Rev counter in track - who's smoking what at lotus

VL3X

Moderator
Staff member
Joined
Aug 18, 2021
Messages
3,141
Reaction score
4,819
Location
Delaware, USA
Here's to hoping there will be updates that owners can easily flash themselves. I'm still disappointed there's no analog style option. If I can get user customizable faces on my smart watch, I don't see why it's not possible for the Emira.

BTW, here are some other digital speedos from the past... None seem to do the weird compression at the beginning and end of the rev ranges like the Emira does.


 

Johnson

Emira Fanatic
Joined
Nov 19, 2021
Messages
441
Reaction score
666
Location
Tasmania, Australia
That “boost %”… does anyone know what that’s reporting? I know with turbos it’s either estimated boost pressure or spindle speed, but how does it work with a supercharger? As it’s directly connected to the engine, does it just track linearly with the RPMs (so 100% at 6800)?
 

VL3X

Moderator
Staff member
Joined
Aug 18, 2021
Messages
3,141
Reaction score
4,819
Location
Delaware, USA
That “boost %”… does anyone know what that’s reporting? I know with turbos it’s either estimated boost pressure or spindle speed, but how does it work with a supercharger? As it’s directly connected to the engine, does it just track linearly with the RPMs (so 100% at 6800)?

Good question. I think these Edelbrock superchagers only add ~7-8 psi... Maybe that % gauge is somehow reporting volumetric efficiency?

 

CHEESE

Emira Fan
Joined
Jan 23, 2022
Messages
203
Reaction score
244
Location
NJ
Good question. I think these Edelbrock superchagers only add ~7-8 psi... Maybe that % gauge is somehow reporting volumetric efficiency?

It's probably exactly what it looks like: real-time boost as a percentage of maximum boost. If max boost is say, 8 psi, then it probably shows 50% at 4 psi, for example.

Personally, I'd rather see boost as psi on the gauge, but I may be biased.
 

TomE

Moderator
Staff member
Joined
Aug 10, 2021
Messages
6,427
Reaction score
14,630
Location
Surrey, UK
Emira Status
Emira on order
That “boost %”… does anyone know what that’s reporting? I know with turbos it’s either estimated boost pressure or spindle speed, but how does it work with a supercharger? As it’s directly connected to the engine, does it just track linearly with the RPMs (so 100% at 6800)?
I think it's % of maximum. If you watch the video of the chap trying to do the 0-60 test in the yellow Emira (which is a V6 s/c), the boost figure varies between 0 and 100 in a way that tallies with what you'd expect the s/c performance to look like.
 

DaaS

Emira Fanatic
Joined
Aug 3, 2021
Messages
452
Reaction score
804
Location
USA
Emira Status
Emira Owner
For when you miss a downshift and over-rev the engine. You can then see 8 and 9 light up 💥
 

EspritGuy

Emira Addict
Joined
Aug 14, 2021
Messages
1,817
Reaction score
2,468
Location
DFW
Emira Status
Emira Owner
I have an EV that charges at the front. There is no arrow. If one don’t know where your charge port is, then one shouldn’t drive.

i guess the same reason your GTi goes to 180 mph..... supposing it wouldnt ever make it no?
But it makes it look good and you feel like its worth a try... haha
Aspirational....
 

CHEESE

Emira Fan
Joined
Jan 23, 2022
Messages
203
Reaction score
244
Location
NJ
But maximum what? Spindle speed? Pressure coming out of the supercharger? Or volumetric efficiency? Each one requires a different type of sensor…
In the context of forced induction, boost generally refers to pressure. This would be pressure post-source, so somewhere between the source and the head(s).
 

dgrace

Emira Fiend
Joined
Oct 10, 2021
Messages
788
Reaction score
1,591
Location
WA, USA
Here's to hoping there will be updates that owners can easily flash themselves. I'm still disappointed there's no analog style option. If I can get user customizable faces on my smart watch, I don't see why it's not possible for the Emira.

BTW, here are some other digital speedos from the past... None seem to do the weird compression at the beginning and end of the rev ranges like the Emira does.
The framerate and responsiveness on that Audi R8 digital dash is excellent. I suspect the Lotus is going to disappoint on those factors based on what I've seen from current reviews. If they'd send me an SDK I'd be happy to code up a set of analog-looking guages.
 

