Well alot of people have used it with good results.

But me personally...not really a big fan of the stuff. Just my .02 cents.

 

Seafoam gets mixed results. If you really want to clean the secondary ports and IMRC's then pull the intake and do it the right way. Index the crank to where the secondary valve is all the way shut. Spray some carb cleaner and grab plastic tooth brush or something long and go to work. Then suck it out with a wet vac. Then clean the IMRC's with carb cleaner or delete them all together. I did this on my car and I could tell a difference. on the big end.

-Mark