need some help with selecting cylinder head Mopar 408

98 octane is pretty good compared to what we have here. You should be able to run more than the 10-1 limit we use with alum heads and 91 octane gas. I am guessing that you could run 11-1 with alum heads.

I would suggest contacting some of the engine builders here and discussing a set of Eddys that they buy bare and then set up for your cam and compression. They should be able to make the paperwork seem like the heads were cheaper than the actual cost to help with the VAT, and you will get the springs / valve travel you need for your combo.