SR5's are carbed . 3A-C or 4A-C . There not great but can be worked on . Easiest thing is gonna be a 4AG swap that'll net you 100rwhp instead of 60 . YOu need hte gas tank as well since the carbed cars use a mechanical fuel pump and diff tank .

It will still be "driftable" stock . I wouldnt recomend it but it'll do it .