i strongly suggest you upgrade at least your springs now... that cam has too much lift for stock springs they just wont take it... do not wait til you do your heads or you will be sorry... cmon you dont even have to take the intake manifold off to do it.. go to advacned auto parts and get a valvespring compressor, get one of those telescopic magnets, stick the magnet to the valve, compress the spring and take it off... put the new one on, put the retainers and all that shit in and decompress.. do that for all 16.. better than floating a valve