Chapter 3, Measuring for the New Engine

Motor:

With the old engine out it is time to measure and find out exatcly what can fit in the space between the gearbox and the wheelcover. You can gain a little extra space by trimming the wheel cover. But be aware you don’t want to interfere with the wheels and if a part of your motor is sticking in there you got to develop some way to protect it against grime thrown from the wheels.

I figured that there was about 40 cm from the edge of my gearbox to the wall of the wheel cover. That is not much but I still got fair amounts of motors to choose from. I picked a 9" Kostov motor: The motor is 24 Kw and got switching stator field; meaning that I can change its configurations: See the diagram on the drawing above. so I can choose between high torque and high Rpm. which can help me economize my battery power during different driving condition.

In comparison the original two stroke petrol engine is 19.1 Kw so I definitely expect the new engine to improve its overall specifications.

Generally electric cars got better acceleration than fuel cars of same motor size, because they have a high peak output. eg mine has a peak of 100 Hp meaning that it can give an output of 100 Hp for a shorter time on the maximal rated power. However after a short time the power output drops to its continuous 31.7 Hp. A peak output in some form can be reached from all currents given to the motor.

Try squeezing 100 Hp out of a 31 Hp gasoline car :-)

Of cause you cant squease all that power out of the car if you don’t have batteries which can take the Amps the motor is sending back but that is a concern I will deal with later on when I write about the battery pack.

Adaptor :

Okay you cant just replace a cars engine with another like if they were Lego bricks, Because the gearbox is made to exactly fit one or a few types of motors.

To make it fit you have to make an adaptor plate fitting the motor to the gearbox. You will also need to have a torque adaptor connecting the power shaft of the motor to the shaft of the gearbox.

The nice people from Kostov Motors are making a custom adaptor plate for the motor :-) so I dont have to machine one or find a workshop to do it.

I just needed to do the drafting explaining how I wanted the thing to look. Then they send me a cad drawing for me to check if the measures are right: I have completed the order and I am now only waiting for the reply from Kostov Motors explaining that my motor is done and ready to be shipped.

Untill then take a look at this electric car utilizing its peak preformance to beat mucelcars on the drag race strip:

http://www.youtube.com/watch?v=pd9hDa-JHZ8