[gajagfan]

Originally Posted by Elite Engineering

On any GDI engine these are a must, but the benefits for a port injection engine are also many:


Prevents excessive oil consumption by stopping the residue build-up on rings and in ringlands that can cause piston rings to not move freely.


Improves power by reducing KR due to oil caused detonation (you ONLY want air and fuel present during combustion. Any oil disrupts the burn and thus the energy released).


Improves MPG as the engine will run at optimum timing advance instead of KR pulling timing. Average MPG improvement with E2-X series is 1-3.


Other than that, the port injection engines are not subject to the intake valve coking issues all GDI engines are (as of 2016 ALL GM gas engines are now GDI) as the fuel would cool and keep them deposit free. GDI has not fuel touching the valves and anyone just has to pull their IM at 10k miles to see how severe this is. This also causes premature wear to the valve guides as these hard deposits are drawn up into the guides with each cycle. Also, as the deposits grow, of a larger chunk breaks loose, it can become trapped between the valve and seat allowing PTV contact and bent valves:


"]http://s1083.photobucket.com/user/tech17/media/valve%20bent%20by%20coking_zpslokaym2f.jpg.html][/URL]


And although BMW has a history of the worst severity, GM is a close second:





And although solvent based upper induction cleaners like Seafoam and BG can be safely used on port injection engines due to the "soft" carbon it loosens, on GDI engines great care must be used as the hard crystalline abrasive deposits ("hard carbon") when broken loose causes scouring (scratches) to pistons and cylinder walls and other damage. So, if you have a GDI engine w/more than say 10-15k miles,a MANUAL cleaning is the only safe way to clean the valves. The Elite E2 and E2-X systems prevent 95% plus of these deposits from forming as well.

I appreciate this write up and would agree with everything you have said.