Have very well maintained HP500 has 200 hours ,at 150 hours heads were trued, all rebuilt,valve springs and retainers were changed etc.
Used Fel-pro 17048 head gaskets !
If i put a blower on with 5-6 psi ,do i need to change head gaskets again?

Thanks

No, you will be fine. Just keep an eye on the water pressure. Don't let it get much above 25 psi. Cometics would be a better choice, but in your case the Fel Pro's will work just fine.
Eddie

who's head bolts did you use?

I used Felpro Marine head gaskets on my 525SC with almost 8# of boost and they were fine.

I really don't remember,but it was what Teague Marine suggested.I'll look into it more and make sure they are ok.

Thanks Guys

like eddie said you should be fine,,as long as you have arp head bolts or studs..