DOHC for 99CVPI

I recently saw a pair of 4.6l DOHC heads for sale, anybody know if it is a direct bolt on, or do I need to reprogram the ECM for them?

chances are they will bolt right up, but you will also need a new intake, injectors, mounting brackets for various items, MAF, PCM, etc. Might even need a different timing cover, but I havent seen one up close to compare.

Nope, they will not work without MAJOR modifications to the vehicle including a new front cover.

Supercharge it instead.
http://www.superchargersonline.com/product_detail.asp?PartNumber=V4FL218-130S

With a little modification it can be made to fit the vic.