Best way to clean exhaust tips

[gldgti]

WD-40 and denim rag.

Then some cheap cut/polish.

Anything you put on there to seal it, so to speak, will bake off in no time really. However, if chrome is nice and clean it will stay clean for longer

[Treza360]

I always find that a little bit of waxing always keeps them shiny for a little bit longer. As Dan said though heat will always be a killer here.
Cheers,
Trent

[Mrk_Mickey]

Sealants are usually a much better option in heated areas such as wheels...that's why wheel wax can't compare to sealants like nanolex and opti seal. I'd go for a sealant on the tips, and for the sake of them being cleaner I'd wipe them down every time I wash the car, and spray more sealant on!