How Fast Should I Drive It?

[lepic56]

I found an article about the eternal question,  How Fast Should I Drive It?,  especially for the younger collectors..     Interesting in the way ours engines are built compared to others brands..

.Plymouth First Decade: How Fast Should I Drive? (ply33.com)

 

[TodFitch]

I think I read that a while ago.

[Plymouthy Adams]

basically, what is the posted speed limit....most folks stay off the interstates and with that....the posted limits for MOST areas will be fine...

[keithb7]

Interesting read. I agree. 50 mph in my 3spd non OD ‘38 Plymouth is comfortable and gives me a bit of peace of mind if there were an accident. Or a deer were to jump in front of me.  It seems that at age 50, my perspective has changed. I weigh safety a lot higher on my scale than I used to at 25. Being able to increase my odds of living thru an accident ranks quite high.
 

 50-at-50. Seems like a catchy phrase for my old Mopars. Lol. I will use that in the future. 
 

Added anxiety comes from impatient drivers tailgating and showing aggression. I like to minimize this by driving on 4 lane hiways if possible, if I am leaving town. Or 2 lane hiways at first daylight. Summer months, the roads are pretty dang quiet at dawn. 
 

Yet my ‘38 Plymouth maintains 90% driving time as a in-town cruiser. Coffee or ice cream gatherer. Showing off at 25 mph and being the center of conversions often.

 

[Plymouthy Adams]

Tailgater and folks on the cell phone.....last week I was sitting behind this guy at a stop sign, blamo he backs right into me....jumps out of the cab still talking on the phone telling the guy he will have to call him back......so distracted driving is by far the worse case scenario.  BUT also in the very rural farming area I live one must also watch the other guy as you never know when they going to cut left when you are passing as they never look behind them or signal their intent because in their mind, they still on the tractor in the field.  We lost the horse to the tractor for sure, but the blinders were kept and put on the operators.

[Sniper]

Interesting, so much for my plan to see if this sucker can do 90

[keithb7]

I woke up at 3 am and the answer hit me. "How fast should I drive it?"

 

100 then subtract your your current age.  Using this formula your current age also represents your chances of survival in a crash at calculated speed.

 

You are 20. Max speed 80 mph. Chance of survival 20%.

You are 80. Max speed 20 mph. Survival rate 80%.

 

?

 

 

 

Edited March 11, 2022 by keithb7

[Plymouthy Adams]

you need to have your car to where it will keep up with the traffic you may encounter on the roads you drive else you are a risk to all, if you cannot feel safe with that speed in that car, repair it as needed or park it or flat out burn it to the ground.   I love seeing old cars out and about, abhor old cars that can't meet the test of the road or drivers will not drive as the situation demands, if they or their car is not up to perform, you need to stay at home and invest in a trailer.  Get real folks...I am not saying don't drive your car, I am only saying don't add to the problems of traffic during peak traffic times and such.

[Sniper]

PA makes a good point here.  Just because your car can do 65 on the highway doesn't mean it's smart idea to do it without considering the whole picture.  One of the reasons I added discs to my Cambridge. so that when that clown in the left lane decides, always at the last second and maybe a few seconds past that, to zip across three lanes of traffic to hit the off ramp I have the brakes to keep from smacking into him.  of course great brakes with skinny tires is a waste of money so fatter tires go on.  Then steering effort goes up and you consider power steering, the snowball is rolling now.  All of that matters not if you are unrestrained inside the vehicle, so seat belts get put in, etc.

 

To date, I have have the Cambridge on the highway once, got on got up to 65, got right back off at the next exit.  Too much wobble in the front end, so the suspension gets gone thru, kingpins rebuilt, etc.   

[Bryan]

In the 70s my 71 Camaro would be hard to keep from wandering at 110 mph.  Kept it below what felt unsafe.  I only did top speeds with my Yamaha RD 350 2 stroke in Germany on sunny, no wind days with little traffic on the Autobahn.   45mph electric bike with bike brakes..few hundred feet kept in front in case I had to stop. Even people sitting on a side road I'd slow up just in case.  Always drive according to the vehicle's capability, road conditions, time of day, traffic, your health and mental alertness, etc.  Can also add the difficulty in fixing what you're driving.  Crashing a new Toyota Corolla fully covered by insurance is a lot less painful than smacking a 48 Dodge with hard to find expensive parts.

