Depends on gearing
Because of its 645 hp engine
[object Object]
25-40
The engine will run to the limits of it rpm (revolutions per minute). The go-cart will travel as fast as the gearing and torque of the motor allows. Theoretically, you could get a nitrous kit for an 8hp lawn mower engine and do a one-time burst to like 50 HP and maybe 100 mph, before the engine exploded and your go-cart disintegrated. One of my sons manged to get his go-cat up to 66 miles per hour using a 12hp Tecumseh motor from an old lawn tractor. Scary, very scary, but very fast. The neighbors called the police.
Autolite 258
7,2 dl.
.030 inch ( on my 24 year old 5.0 horsepower Tecumseh engine )
It will go about 40 to 50 mph
Depending on if your engine has a restriction or a set speed, you can go as fast as 55 to 65 miles a hour.
about 25-30 mph
50 miles per hour