Porter

tap tap... is this thing on?
Joined
Aug 6, 2021
Messages
2,520
Reaction score
4,513
Location
DC/Virginia, USA
Emira Status
Emira Owner
I'm going to be the weird one and say that this is a really interesting approach to a classic problem... digital bar tachs are somewhat non-ideal to use on track because there's a ton of the bar that's not actually used when in normal track driving rev ranges. At least with a round tach you can prioritize the important range across the top of the tach, but with a bar graph there's no natural way to highlight a range without adding clutter to the display. So this solution is interesting.

When trying to pick up information from your lower peripheral vision, the brain can process left-right color and motion ok but it needs to be relatively big motions to register well. Small fine movements are less visible if you aren't staring directly at the screen. So in this display, they've expanded the middle of the rev range to get more detail to the driver because the movements are over a greater space at the rpms that are being prioritized. Nobody drives at 2200rpm on track, so that range is deprioritized - the engine wakes up somewhere around 4k and redline is just below 7k, so that's the range they've stretched to get the longest "sweep" out of it that they could. The bits that are compressed at the left and right ends are areas that you wouldn't be using on track anyway, so why dedicate space.

It would have been helpful if they had actually highlighted the zone to show what they were doing, it would have improved the visual understanding of the scale change and show intentionality.

Something like this, I've accentuated the bar with dark blue in the stretched section from 4k to 7k:
1656385653751.png
 
Last edited:

digilotus

Moderator
Staff member
Joined
Nov 12, 2021
Messages
1,909
Reaction score
3,868
Location
Australia
Emira Status
Emira Owner
I'm going to be the weird one and say that this is a really interesting approach to a classic problem... digital bar tachs are somewhat non-ideal to use on track because there's a ton of the bar that's not actually used when in normal track driving rev ranges. At least with a round tach you can prioritize the important range across the top of the tach, but with a bar graph there's no natural way to highlight a range without adding clutter to the display. So this solution is interesting.

When trying to pick up information from your lower peripheral vision, the brain can process left-right color and motion ok but it needs to be relatively big motions to register well. Small fine movements are less visible if you aren't staring directly at the screen. So in this display, they've expanded the middle of the rev range to get more detail to the driver because the movements are over a greater space at the rpms that are being prioritized. Nobody drives at 2200rpm on track, so that range is deprioritized - the engine wakes up somewhere around 4k and redline is just below 7k, so that's the range they've stretched to get the longest "sweep" out of it that they could. The bits that are compressed at the left and right ends are areas that you wouldn't be using on track anyway, so why dedicate space.

It would have been helpful if they had actually highlighted the zone to show what they were doing, it would have improved the visual understanding of the scale change and show intentionality.

Something like this, I've accentuated the bar with dark blue in the stretched section from 4k to 7k:
View attachment 7030
Great post - your rationale is pretty spot on I think! I still feel that a more elegant solution would have been to use a logarithmic scale (as per my prior post) which would achieve the same outcome in a more elegant way.
 

xen

Emira Fanatic
Joined
Jan 18, 2022
Messages
461
Reaction score
640
Location
U.A.E
I'm going to be the weird one and say that this is a really interesting approach to a classic problem... digital bar tachs are somewhat non-ideal to use on track because there's a ton of the bar that's not actually used when in normal track driving rev ranges. At least with a round tach you can prioritize the important range across the top of the tach, but with a bar graph there's no natural way to highlight a range without adding clutter to the display. So this solution is interesting.

When trying to pick up information from your lower peripheral vision, the brain can process left-right color and motion ok but it needs to be relatively big motions to register well. Small fine movements are less visible if you aren't staring directly at the screen. So in this display, they've expanded the middle of the rev range to get more detail to the driver because the movements are over a greater space at the rpms that are being prioritized. Nobody drives at 2200rpm on track, so that range is deprioritized - the engine wakes up somewhere around 4k and redline is just below 7k, so that's the range they've stretched to get the longest "sweep" out of it that they could. The bits that are compressed at the left and right ends are areas that you wouldn't be using on track anyway, so why dedicate space.

It would have been helpful if they had actually highlighted the zone to show what they were doing, it would have improved the visual understanding of the scale change and show intentionality.

Something like this, I've accentuated the bar with dark blue in the stretched section from 4k to 7k:
View attachment 7030
I think this is a classic case of a solution in search of a problem.
 

