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Tfoster100

Tfoster100

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Jun 26, 2015
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Display name:
Tim
I was making a long xc drive in my truck - 7 hours - wishing I was flying instead. And noticed I was doing a scan of my instruments as though flying. Just not enough to scan though fuel-speed-oil-temp. Made me laugh to myself when I realized what I was subconsciously doing. :D
Guess I need to add a six pack of gauges to my truck for driving. Anyone else ever do that?
 
Just wait until you start to yell 'clear' before starting your car or mower.
 
I still do the race car scan in my street vehicles. I quit full time racing in '92, and raced part time until I hung up the helmet for good in early '95 to take my first flying job.
 
I hate rental cars without gauges. And I won't buy cars that have only idiot lights. ;-)
 
denverpilot said:
I hate rental cars without gauges. And I won't buy cars that have only idiot lights. ;-)
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But, Nate, those gauges don't always tell the truth. It seems some folks didn't understand that oil pressure varies with engine RPM. The engineers thought the cure for that is a gauge that doesn't move but stays in one place as long as there's oil pressure and only goes to zero when there is none. DOH! "Idiot light plus".
 
Zeldman said:
I still do the race car scan in my street vehicles. I quit full time racing in '92, and raced part time until I hung up the helmet for good in early '95 to take my first flying job.
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Same here, only I wish my street cars had all the gauges rotated so that "good" is needles up. :)
 
Half Fast said:
Same here, only I wish my street cars had all the gauges rotated so that "good" is needles up. :)
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Just one more thing i don't like about glass panels. The altitude is always right there, whether you're at 9000, 9500 or 9268 msl . . . You gotta read and understand the digits being shown.
 
Tfoster100 said:
I was making a long xc drive in my truck - 7 hours - wishing I was flying instead. And noticed I was doing a scan of my instruments as though flying. Just not enough to scan though fuel-speed-oil-temp. Made me laugh to myself when I realized what I was subconsciously doing. :D
Guess I need to add a six pack of gauges to my truck for driving. Anyone else ever do that?
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Just don't drop the flaps on final. Especially if you drive a Piper. And two notches for a short launch isn't a good idea.
 
When I get in cars without oil pressure and temp, volts, read outs I get annoyed.
 
Norman said:
But, Nate, those gauges don't always tell the truth. It seems some folks didn't understand that oil pressure varies with engine RPM. The engineers thought the cure for that is a gauge that doesn't move but stays in one place as long as there's oil pressure and only goes to zero when there is none. DOH! "Idiot light plus".
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Yeah I know. They lie. I learned about this on the Dodge. This oil pressure of a diesel at start scares people so the gauge lies for a little bit until it stabilizes. Then it shows the real reading.

The oil pressure gauge on my Yukon doesn't lie. And it's doing some interesting stuff lately. But it's all high. Really high if I rev it hard on the road.

And then there's "Oh I can get all this data from OBD" and then you realize you can't. And the manufacturer made the data proprietary to get from only their scan tool.

And then smart people reverse engineer away the ass-hats who did that. Haha. Thank goodness for determined hackers wanting access to the sensors they bought and paid for.

I haven't looked recently but I hope Nebraska passed their law banning Caterpillar from locking the tractor maintenance data away.

Many farmers were already using hacked code to get their data anyway from a vendor in a former Soviet country (ironic) anyway, at a tenth of Cat's price after the warranty ran out, but "right to maintain" is becoming a bigger and bigger thing.
 
What bugs me most about auto gauges is the speedometer.

Why the hell does the speedometer on my 1.3 litre 4-banger sub-compact hatchback go up to 180 mph? The difference between 65 and 70 mph is the width of the needle. Every new car is like this now. My minivan also goes way up, I think 160.

If they had the ability to switch to km/ph that'd make sense but no...
 
labbadabba said:
What bugs me most about auto gauges is the speedometer.

Why the hell does the speedometer on my 1.3 litre 4-banger sub-compact hatchback go up to 180 mph?
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Fast and Furious? LOL. ;-)

I always figured 120 was to keep the 60 MPH mark dead center straight up for symmetry/ergonomics, and marketing purposes. "It'll go faster!" Didn't want to make it look like redline was at 100, if you could even get there without going down a hill. Haha.

180 in a four banger doesn't make any numerical sense at all.
 
