I was wondering if a stock HEI can handle an aftermaket multispark unit like an MSD or whatever? Or would that fry the stock module and coil?

any help greatly appreciated hometowns....Ctown

 

It's a bad investment. The stock HEI setup is a great system for up to 400hp while keeping less than 10:1 compression. If you've got more hp, more compression, and are running a cam/intake that's moved the powerband to a peak hp above 6000rpm then get a hotter (more voltage) coil. Then if you're running some anti-street cam, race gas, race everything THEN get a CNP (coil near plug) or COP (coil on plug) ignition system that's like the LS1's and similar truck motors. All it takes is some creative equipment and you've got a CNP setup for under $600, depends on where you get the actual coils and where you get a 96' truck vortec 350 distrib (has a cam position sensor). Then you need the EDist which will run the coils on your car , this is the best upgrade, don't waste money on the MSD stuff unless it's just a hotter coil upgrade.