#6 will be fine, a #6 is rated for higher amps than a #8 so you wont have any issues, you can always upsize wire but never downsize wire. Just like the hot tub probably could have use the #8 but because of the voltage drop from the length of the wire #6 was used. #6 THHN is good for 75 amps as long as it doesnt pull 75 amps or more you will be fine using #6 and if you are still nervous about it call a local electrician.
dclydeg86 t1_ir1p2g7 wrote
Reply to Wiring EV Charger by Loon610
#6 will be fine, a #6 is rated for higher amps than a #8 so you wont have any issues, you can always upsize wire but never downsize wire. Just like the hot tub probably could have use the #8 but because of the voltage drop from the length of the wire #6 was used. #6 THHN is good for 75 amps as long as it doesnt pull 75 amps or more you will be fine using #6 and if you are still nervous about it call a local electrician.