Does anyone know the average HP loss going from a light oil to a heavy oil? Lets take a small 4 cyl engine; how much "loss" of HP is there between running a 5w-20 v/s a 5w-50 oil? Is there a large difference based on engine speed/load? Hapuna
quote:Which brands? You really shouldn't have noticed much difference at all, since your viscosity probably only changed from 8.5cst at 100c up to 10.5cst. That 2cst difference wouldn't show up as more than a single horsepower, maybe two. Even if you went from an 8cst oil to a 12cst oil, it probably wouldn't lose you enough power to notice. Going from 8cst to 17cst though, THAT would be noticeable. The average person usually can't discern between a 5hp increase or decrease on their cars in the SOTP meter. [ July 17, 2003, 09:31 AM: Message edited by: Patman ]
Originally posted by Schmoe: I've noticed a difference going from a 5W-20 to a 5W-30 in my 02 V6 Accord.
quote:Actually, with a thicker oil, it absorbs the sound more, so your engine will often be quieter and run smoother, making some people automatically assume that this is the best thing for long engine life. Slick 50 has that same effect too though, and we all know the horror stories with those products.
It is interesting that an engine may seem to run better with a certain viscosity . I don,t know what it may mean ,I have noticed it. Is it the sealing or the cushioning of the oil film?
quote:looks to me like <5% over a serious amount of grade drop...
Originally posted by sbc350gearhead: This may be like comparing apples to oranges but.......Car Craft did a test last year comparing oils on a performance ford engine (390 IIRC)with well over 400HP. They started with a conventional 20w50 as a baseline. They gained 10HP by changing to a conventional 10w30. They gained another 10HP by switching from the 10w30 to mobil 1 0w30. Like I said, comparing synthetics to conventionals in not exactly scientific (especially in a built to the hilt motor).