[Merle Coggins]

Drive it like you stole it... ?

Or, just keep you foot in it so you don't get run over by Michigan traffic on I-94. 

[Adam H P15 D30]

I run 65-70 comfortability with my 49, mostly 65.  Everyone else around me is running 80+ bumper to bumper in their Teslas.  Have to use the 4 lane super slab to get anywhere so I just stay to the right and don't let it bother me.  Kind of like Keithb7, the older I get the less I give a s__t about what the other drivers think, they can go around.  Commute time is always 'interesting' around here in an old car running 65 in a 65 zone with everyone else whizzing by. 

Adding front disc brakes and modern rear drum brakes is not an option if you want to drive where I live.

Edited March 11, 2022 by Adam H P15 D30

[Dan Hiebert]

I think each of these old cars and their respective drivers have a sweet spot, which may evolve over time (read; as the driver ages).  Different for everyone/each car.  Our D24 and I have one for "highway" driving right at about 50, 55 on good roads (which are far and few between up here).  Car sounds good, handles well, rides nice, not too much wind noise, etc.  Just plain old...comfortable.  We each have different ideas of that comfortable.  

 

In TX and NM, we didn't live near an Interstate, in MI I avoided the Interstates like the plaque, even when driving a new car.  When we lived near Buffalo, NY, I had the Dodge on the I-190 spur on occasion since that was the only way to get onto Grand Island, where my office was.  Never "had to" get over 50 for those short stints.  Only ever had the ol' girl on a wide open Interstate once, which was here in Maine for 26 miles, cruised nice at 60 but was just getting a tad too noisy for my liking.  That was on bias-plies.  I'll take it for an Interstate jaunt with the radials just for giggles this year, otherwise, no reason to get it on the Interstate for local driving.    

[YukonJack]

I don't know about anyone else, but I have no desire going 75mph in my 75 year old car. 

[TodFitch]

40 minutes ago, YukonJack said:

I don't know about anyone else, but I have no desire going 75mph in my 75 year old car. 

Nor do I have any desire to try to go 89 MPH in my 89 year old car.

 

I did get it up to 70 MPH once. My more usual top speed is between 50 and 60 MPH.

[Plymouthy Adams]

by these assumptions...one would go faster walking if they have a fairly late model car....forget that!!!!!

[SteveR]

On 3/10/2022 at 8:12 PM, keithb7 said:

50-at-50. Seems like a catchy phrase for my old Mopars. Lol. I will use that in the future. 

What happens when you reach 60? 60 at 60 is also a catchy phrase but could lead to,...well,....best not talk about that,

I'm 70 next year. 70 at 70? Whoo-Hoo kinda gets your heart pumping. I didn't know my 37 could go that fast!... Hmm,... Or maybe 70mph is the speed they take you to the hospital at.

[SteveR]

11 hours ago, TodFitch said:

Nor do I have any desire to try to go 89 MPH in my 89 year old car.

My first car was a 1965 Barracuda with a 225 slant 6, 13" bias-ply tires. I wondered if it would do 100mph. I was 19years old. So on a country road in northern Minnesota at 12 midnight off I went. I made it to 105mph when I shut her down. I was feeling quite proud of myself and never thought twice of the consequences of my stupid actions.

[Mikec4193]

With all my old heaps that I have driven...50 to 55 is about it...I did once get my 1968 VW up to 65 mph and it had a feeling that I was about to take off...

 

Had a 1947 Willys CJ2A and that liked to run about 35 to 40...anything over 45 and things got really squirrely..

 

I even had 1953 Chevy truck once...that was flat footed at 53 mph even with 4.10 gears in it...

 

Old and slow

 

MikeC

[Adam H P15 D30]

Just a question for those not comfortable at speeds over say 50...  Is it you or is the car squirrely, engine too busy?

I consistently run 65 sometimes 70 or even some sprints to 80 and its a 2 finger on the steering wheel affair, very stable.  I understand the "I just don't want to" crowd but some of these responses elude to the car's capabilities or being a handful.  For me it's the lack of OD that keeps me at 70 or below for long periods.  With proper gearing or OD they'll cruise at 80 all day...  Just asking

[Sam Buchanan]

Even though it goes against many of the impulses I've demonstrated in my experiences with motorized devices, I think more now about the implications of physics that Mr. Newton explored a few years ago. If my P15 is brought to an abrupt and complete stop at 70mph there is four times the amount of energy to be dissipated than if the stop occurred at 35mph. The primary way the old car can shed that energy is by totally and catastrophically compressing and/or sending bits and pieces in multiple directions. Of course my body will still be following Mr. Newton's implications and attempt to continue its current trajectory at 70mph. The p15-d24 forum will have one less subscriber.

