Q:

What wattage heating element required for 500 degree Celsius oven temperature

i have 32 litres OTG oven which is of 2000 watts and can generate Max. 250 degree Celsius .
40 Litre capacity
2000 watts

OTG has 2 heating elements, one at top and one at bottom. so each heating element is of 1000 watts, when i am on broil mode only 1000 watts heating element is used which is upper heating element, so it takes a lot of time to cook food and i am planning replace it with high watt heating element.
replacing with this one
3000W 220V heating element.

ref: heating element
i am trying to achieve high temperature ~ 500 degree Celsius and quicker, as food i am trying to prepare needs faster high temperature.
i have few questions regarding the same .
1) Replacing current heating element with High wattage heating element, will it give me more temperature or same temperature but quicker ?
2) there is thermostat too on the OTG , which has max 250 degree Cesius reading and knob. 
Do i have change that too ?
or need to get the external thermometer.
i am only planning to use it for specific food preparation which needs high temperature.
3) whats is the relation in between watts and heat generated by heating element ?

OTG outer body is pure stainless stell, so i dont think their will be any melting issue or something like that .

update: 
i was under impression that majority ovens can go upto 500 degree celisus, after checking https://en.wikipedia.org/wiki/Oven_temperatures , i have realized the 250-260 is the highest temperature i can get using oven.
i was trying to get same effect of the "Tandoori Clay Oven" here its says it can go up to 480 degree celsius. https://en.wikipedia.org/wiki/Tandoor
e.g.

after reading answers, i think its a bad idea to use current oven for high temperature like 500 degrees.
the above heating element manufacturer said the heating element can reach upto 200 degree celsius even though its 3000 watts.
so does this mean , it can reach 200 degree quicker ?

A:

1) Both. It depends on how the internal circuitry is driving it, which leads to the answer to the second question
2) That thermostat will drive the heating element on and off in order to achieve the desired temperature. So it will only go up to 250C. You'll need to replace the thermostat (as well as related power cables - they likely won't be capable of handling 15A).
3) There is a fairly complex mathematical relationship between the wattage output and maximum heat. There's no simple way to determine this.
It's also worth mentioning that it may not even be possible to drive your oven to 500C, it's possible that more heat will escape than can be added in a given time unit above a certain temperature.
You will also need to consider all of the other implications of having something at 500C, including things like solder melting.

