[89IROC&RS]

well, i admit i dont know any flowdatta on the 305 heads, but i would imagine they arent very good, and baised on my experience with engines, i will continue to assume that they are door stops untill proven otherwise. the price argument for the 305 vs vortec heads is moot, where would you get the 305 heads?? junkyard more than likeley, so if your at the junkyard already, why not find a wrecked 99 tahoe or something and yank the R code heads off it. same price, and the vortecs flow more air than bowtie heads with the same size valves. to me its a no brainer. but eh, im not gonna change the wold, just give yall the info and let you decide what to do with it.