 

In spite of all that, I really enjoy cruising my '48 between 50-60mph (with a seat belt), but I try to drive with the same mindset I used many years ago while piloting motorcycles!  

Edited March 17, 2022 by Sam Buchanan

[keithb7]

Adam what year is your car? Model? Engine size? Stock tranny and type? Crown & pinion ratio. Tire size and type? Bias? Radial? Brakes stock or upgraded?  Stock worm gear steering? 
 

It all makes a difference on the car’s capability and comfort (risk) level for the driver. 

 

Stock brake systems with skinny stock bias tires on my 1938 stock Chrysler feels a whole lot different than my ‘53 stock Chrysler with 265 ci engine and wide balloon radial tires.  ‘38 aerodynamics and the center of gravity sure is tons different than my ‘53 also. 

At the time 15 years difference was more like 40 years worth of engineering improvements. 

[Adam H P15 D30]

41 minutes ago, keithb7 said:

Adam what year is your car? Model? Engine size? Stock tranny and type? Crown & pinion ratio. Tire size and type? Bias? Radial? Brakes stock or upgraded?  Stock worm gear steering? 
 

It all makes a difference on the car’s capability and comfort (risk) level for the driver. 

 

Stock brake systems with skinny stock bias tires on my 1938 stock Chrysler feels a whole lot different than my ‘53 stock Chrysler with 265 ci engine and wide balloon radial tires.  ‘38 aerodynamics and the center of gravity sure is tons different than my ‘53 also. 

At the time 15 years difference was more like 40 years worth of engineering improvements. 

Since you're asking, I am using my 49 as the example...  Stock 230, except for intake/exhaust changes, stock front suspension with 1 coil cut and no shock relocation, disc brakes, late model rear axle with 3.0 R&P, 235/60/15 rears, stock 3spd FD.  

You're right and wrong about improvements over time, 38-39 there were many improvements to the chassis, 39 to my 49 and later, not much changed.

I drove a 40 Ford PU for many years and miles up and down California at 65-70, all stock buggy sprung beam axle suspension.  Stock 59AB, 3spd with OD and no issues except the occasional overheat in traffic.  Point is, it can be done and done comfortability.

I was only asking if it's a personal choice or some cars were incapable and in need of repair?

Yes, if you wreck one of these cars it will probably kill you but I'll take the trade off and not worry about what could happen.  I'm 49 years old and not 25 so I do take less risks but there are limits to what I'll give up...  Gotta live a little to stay young.

[FarmerJon]

Saw a motorcycle vs car wreck yesterday- both 40mph or less, rider in very bad shape....life is full of risks, best to have your affairs in order. 

 

By the math of the article, my P15 should be OK to cruise at 67 (3200rpm) to 71 (3400rpm) with reserve up to nearly 80mph. Only one Highway near me has a speed limit of 70, not sure many areas have limits higher than that. 

My car is nearly stock, except dual exhaust and aerostar springs, but needs the mount rubber replaced under the steering box, and passenger side suspension rebuilt, a alignment, and likely wheels need a better balance job. 60 is comfortable, although I have to watch myself, I try to shift "up" into second looking for the next gear....

65-70 wheel balance starts to have some shake, and it feels too light for my taste. I suspect once my suspension is sorted it will feel confident up to the limits of the engine. 

 

[Dan Hiebert]

Our D24 just gets too noisy for my liking.  I was told once by a Forum member that if I thought it was noisy at 60, drive it at 70 for a while, then it'll seem quieter at the lower speeds.  It handles well enough and has enough power to probably do 70, but it wasn't engineered for that speed.  I'm thinking of doing a minor rebuild in the next few years, more towards making it even more drivable, disc front brakes, more insulation, clean up the wiring, etc., nothing for more speed.  Don't get me wrong, I have no problem driving fast...in cars that are engineered for it.  Put me back in a police package Charger, and watch out!