RX-8 in neutral.
An RX-8 steers and breaks equally as effectively with the engine in neutral or at redline. Yes, there is some (significant) discretionary control derived from being in gear vs. not in gear, but being in Neutral does not actually reduce the breaking or steering capability.
While in Neutral, I am always only a fraction of a second away from the best gear for whatever situation I am about to encounter... which is a giant leap away from whatever might happen if you drop a 3-speed automatic back into "Drive".
Also, when I transition from a long glide in neutral back into a gear, I use a well practiced clutch/fuel technique to match the revs for a gentle engagement.
My wife lurches more in her automatic than I do while having plenty of neutral fun in my RX-8. Heck, I lurch more in her automatic!
A HELICOPTER following me for my entire journey might be able to correctly determine nearly 50% of my neutral coast moments.
In most respects, even with neutral coasting, my driving is typically smoother than most automatic trans drivers.
I tend to accelerate and decelerate more elliptically, but I am almost never around any other vehicles anyway.
I don't see how being in neutral in an RX-8 vs not in neutral in an RX-8 could be detected, determined, or remotely prosecuted.
I certainly don't see that it is unsafe in any way.
The manual RX-8 is much safer than at least 90% of the cars on the road at any speed, in my opinion - stock, it has superior tires and brakes, and you can put the 6-speed into a happy place at any speed.
I can understand that coasting in neutral in an Automatic Transmission vehicle,
especially one made prior to, say, 20 years ago, would be extremely dangerous,
and appropriately illegal. If you hit 120 downhill in a 1969 Plymouth in neutral, the brakes wouldn't slow you down due to lack of engine vacuum and the transmission would explode when you tried to pop it back into gear, after your wheels locked up and you skidded off the mountain.
That is nothing like the situation in an RX-8 in neutral.
An RX-8 steers and breaks equally as effectively with the engine in neutral or at redline. Yes, there is some (significant) discretionary control derived from being in gear vs. not in gear, but being in Neutral does not actually reduce the breaking or steering capability.
While in Neutral, I am always only a fraction of a second away from the best gear for whatever situation I am about to encounter... which is a giant leap away from whatever might happen if you drop a 3-speed automatic back into "Drive".
Also, when I transition from a long glide in neutral back into a gear, I use a well practiced clutch/fuel technique to match the revs for a gentle engagement.
My wife lurches more in her automatic than I do while having plenty of neutral fun in my RX-8. Heck, I lurch more in her automatic!
A HELICOPTER following me for my entire journey might be able to correctly determine nearly 50% of my neutral coast moments.
In most respects, even with neutral coasting, my driving is typically smoother than most automatic trans drivers.
I tend to accelerate and decelerate more elliptically, but I am almost never around any other vehicles anyway.
I don't see how being in neutral in an RX-8 vs not in neutral in an RX-8 could be detected, determined, or remotely prosecuted.
I certainly don't see that it is unsafe in any way.
The manual RX-8 is much safer than at least 90% of the cars on the road at any speed, in my opinion - stock, it has superior tires and brakes, and you can put the 6-speed into a happy place at any speed.