Never used it on a sxs but had it on a few cars. I agree with these guys that as long as you do your homework and set it up right you should have no problems. If you cant pull timing with it i would def run high octane and go a step or two colder on your spark plugs and gap it accordingly. Id say a 30 shot would be just fine, maybe even a 50hp shot but id start small and jet up and check plugs as you go.keep an eye on bottle pressure , and fuel pressure. Both will affect your jetting.