Ok so I just put a can of this stuff through my engine. I have 100,000miles and I suspected my valves were not shutting properly. It didnt take long, I had clouds of something shoot out my exhaust dirt gunk etc. I went for a spin and the butt dyno told me it felt faster. I got to my usual spot, did my usual automatic launch and got to my usual spot were I should be going 60mph and instead I was going 70moh. Thats the same improvement I had from fitting the cams so Ill goin to refit the cams and try it again. Ill also get a timed run when theres daylight. Very happy and for only 8gbp http://item.mobileweb.ebay.co.uk/viewitem?itemId=130956068540