mamoon2

I've decided that i'm going to modify my sons electric car to make it faster and I need the good folks of Scoobynet to help me out.

His 6v car has become a bit slow for him and as I actually sell these cars I could quite easily order a 12v battery and bigger "engine" pack (motor) but I can't see the fun in that.

His standard car is a Ferrari F430 Scuderia as pictured here



It currently has a 6v battery which i'm going to change and also has plastic wheels which i'm going to look at changing to rubber.

Now i'm no electronics expert so I figure I need to change the battery (currently 6v 12ha) for a bigger one and also upgrade the motor.

I've been to Maplin and they do a 12v 12ha battery which I could modify the car to make it fit (its twice the size of the current one) but they do not do motors bigger than they one i've took off the car.

Can anyone point me in the right direction of a more powerful battery 12v/24v which isn't to big for the car and also a motor

Current battery is 150mm x 90mm x 40mm

Motor is 35mm dia / 55mm length with 3mm rod coming out

Also am I right in thinking that just changing the battery will not make the car faster as the motor will need to be upgraded?

The Zohan

Is there nothing a scobbynetter will try to make go faster by modding

Good luck and please post the results

Oh and you need to get your sons hair cut and dress him like a boy, no dresses!

JonsGreenGoblin

I agree, just changing battery will supply more power but only to the same motor, so yes better motor will be a upgrade in speed.

I maybe wrong though, im sure someone else will be along soon to say

AbbasSTI

iTrader: (37)

My nephew has the same & his also is need more power, so good luck & post lots of info here please

Tidgy

pmsl, i;m yet to see something mentioned that no one will have a go at lol

Jer

Get a car battery and an old starter motor.

mamoon2

Right, i've ordered some rubber wheels off eBay so thats one part done.

Now i'm thinking about a battery from a Mobility Scooter as these seem to last longer in between charges and seem to cart "fatties" around at a reasonable speed all day so should be lightening fast with with a 3 stone kid in 15kg plastic car!!

I'm thinking two of these 12v 20hm batteries to give 24v of power

Mobility Batteries

Now i'm stuck on the motor part, so i'm hoping someone will be along shortly to advise

mamoon2

Are these capable of being ran constantly, for say 30 minutes?

Jamo

iTrader: (23)

what about a washing machine motor? get an ac converter and convert the 12v to 240v that should be a little quicker?

Jer

My mate stuck one onto a home-made gokart years ago and it was fine. It went like stink though so may not be sutable for a young kid. The acceleration was mental.

mamoon2

Probably not then

fast bloke

Maplins do a 12v 20Amp 20 AH for about 30 quid. The AH's don't matter too much. That is just how long the battery can produce those amps for. The volts won't make much difference either (more volts will give more torque, but no more speed). You just need to have as many Amps as possible. Next thing to fix is the motor. If you have enough amps, the motor will produce a virtually unlimited speed. My first attempt at modifying the kids electric quad used a heavy duty rechargeable strimmer motor. 18000 rpm is quite quick. After the quad stopped digging tracks in the lawn it probably hit about 40 MPH in 2 seconds. You basically couldn't hold on. Swapped that for a 6000 rpm chainsaw motor. Smaller tracks in the lawn, but you still couldn't hang on. Next was the motor from a hedge trimmer. This worked a treat. The quad goes about running speed, and does that all day.



p.s. - Be careful if you are experimenting. When our first kid was born, she was a couple of months premature. She wouldn't suckle, so the hospital suggested that my wife should get a breast pump, pump the milk and then feed her from a normal bottle so we could monitor how much she was taking. We got one powered by 2 AA batteries, which did the whole keeping the kid alive thing, but the batteries only lasted 3 or 4 days.. I decided that something mains powered would be much better, so after a bit of tinkering with a nokia phone charger, we had a mains powered breast pump. She attached it as normal, flicked the switch, and I looked on horrified as her entire left tit was sucked into the bottle. It only took about 5 more attempts until we found that an Ericson phone charger produce an approprite amount of power

Leslie

You could try a Dawson's Device but you will have to adjust it to avoid overboosting and fuel cut!

Les

mart360

However there is a downside

Newton

for every action, there is a reaction

OK you make the cart go like sh*t of a stick

how are you going to stop it???

Mart

JDM_Stig

iTrader: (3)

YOUR OLD, Think Back to when you made Go Karts, Brakes were the last thing we ever thought about and I cant think of a single Go kart we fitted a brake too lol
Kids need speed not brakes, they only slow you down,
Also the extra torque, will the axle etc cope with it?
Is the motor direct drive or any kind of gearing you can play with?

Kieran_Burns

iTrader: (1)

Entire mouthful of coffee over the keyboard, screen and wall behind!

Quote of the year that one....

StickyMicky

@ the tit suck

belliott69

iTrader: (3)

this a great thread, can't wait to hear how it goes.

ScoobySteve1979

iTrader: (1)

how fast do u want it ?

Kieran_Burns

iTrader: (1)

trying to be serious (and not read the tit comment again), if you want to reduce the speed: change the gearing as a larger cog on the axle and smaller on the motor will produce more torque and less speed

mamoon2

I want a maximum speed of 10 mph.

mamoon2

I'm gonna change the battery to 12v and up the amp's first. I'm hoping together with the new Rubber wheels this should make a difference. If it doesn't i'll look at changing the motor.

My calculations are that for a 19500 rpm (i'm guessing this a about what it is) motor @ 6v the speed is 4.6 mph so if I up the voltage to 12v it should give 9.1 mph. But we will see.

Will post update soon

Richy P1984

You could try altering the transmission - add a larger pinion gear to the comm of the motor, depending on the motor this could give you higher top speed without hurting acceleration too much.

Can you take the motor apart? - if so you could increase the number of wires wound round the comm, increase the strengh of the magnets, replace the brushes (if it isnt brushless) with more efficient ones. You could also re-skim the comm, but thats dependent on what equipment is available to you.

You could also look at upgrading the ESC or replace the manual SC if it has one. Replacing the battery with one that can deliver more 'juice' will help a bit. Used to make a big difference back in the RCC days.

mamoon2

*** UPDATE ***

I took delivery of a 12v 20ah battery made for a mobility scooter yesterday and quickly set about fitting it to the car.

Straight away the increase in power is noticeable! I popped the chief test driver in it this morning for a quick blast and it seems twice as fast but traction is a problem now. It spins the wheels for a second before it picks up some grip.

Next job is to fit the rubber wheels i've just had delivered. These require some modifications to the axle to fit. So i'll pop back with an update when i've done them.

May also have to put the old 6v battery back on to make 18v

I'll get a video up when she is finished

Steve vRS

Now you have the power, you can follow the Impreza tuning bible and fit wheels which are too large and lower it using stiff springs to remove any remaining rude comfort.

Steve

The Zohan

splendid, look forward to the next installment - perhaps this should be moved to projects?

mamoon2

I don't think our liability insurance would cover us for selling modified kids cars

Mataway

Is it possible to replace a 6v battery with a 12 or 24-v one?

Leslie

I used to use an old starter motor on a winch to drag my racer up the ramps into the back of my old 36 seater bus. It coped very well with that so it should have more than adequate power for a pretty fast car for your lad.

Les