I just got done watching a great show about the Pebble Beach Concours de Elegance. One of the cars they talked about was this... The 1959 Ferrari 412 S Now, before someone reports this thread for being OT, I'm making a reference to the set of guages it had. It featured 5 guages. One of which was a nice big tachometer, sitting in the middle. NO speedo, just that beautiful, big tach. I thought that was a pretty cool deal. I mean, when I'm driving, I glance at my speedo to check how fast I'm going, but I wondered how cool it would be to just use the tach. As much as I like the idea, I probably couldn't do it because I use the odometer to calculate my fuel level. When I get to about 150 miles, I know I have 3 gallons left and it's time to fill up. I'm also sure that tire size, gears and engine modes come into play. So, how practical is this for a street car? Would it even matter in a car with an auto-trans? How many of you use a tach with no speedo.
I had an O/T car (pro street '71 model) that had no speedo. I engraved a mark on the tach at the rpm where I was running 55 mph (measured against a friends car and confirmed with GPS) I based everything off of that one mark and it worked well.
If you've never "driven by tach" you must be a youngin'. Ha Ha! I've done it! No it's not spot on accurate, but you get close enough not to get a ticket. I guess the best way to describe it is that there's a lot of "being one with your car" going on.
On my old Touring I never finished up the speedo cable and ran it by the Tach all the time I had it. Not sure if GV ever fixed it? The OD in my daily makes it harder to do but I watch the Tach as much as the Speedo because it is underpowered and needs to be in the powerband (higher revs)
I've yet to have a car with a working speedo. If running just the tach you could write you ear mark speeds at certain rpm's on a piece of paper until committed to memory.
I ran a 71 Gremlin off the tach on the 2010 Hot Rod power tour. About 4000 mile round trip. I had a sheet with rpm and mph values on the dash. Nick
Same here and if they did work, it wasn't for long - I use a GPS hung off my WS, remember the tach readings at speeds/gears, and you're done ....
I've had a broken speedo (& working tach) for years. No problem. I usually stick with the speed of traffic & I'm OK.
. My new deuce coupe will have 3 guages in a panel in the stock dash. 1. Oil pressure 2. Tach 3. Coolant temp Keepin' it simple. .
I seldom use a speedo for anything but the odometer and I actually had a trip odometer one thime with no speedo. if you know your car or your bike you don't need a speedometer.
Or a map. Before there was anything that even resembled a GPS I criss crossed this country on an ol beat up motor cycle, no speedo or tach. I had a 150 mile cruising range and I could use a map and road signs to make sure that I didn't run out of gas. Something else you can do in a car that is a little more difficult on a bike is carry a can of gas. When I used to make the run through Blyth it was 200 miles without service, I used to find an old jug of some sort and carry a gallon of gas with me. Normally ballanced on my lap. In a car or a pickup I could have put it in the floorboard or the trunk or the bed. This is going to stir some of the fellas up but it is good time for all of you to learn to live without modern convenience and really experience life a little bit. There is a lot of life to live out there and it can and should be experienced by using your brain a little bit.
I've got a Model A Tudor that I built in the early '80's. Been driving it without a speedo now for close to thirty years. I've put a lot of miles on it and only got one speeding ticket and that was my fault. I missed seeing a speed limit sign.
geez i am probably older than a lot of u and drove truck for 20+ years ,but i drive by the seat of my pants , never far off .
For the 25 years I've had my 27 I have been to lazy to hook up the speedometer. I just use the tach. Every 1000 rpms is 20 mph in high gear.........so 3000 is 60 mph. My 23 didn't have speedo or tach, I just drove a little slower than traffic and never had a problem. Don
all you "drive by tach" guys try driving onto a school zone guessing where 25 MPH is while a cop is pointing the radar at you and kids running around.. you would need to mark your tach with the speeds in each gear. might be easier with an automatic, but I wouldn't want to be in that situation with a stick shift. I like my speedometer.
I drive through a school zone every morning with just a tach, and 5 speed, its not that tough. For the first 2 years i had the truck done i didnt have either, not really that hard. Only been pulled over once and i knew i was speeding.
I was going to drive through a school zone once. Only ticket I ever got in a school zone was in a Blazer with a speedometer. 45 in a 25, @ 3 AM. I think a speedo is a good thing especially if you are a Lexus generation driver, but I don't think that you need to have one of you can drive and know your vehicle.
Funny you should bring this up. Way back before the inter-web, I remember reading ( Hot Rod Mechanix, maybe 12 Port News) some different references to hot rodders setting up their gear ratios so that at highway speeds, they were "half-taching the speedo", 3k rpm was 60 mph, etc. This was back before overdrives were as commonly used as they are now. At the time, I was driving an '83 VW GTI, which was kind of a hot little fwd sh!tbox. In 4th gear at highway speeds, the tach read right at half of the speedo. Later, Kinky6
Just what I was thinking. Was trying to remember if I've ever owned a "real" car with a functioning speedo...
In my Dodge, 2800 RPM is 80 mph. One night, the speedo cable broke, so the tach worked for me. I fixed the speedo cable immediately, though. A cop isn't going to buy the story "But, Officer, I was only doing 3200 RPM!"
Yep, before those new fangled Over Drive things became popular, we always set up street/strip cars that way - RPM = 1/2 MPH in top gear. It made the best compromise of speed, acceleration and high speed cruising.
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