[spl310]

Has anyone used the scrapers made by Ishihara-Johnson? The reason that I ask is that they used a couple of my engines as models for some of their units (not Ford engines), and gave me some samples. I even got one for the small block Ford that I have on the stand in the garage. If you used one, what do you think? Is it worth it to install these? They claim some pretty impressive results from this simple bolt on. Is it too good to be true?