Your grill grates can reach a temperature of 700 degrees Ferenheit in about 40 minutes. We've seen temeratures has high as 800 degrees with just the four main burners on high. The side sear burner on our grill islands can reach a max temperature of 600 degrees, with no other heat sources, in about 30 minutes. The rotisserie burner can reach a high of 300 degrees in about 30 minutes without the help of other burners.