Car dashboards are a major pet peeve of mine. They're designed for idiots

James331 said:
When I get in cars without oil pressure and temp, volts, read outs I get annoyed.
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Pretty soon all you will get is a happy or sad face emoji based on your emissions... yes this is a real journal study, after I read that I left my lights on all day

denverpilot said:
Oh I can get all this data from OBD
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Thank goodness Toyota didn't lock theirs. I love my scangauge. No one else understands why I need to know MAP and MAF while getting groceries. But in reality watching the temps when four wheeling brings me peace of mind since apparently the freaking temp gauge that came with the car stays squat in the middle anytime blthe engine is between 150 and 230. Which is just dumb, 230 is way too hot and too late to take notice
 
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Norman said:
But, Nate, those gauges don't always tell the truth. It seems some folks didn't understand that oil pressure varies with engine RPM. The engineers thought the cure for that is a gauge that doesn't move but stays in one place as long as there's oil pressure and only goes to zero when there is none. DOH! "Idiot light plus".
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With these you lose trend data, and that's not good. You don't know you're overheated until you're overheated. Isn't that a Yogi Berra quote?
 
labbadabba said:
What bugs me most about auto gauges is the speedometer.

Why the hell does the speedometer on my 1.3 litre 4-banger sub-compact hatchback go up to 180 mph? The difference between 65 and 70 mph is the width of the needle. Every new car is like this now. My minivan also goes way up, I think 160.

If they had the ability to switch to km/ph that'd make sense but no...
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Got a tach?

Some cars use the same instrument movement for the tach and the speedo to reduce cost.

The tach sender is at the input shaft for the tranny and the speedo is on the output. Take a look at the two needles when you're in a 1:1 gear (usually 4th) and you'll notice they're at the same deflection angle. If the tach redline in top gear would result in 150mph, that will be the max value on the speedo even if the car has no chance of reaching it.

Top gear is usually a pretty steep overdrive for fuel economy, so redline in top would be very fast if HP was enough to get there.
 
Half Fast said:
Got a tach?

Some cars use the same instrument movement for the tach and the speedo to reduce cost.

The tach sender is at the input shaft for the tranny and the speedo is on the output. Take a look at the two needles when you're in a 1:1 gear (usually 4th) and you'll notice they're at the same deflection angle. If the tach redline in top gear would result in 150mph, that will be the max value on the speedo even if the car has no chance of reaching it.

Top gear is usually a pretty steep overdrive for fuel economy, so redline in top would be very fast if HP was enough to get there.
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I have a tach, and no, the needles aren't synched. It's just dumb.
 
Half Fast said:
Got a tach?

Some cars use the same instrument movement for the tach and the speedo to reduce cost.

The tach sender is at the input shaft for the tranny and the speedo is on the output. Take a look at the two needles when you're in a 1:1 gear (usually 4th) and you'll notice they're at the same deflection angle. If the tach redline in top gear would result in 150mph, that will be the max value on the speedo even if the car has no chance of reaching it.

Top gear is usually a pretty steep overdrive for fuel economy, so redline in top would be very fast if HP was enough to get there.
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I haven't seen that trick since the physical tach cable to the dash days or at least a direct electronics path for pulses with no micro between the sensor and dash.

With everything computerized now, multiplication or division of the sensor output or similar is just handled in the microcontroller to display whatever the automaker wants for deflection angles and what not, on the dash.

Heck, many dashes don't even have physical needles anymore, just graphical depictions of needles on an LCD display.
 
labbadabba said:
What bugs me most about auto gauges is the speedometer.

Why the hell does the speedometer on my 1.3 litre 4-banger sub-compact hatchback go up to 180 mph? The difference between 65 and 70 mph is the width of the needle. Every new car is like this now. My minivan also goes way up, I think 160.

If they had the ability to switch to km/ph that'd make sense but no...
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My Outback has 160 on the speedometer. Wishful thinking..??
 
Bill Jennings said:
You don't know you're overheated until you're overheated.
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Yup. That's why, especially under harsher engine conditions, I like to see the trends of various gauges. Watching a steady decrease in oil pressure, or a steady rise in coolant temp from 183, to 185, to 188, to 190, 192, and so forth will start to worry me. That's the same reason I prefer steam dials for certain gauges vs digital read out, round instruments have more intuition in some applications

Zeldman said:
My Outback has 160 on the speedometer.
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That stopped bothering me once I started interpreting it as Vne. The KIAS on the 172 goes up to 200 even though Vne is 160.. and frankly even 160 would take some effort to hit

GEEK ALERT:
*I do love that in our BMW the cruise control sets a speed bug, what I love even more is that you can set the speed bug with the cruise control armed but not active... when I sit at the ramp red light waiting for the green I get the speed bug dialed up to 72 and then arm the AP/AT, err, cruise control
 
labbadabba said:
What bugs me most about auto gauges is the speedometer.

