Roller rockers are expensive. So are cams, headers, intakes, throttle bodies, electric water pumps, heads, gears, and so on. Stock rockers are pretty durable. You will read about the guys on this and other sites who have stockers that break and spit out the rollers into their engines. And it is true that the stock ratio is 1.7, however, it is a variable ratio and as the rocker is initially lifted by the cam it begins working at a much lower ratio. On the other hand, there are rockers that will begin to work at a higher ratio right off the seat and revert back to the 1.7 ratio - like the Crane Gold rockers. It all depends upon what you want to accomplish when it comes to any modification you may undertake. You just need to make sure you have a plan and the parts you buy fit the plan. Look in the parts for sale section. Over and over you see someone saying "I bought this but it doesn't work for me so now I'm selling it". If you want to know whether or not the 1.8's will work for you, find someone who has what you have and has the 1.8's or has had them. Me, I haven't had any experience with the stroker engine like yours and higher ratio rockers. I just have higher ratio roller tip rockers with stock CID.