Porter

tap tap... is this thing on?
Joined
Aug 6, 2021
Messages
2,520
Reaction score
4,513
Location
DC/Virginia, USA
Emira Status
Emira Owner
I think this is a classic case of a solution in search of a problem.
I think having the first half of the bar be useless information on a tachometer when you're only varying between 4k and 6.8k rpm to be a legitimate problem. With a simple linear scale, the Zero to 4k section is bigger than the 4k to 7k, shifting the whole of the "used" rev band to the an area half the size, on the right hand side of the display.

This is a legitimate approach to the "put the important info central" ethic of dash layout design. Remember, this isn't the car's standard tachometer, it's absolutely specific to the Track Mode. It's giving the driver a centralized display of the most important information that they need in that limited context.
 
Last edited:

Eagle7

Emira Aficionado
Joined
Nov 20, 2021
Messages
2,754
Reaction score
5,597
Location
United States
Instead of having a bar that's the same brightness its entire length, they could make the edge of the bar bright, and about the width of the leg of the letter N in that image, and the rest of the bar be only half as bright, since it's just filler. Basically a subdued grey while the hotspot is bright white. The important graphic is the hotspot as it moves. Your eye would pick up it's position and movement, instead of the entire bar standing out.
 

TomE

Moderator
Staff member
Joined
Aug 10, 2021
Messages
6,427
Reaction score
14,630
Location
Surrey, UK
Emira Status
Emira on order
I'm going to be the weird one and say that this is a really interesting approach to a classic problem... digital bar tachs are somewhat non-ideal to use on track because there's a ton of the bar that's not actually used when in normal track driving rev ranges. At least with a round tach you can prioritize the important range across the top of the tach, but with a bar graph there's no natural way to highlight a range without adding clutter to the display. So this solution is interesting.

When trying to pick up information from your lower peripheral vision, the brain can process left-right color and motion ok but it needs to be relatively big motions to register well. Small fine movements are less visible if you aren't staring directly at the screen. So in this display, they've expanded the middle of the rev range to get more detail to the driver because the movements are over a greater space at the rpms that are being prioritized. Nobody drives at 2200rpm on track, so that range is deprioritized - the engine wakes up somewhere around 4k and redline is just below 7k, so that's the range they've stretched to get the longest "sweep" out of it that they could. The bits that are compressed at the left and right ends are areas that you wouldn't be using on track anyway, so why dedicate space.

It would have been helpful if they had actually highlighted the zone to show what they were doing, it would have improved the visual understanding of the scale change and show intentionality.

Something like this, I've accentuated the bar with dark blue in the stretched section from 4k to 7k:
View attachment 7030
Good assessment. We don't know the specifics of the Lotus thought process on it yet, but this is sufficiently different from standard that you'd hope they've given it some coherent thought rather than just done it on a whim. Your explanation fits with a driver-focused display, which I know the HCI team have been very passionate about creating.

I expect a similar exercise has resulted in the fuel and temp gauges running outwards from the centre rather then both going left to right.
 

VL3X

Moderator
Staff member
Joined
Aug 18, 2021
Messages
3,141
Reaction score
4,819
Location
Delaware, USA
I expect a similar exercise has resulted in the fuel and temp gauges running outwards from the centre rather then both going left to right.

I'm sure we'll get used to both.

Aston's analog speedo/tach gauges were a unique experience for me.. how they moved in opposite directions from one another. I'm also used to rpms traditionally being on the left side (or dead center).

 

xen

Emira Fanatic
Joined
Jan 18, 2022
Messages
461
Reaction score
640
Location
U.A.E
I think having the first half of the bar be useless information on a tachometer when you're only varying between 4k and 6.8k rpm to be a legitimate problem. With a simple linear scale, the Zero to 4k section is bigger than the 4k to 7k, shifting the whole of the "used" rev band to the an area half the size, on the right hand side of the display.

This is a legitimate approach to the "put the important info central" ethic of dash layout design. Remember, this isn't the car's standard tachometer, it's absolutely specific to the Track Mode. It's giving the driver a centralized display of the most important information that they need in that limited context.

Problem, and a legitimate one at that, to whom exactly? Which race driver / formula 1 designer / reviewer has complained about a tach being too linear and would rather an arbitrary scale unique to one particular car that’s different from every other car they’re driving?

Yes I understand the rationale…it’s is a solution but one to a problem nobody has.
 

Similar threads

Top