XRAY - Model racing cars

What is the best Servos to use for the NT18

Hitec HS82mg
Multiplex Digi Polo

And I have ordered a new Hitec: HS5084mg

Is that the same servo for throttle and steering?

It is what you like to spend.....

The Hitec HS81 has some issues which are taken out with the HS82 servo.
For steer you must use a metal gear servo (mg) but if you want to save money you can use on the throttle a servo with plastic gears, the HS8x comes in both versions. I believe the Xray XS01 servo is based on the HS81mg.

If you like colors then Multiplex has nice red servo's. The Tiny-S with plastic gears, the Tiny-MG with metal gears and the Digi Polo which is a digital servo.

All mentioned until now have almost the same specs with a speed of about 0.1 sec@60 degrees and a power of about 3kg-cm

A newcomer on the market if you do need speed is the Hitec HS5084 with a speed of 0.05 sec@60 degrees but 2/3 of the power as the others which should be ok, the speed is only usefull if you are running on short tracks and it is digital.

With some radio systems you do need digital servo's, the later models of KO and the Futaba HRS do use a higher framerate which analoge servo's can not follow.

Just look arround if you can not find any of the mentioned, any micro size servo with the specs close to the HS81 will do.

Thanks for the info.