I've had quite a few hp 500 intakes in my hand. Only brass in them has been the thermostat itself. Some dual plane 365 mag intakes had brass inserts though.

Have one in my hands as we speak. give me somewhere to send you pics

the intake on my hp500 has no brass lined coolant passages.that may be different for different year models,idk.

I have brass lined Merlins for my motors. I'm not saying they never made one just that they aren't common and that dart doesn't currently produce a brass lined single plane.

Do the 500 and 525 efi's have brass lined just curious because because I am thinking of maybe putting one on my 548 Merlin tall deck and using a procharger. Are the manifolds short or tall deck,and if short will I be able to use spacers. This is just a thought. Also thinking about super charging roots type. At any rate they are aluminum intakes and not cast iron right?

If I recall correctly the HP 500 started in model year 1994 or 1995 - I am not saying all the intakes had the brass liners but certain runs did and can not remember what years per those runs plus how many of them. I understand that Dart does not brass line anymore period as they have a hard anodized coating. Just saying, I never said all the intakes were brass lined. Merlins had the brass liners agree with that.

Pretty sure they are both standard decks. 525 would a better setup I think. Aluminum yes.