Engine additives

I have a 84 Caprice sedan w/305 and 74 Catalina 6 door w/455. They both have relatively low mileage but i was wondering about engine additives. I know real preventative maintanence is the best but do any of those additives at the auto parts store really work? If so which ones? Which ones should I stay away from? The same applies to fuel additives.

Thanks

Ive had pretty good luck with that Lucas oil additive, if your engine takes five quarts you put four quarts of regular oil and the 5th quart of Lucas oil

i was looking at the lucas oil this morning at advance auto...so it is really good to use? what exactly does it do?

supposedly it quiets noisy insides (such as lifters i belive) slows oil leaks and stops exhaust smoke, from what the bottle says anyway. I used it on my last oil change and i noticed somewhat of a difference but i probably wont use it on every oil change, being as how expensive it can be too

ok i may need to invest in that..my duals have been smoking something serious..my carb is tuned up..oil is in the car..but my pipes still blow like a blackish/blueish smog...hopefully this lucas stuff helps

yeah it did for me, i was getting some smoke out the driver side pipe

Ahh, mechanic in a can.
Some say don't waste your money on them but they can work for some problems.
I have used Rislone in the past on a car that was only driven short distances at a time.
I was wondering about z-max. They make a lot of claims and spend a lot on marketing but does the product work as advertised?
Does anyone have any feedback on this product?

Lucas is nothing but thick oil and I have seen proof of it foaming in a manual transmission. They have a HUGE advertizing budget and from the analysis of the "oil" I have seen no R&D budget to speak of. If you think it is useful just use a thicker oil.

z-max was sued by the ftc, is not really anything more than mineral oil and dyes, more garbage.

There are a few good additives out there BUT you wont find them at many parts stores. Most parts store stuff is really simple basic stuff, a lot of the fuel system cleaners are just kerosene or paint thinners of some sort.

AutoRX is a genuinely good engine oil additive. Lube Control has good oil antioxidants and fuel system treatments. Shaeffer's oil has some good fuel system stuff too. This stuff is all much harder to get ahold of than walking into the average parts store, and cost more than that stuff too but that is because R&D costs more than advertizing. Sadly R&D does almost noting for sales because the American public is so feeble minded they buy NAME before results.

A HUGE number of big name companies make garbage, Fram comes to mind, worst oil filter money can buy but easily the biggest seller and most available. All advertizing, no quality to backup the name.