Why the hell does the speedometer on my 1.3 litre 4-banger sub-compact hatchback go up to 180 mph? The difference between 65 and 70 mph is the width of the needle. Every new car is like this now. My minivan also goes way up, I think 160.

If they had the ability to switch to km/ph that'd make sense but no...
Click to expand...

It's all I how the regulations are written. Speedos must be accurate within a tolerance that Champion gesture periodically, but is a percentage of the maximum value shown. So your car reads to 180; used to be +/-2% or within 3.6 mph; if 2% of your actual speed, it would be 1.4 mph at 70; the old 85 mph Speedos had to read within 1.7 mph all the time. Not sure what the tolerance limits are now.

It's much more expensive to make a speedometer accurate to 1.4 mph than to make one accurate to 3.6 mph. Add a bunch of design dollars, then a few manufacturing dollars for each car made (Honda sells ~250,000 Accords in a year), and you've got big money.
 
Hank S said:
It's all I how the regulations are written. Speedos must be accurate within a tolerance that Champion gesture periodically, but is a percentage of the maximum value shown. So your car reads to 180; used to be +/-2% or within 3.6 mph; if 2% of your actual speed, it would be 1.4 mph at 70; the old 85 mph Speedos had to read within 1.7 mph all the time. Not sure what the tolerance limits are now.

It's much more expensive to make a speedometer accurate to 1.4 mph than to make one accurate to 3.6 mph. Add a bunch of design dollars, then a few manufacturing dollars for each car made (Honda sells ~250,000 Accords in a year), and you've got big money.
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Holy cow. That makes sense. Also sad, really. I usually have Waze up with GPS speed and there's only one speedo in our four vehicles that is close enough to actual speed that you wouldn't get a ticket for driving the erroneous indicated speed. That's the '04 Yukon. The '08 Lincoln LT, '01 Dodge and '00 Subaru are all significantly wrong. One slow, two fast.
 
labbadabba said:
What bugs me most about auto gauges is the speedometer.

Why the hell does the speedometer on my 1.3 litre 4-banger sub-compact hatchback go up to 180 mph? The difference between 65 and 70 mph is the width of the needle. Every new car is like this now. My minivan also goes way up, I think 160.

If they had the ability to switch to km/ph that'd make sense but no...
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My '68 Bug (when I was in college) pegged at 80. It took a good downhill to get it there, though.
 
denverpilot said:
Holy cow. That makes sense. Also sad, really. I usually have Waze up with GPS speed and there's only one speedo in our four vehicles that is close enough to actual speed that you wouldn't get a ticket for driving the erroneous indicated speed. That's the '04 Yukon. The '08 Lincoln LT, '01 Dodge and '00 Subaru are all significantly wrong. One slow, two fast.
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Same here ... the truck IGS* 10% fast and the jeep IGS* 10% slow ... or is it the other way around? See why I use Waze? :) I even have a bully dog on the truck and have re-calibrated for new and different size tires ... didn't change a thing. I think it's broke-ish...
 
The speedometer in my 09 Cobalt and the GPS agree at almost any speed. But The 84 Gold Wing speedometer always read way fast.
 
My portable Garmin GPS matches my Jeep's speedometer exactly and is only -1 MPH from my Wife's Focus speedometer. However, I've used it in a company car (also a Focus) on a road trip and it was between 2 & 3 MPH off.
 
gkainz said:
Same here ... the truck IGS* 10% fast and the jeep IGS* 10% slow ... or is it the other way around? See why I use Waze? :) I even have a bully dog on the truck and have re-calibrated for new and different size tires ... didn't change a thing. I think it's broke-ish...
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Haha. My computer on the Dodge also has a tire size setting. It apparently does nothing. I've set it and then bumped it both directions in size and it doesn't change what the dash display is. I think buried in a menu on the computer itself there's a speedo, but I have limited screen real estate and need the other gauges it displays worse than an extra speedo. So the Garmin or Waze handles speedo duty.
 
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