Originally Posted By: ChrisD46
OK , I found a scientific study on GDI engine deposits (it gets pretty interesting 2/3rds thru the study )
http://www.pecj.or.jp/japanese/overseas/conference/pdf/conference12-19.pdf
What I take away from this study :
1) Use Top Tier gas
2) Don't "lug" a GDI engine
3) Use a top quality , low NOACK oil
4) Change the oil early and often.
5) Aftermarket gas additives probably do little in a GDI engine
** What I can't determine is if the study shows a benefit to using a synthetic Group IV oil and changing it early / often has an advantage over doing the same with Group III or Group II oils ?
Interesting study and thanks for posting...
From reviewing page 16/20, it looks as if fresh oil makes the biggest difference where oil is concerned, more so than does GrpII vs GrpIII (a very small difference is seen between these in the graphs). GrpIV being the exception as it shows a more distinct advantage. All in all, your other takes fall in line with mine.