Home Racing World

I was talking to someone a few days ago and saying how I thought I was leaning towards liking to run cars with <15k rpm motors, instead of those with more powerful motors. He replied that was probably because of the scale speeds that you get with the smaller motored cars; somewhat more realistic when compared to 1:1 cars than with the larger motored cars. He said that small motored cars run about 200 scale MPH, whereas the large motored cars can run about 600 scale MPH.

Food for thought, but I wasn't sure that I bought it, because the big motored cars don't feel like they're going 3 times faster than the small motored cars.....................

So, I did a quick calculation and came up with the following:

On my track, a good time for a car with a <15k motor is 7 sec. My track is about 60 ft. long.

60/7 = 8.57 ft/sec x 60 = 514 ft/min x 60 = 30,857 ft/hr / 5280 = 5.89 MPH x 32 = 187 MPH

A fast time for a big motored car is 5.5 sec.

60/5.5 - 10.90 ft/sec x 60 = 654 ft/min x 60 = 39,272 ft/hr / 5280 = 7.43 MPH x 32 = 238 MPH

So, there's really not that much difference on my track between a small and a big motored car; in terms of scale speed; about 50 scale MPH; about a 30% speed differential. Would be interesting to see how the speed differentials break out on a straight drag strip, where I would expect to see the largest speed differences.

Anyone else have any experience thinking about scale speed and the cars that you like to run best?

Allan

Allan,

While motors with lesser RPM ratings are easier to drive, I very seriously doubt if they are running 200 MPH.

You stated that your track is 60 feet per lap and that a good lap takes 7 seconds.

If we divide 60 / 7, that says that you are running a true 8.57 feet per second. In 1:1 scale that would be about 10 MPH.

In my opinion, you can not scale MPH or Time up or down.

Im not big on stats, nor math either for that matter. But wouldn't you have to scale that 8.57 ft down to 1/32 scale as well?
I like the smaller motors for what I would call scale "feel". I like seeing the cars, and de slots are far less damaging to my fragile little overly detailed cars as well.
This is probably one of those whatever you like the best topics. some like lightning speeds, and others like less.
Just my two cents.


Bob

But at 1/32 scale, 1 foot equals 32 feet so the perceived speed is up around 200.

In our 1:1 world, the toy cars are going about 10 mph, but if we could shrink down to 2 inches tall and stand at the edge of our slot layout while a slot.it Porsche 962 screamed by at full song, it certainly wouldn't seem like 10 mph :)


Sent from my iPhone using Tapatalk

I just like to see them. It's hard enough for my old eyes when there are similar colored cars.
Wouldn't be the first time I've watched a similar car on the straight , while I deslot in a corner.
Of course I find the variable power supply a great asset in finding a comfortable setting.
Bob

It's like many things in our hobby. From tire preference to with or without magnets.

Some like them blurry, some don't. :)

What's going on? I've tried twice now to enter my opinion on the subject. Which is basically that speed doesn't scale on a straight line.

For me it is all about perspective and feel. I think my scale model of an 800 hp Can Am car should drive differently than my scale model of a 125 HP Ford Escort saloon.

I have a Scalectric white Mustang that will haul the mail around my wooden track in about 4.944 seconds at a scale speed of 210 mph. After I achieved this feat the car unexpectedly launched off my track. One thing this does cause is the Grandsons are now trying to beat Varoomphas time and speed. The timing was done by my trackmate while I measured the lane distances and put that into the trackmate software. I know the measurement was accurate for I used a high quality Harbor Freight measuring wheel. Anyway the main issue I see with the Scale MPH is that it adds to the family competition in a very fun way unit the grandsons beat Varoomphas time and speed. :)

The hard part is for us old guys to put that much body english into the moment like we used to do while playing with the pinball machine. I still can't figure out why we do it for it really doesn't change the direction of the slot car or the steel ball.:)

Bob and Marty, if you're uncomfortable with scaling speed, then let's try size. Size certainly scales in a linear manner, if it didn't we wouldn't have 1/32 scale cars to run/race.

So, if a 1:1 mile is approximately 5280 ft, then a scale 1/32 mile is 165 ft.

My tiddler motored (<15k rpm) cars will cover my 60 ft track in approximately 7 seconds. At that rate, they'll cover a 1/32 scale mile (165 ft) in about 19.25 seconds.

At that rate, they're traveling 0.052 1/32 scale miles/second. Times 60 seconds, that's 3.11 scale miles/minute. Times 60 again, that's 187 scale MPH.

So, whether we scale time or we scale distance, we end up in the same place; somewhere in the neighborhood of 200 1/32 scale MPH.

I'm not a math guy, I'm just looking for the reason that I prefer to race the slower motored cars; after all, I enjoy building the larger motored cars! :lol:

Allan

Allan,

I'm with "The Boss" on this subject. It's all a matter of personal preference.

However since all of us are trapped in a 1:1 world, those cars are NOT going 300 MPH. Yes, you can scale distance, but NOT speed nor time.

Trust me, I've brought cars with me that are extremely fast. Back when I was racing in Florida's My Series, one of our categories was Group 12. I have turned sub 2.0 second laps on a 155 feet per lap "King" track. That is fast by most standards.

I am having more FUN running slot cars at 8 to 12 FPS now.

My opinion says that having FUN is just so much more important.

I don't disagree with the have fun aspect for one moment. It's all about having fun for me. :banana-dance:

I was just surprised at how little scale speed difference there actually is between the slower motored cars and the faster motored cars; that was the point of my original post, not the scaled speed, just the speed differential between the slower motored and the faster motored cars. For me to have as much of a preference for racing the smaller motored cars, I would have expected a bigger scale speed difference than 30%. After all, I was figuring it was my inability to react quickly enough to the faster motored cars that was making me prefer racing the smaller motored cars.

Think I'll put the topic on hold, perhaps someday I'll find my answer..........

Allan

If you are running without magnets, a lot of that "faster" is burned up in wheel spin without as much gain in speed than one would expect.