Do not ever buy those replacement engine bolt sets.

[TJ Hopland]

Tip of the day.  If you are doing engine work like replacing gaskets and such you may be tempted like I was to buy one of those stainless steel engine hardware kits since they are not that expensive and its a time consuming hassle to clean up old bolts plus stainless should look nice right?

Total waste of time that will bite you in the butt sooner than later.  Those bolt kits tend to be low quality and don't have the built in washer like the factory ones did so they WILL NOT stay tight and you WILL end up with leaks.  Its really bad if you have something like say and FWD Eldorado where you can't access all the oil pan bolts.   

If you are buying from a brand like say ARP you are probably fine just don't waste your time with those generic kits that even the specialty vendors sell. Best option is to just spend the time cleaning up the old stuff.  I'm not talking about things like head bolts here, for those you have to do your research and find out what type your engine is supposed to have.  Some can be reused and others can't.   I'm mostly talking about the bolts that hold the 'tins' on.         

[Big Fins]

Best to put the originals into a tumbler for a few days, then chase all the threads and bolt holes.

Stainless is too soft for many applications anyway.