I haven't found any recent posts on this topic, so I'm starting a new one in this category. I would like to know if anyone has any personal experience with oil additives (STP, Lucas, etc.), and if so, which they liked or didn't like.

Back in the late 60's, a good friend of mine was running a '58 Chevy in F Gas with a pretty stout 327. Every two or three weekends, he would tear the engine down and find that the main bearings needed to be replaced. Because he also owned a service station, a representative of STP suggested to him that their product could reduce or eliminate that problem; that is, he would have to change the bearings less often.

All things being equal - no fresh line boring or crank truing - he found that he could go an entire season on the same set of bearings after adding the STP at the manufacturer's suggested ratio. Having sat in on several tear-downs, I can personally attest to this being true.

So, before anyone ridicules the notion of real "car guys" adding Motor Honey to their cars to keep them from smoking, I'm asking this because things have changed more than a little in the intervening 40 years.