Curly wrote:
Snake oil perhaps, but for the last 3 or 4 years I've been running an in-line, tin-alloy fuel catalyst on my 998cc, Cooper S headed, Bugeye Sprite. They aren't cheap in the short term, but they are a set and forget option.
This car has been raced, driven in Sprints, hillclimbs, motorkhanas and gets used on the road as well, drinking 98 octane unleaded. The other day I did a routine service which included checking valve clearances, compressions etc and found that most of the rockers needed tightening up a thou or two which is the normal situation with this engine. So unless the cam lobes are wearing faster than the Valve Seat Recession, this head, which hasn't been off since the engine was built in 1998, and the catalyst are staying put.
Head on since 1998, catalyst since 2003/4. You have a good build up of lead, known as "lead memory" on the valve seats etc. This is a proven fact, and you generally will get 60% of the kms you did on leaded petrol (or LRP, to a lesser degree) before the lubricating properties are lost.
I stand behind my snake oil conclusion. I have read the 'how it works' sections, and while it has been 8 years since studying chemistry at uni, their explainations are rubbish, with selective misquotes to lend credence to their scam. For those that notice a difference in fuel economy i say "not in a controlled study you won't", there are too many human factors making them 'get' the result they want.
A catalyst needs to be present in a chemical reaction, it isn't. To lubricate, you need something to be added to the petrol, the 'catalyst' doesn't do this. May as well utter a mayan chant and sprinkle chicken blood over the bonnet. Actually, that may work better.
Use an additive, or get unleaded seats or both.
Or you will get VSR.
Simple.
