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although i dont own any of these type of car (scaly viper , tvr400 etc) and was wondering about the pros and cons of the layout? also what other cars run this configuration?
 

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Premium Member
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I understand there is more chance for movement in the bearing for the output shaft.

My two 1955 Le Mans cars have this layout and the Jaguar D Type has had to be returned as it was very noisy and slow out of the box compared to the Mercedes 300SLR.

On the plus side I like the authenticity if the layout and I suppose it might put a little more weight over the pick up preventing certain types of deslotting.
 

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Prof I T
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hi
interesting thread as i have a couple of these cars and will be trying them mag free on a routed track i am building...

Would of thought that having all the weight down the centre of the chassis would result in a better handling car,,thats my theory anyway,,, am i right or wrong.????
 

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Without mags they are very average runners. Can be made to work but will never be as good as sidewinders.

cheers
rick1776
 

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You'll find plenty of threads talking about plastic chassis cars saying NSR and Slot it cars are way quicker than the brands that have front engines.
You'll find plenty of threads saying how metal chassis cars are way quicker than NSR and Slot it cars.
If what they are saying is correct, you can't help noticing the quicker stuff isn't front engined.
Somebody like to tell us some reasons for that??
 

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There are lots of things that combine to give you a final result. There is no magic bullet to take a line from JFK's assasination.

For magnetic cars its faily simple. For a given magnetic downforce with all other factors kept constant, the lighter car will always win. Hence the battle to always produce the lightest car. Hence the use of large anglewinder motors with large mag downforce for "non mag" plastic racing etc.

In an ideal world using physics 101 a front engined car should be the go, but its not. In line motors suffer from undesirable torque reactions and procession through corners which lessens or increases the effective grip at the rear of the car depending on whether you are turning left or right. A sidewinder suffers less from these two effects.

The traction force at the rear wheels is F= u x m x g Increase the mass and you increase the traction. But wait its not that simple. Increase the mass and you increas the centripetal force as well. So its a neutral sum game right? No its not as the coefficient of friction, u, is not a constant but varies with the change in mass. There is a sweet spot where u is maximum. Whats the maximum u? Depends on the tyre and the track surface you race on. Ive found it for the tyres and track surface I race on and so I build my cars with the a weigth bias to suit. Front motored cars will nearly always need more weight at the back to get the appropriate traction force being developed. But then there is all this weight at the front that is not necessary but its not like you can remove it, right? So you end up with a car that is heavier than its sidewinder equivalent.

So there are two reasons why a front engined car is generally slower. Im sure there are more reasons. And Im sure there are people that have front engined cars where that car is blindingly fast.

cheers
rick1776
 

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Motor in the front increases the opportunity for chassis flex....of which every plastic chassis I have seen has to some degree.
Eliminate that,add some body float as well as some traction and you might be able to do OK.
 

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Nobby Berkshire
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Front motor cars with either a good magnet or weight at the back have always been faster for me with Fly and Scalextric cars on a comparative basis. On the other hand, sidewinder cars (especially Scalextric) and anglewinder cars (especially Ninco) tend to suffer from tailswing and record much slower times because you can't push them hard around challenging corners. But they are more entertaining to race around challenging circuits as you have to be on the ball to stop them from falling over their own feet at every opportunity. The only exception to this are SlotIt and NSR cars as they make the effort to give you grippy tyres that reduce tailswing.

But as people have said, if you race without magnets they are not so hot and you have to compensate with more weight at the back to keep your tyres on the track.
 

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Bill Beggs
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My Scaley Viper has the bearing glued in and runs on Slot.It S2 tires on wood. It runs very well. Back end sticks. I would buy another. Now the sound is something else. I swear it seems like it is going to puke it's gears at any time but it just keeps running.
 

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Tom Brown (Scorpus Flex)
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i had a scaley corvette that had a front mounted motor and it was brilliant. I had a little extra weight in the back and glued the shaft holder bit in place, had some MJK tyres on it. the problem is when the cheap motor eventually starts to die its more difficult to put a slot.it in one in there.
 

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Tore
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My experience is with plastic cars (scalex, ninco, scx, carrera, slot.it, NSR etc...) raced without magnets on mostly permanent painted Scalex Sport, but also Classic/SCX track and recently unpainted Carrera track.

Front motor cars without magnets will always have a handicap against inline/SW/AW setups. The handicap comes mostly from weight distribution and vibration from the drive shaft. I've found that if you build cars to a specific set of rules, the front motored cars usually end up about 10 grams heavier than cars with the other configurations, due to the need of adding extra weight low and rear in the chassis to compensate for the far forward and high CoG weight of the front motor.

Vibration is the second enemy, a slightly out of round drive shaft spring will shake the rear end so badly that the vibrations continue all the way to the tires which then start to behave like untrue tires even when they are true, which again translates to reduced grip.

But this does not mean that front motored cars has to be bad runners. With a reasonably straight drive shaft, the right tires and the right amount of lead in the rear they are great runners and often more forgiving and more fun to drive, they just clock in a couple tenths slower than the other cars if they have to follow a set a rules that limit power, tire width, etc...

Tore
 

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Just like 1:1 cars, front motor means the weights in the wrong place and you lose power due to the prop shaft, BTW I hate plastic chassis anglewinders like Nincos, from an engineering point of view they are just wrong, BRSCA anglewinders are closer to plastic sidewinders than they are to plastic anglewinders, and my NSR Porsche 917 runs at a small angle despite most people referring to them as sidewinders.
 
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