I wonder if the 10W-30 has seal conditioners similar to other "high-mileage" formulations. If it does, then would it be unecessary/harmful to the engine to have our seals swell when they're still in good shape?

 

[QUOTE]Originally posted by BillK
[B]Now is the base composition significant?

 

I changed to the Supersyn on the last oil change (@15K) and it seems to burn less. I think I was burning just short of 1 qt for 3K miles on the Tri-syn. I'm at 17K now and keep checking and it doesn't seem to be down more than one X. Can't confirm the added mileage, for me it is about the same; 23-24mpg avg.

Joser
Silver/Red

 

[QUOTE]Originally posted by twohoos
[B]The F20C burns oil in VTEC, no matter how few or how many miles on it.

 

"My mileage has gone from 20.5 mpg to 24.5 mpg. If you do the math over the length of an oil change interval, you will see that the new oil is more than paying for itself in gas savings alone."

Sorry, but there is no way. Gas mileage depends on many things. How you drive it, speed, weather, wind, A/C use, and most of all how accurately you measure it and over how many tankfuls you measure it. But there is just no way a different oil will increase gas mileage 20%!

 

This is the internet.....believe whatever you want. I'm merely passing along my personal observations. If you choose not to believe this, that's OK with me. Oh by the way, I'm not going back to dino oil to see what happens.

 

It seems like 90% burn some oil or other. If oil is being burned, wouldn't that leave a residue inside the engine???

 

When compared to normal mineral based oil, synthetic oils reduce friction, resulting in lower operating temperatures and IMPROVED gas mileage. And when making that comparison, the assumption is that all the variables remain the same except for a change in the type of oil. So an improvement of 3 to 4 mpg is not out of line.

 

By "inside the engine" did you mean the crankcase? In order for the oil to be burned, that means it has to get into the combustion chamber somehow. The easiest way for that to happen with a new engine is for the oil to be left on the cylinder walls. For the oil to be left on the cylinder walls, the rings can't be doing their job very well (not broken in yet?). The piston rings are there to keep the combustion gasses in the combustion chamber and also to control the oil (keep it out of the combustion chamber). Other things like worn main bearings which will throw too much oil on the cylinder walls or too much oil in the sump which will cause too much oil to be splashed on the cylinder walls can cause oil consumption, also.

Engines are designed to use a little oil as they are run. That would be normal. If the rings are really worn, you could have a condition known as "blow by" and this means that combustion gasses are being "blown by" the rings and are entering the crankcase. If the rings are that worn, then you would most likely be burning a fairly large amount of oil, I would think. In this case, I would think that you could expect a residue in the crankcase.

Does this help?
Bob

 

It could also leave a residue in the exhaust ports. I noticed thick black grime in the exhaust ports of my S2000 when I took the exhaust manifold off; at the time I was burning oil.