I switched from mobil 1 5dub30 to 10dub30..

For some reason, after about 700 miles my engine feels quite a bit weaker. Like say 3-6 whp weaker is my guess. Can this really be what's causing this?

I don't burn oil and my compression is good. I also have my valves adjusted. Maybe I need a new fuel filter.. but I think it's the oil.

 

i doubt it's the oil...you're probably just really used to your car's power and that's why it feels sluggish

 

I'm betting this is right... changing your oil to 10w30 won't cause any change in power that you will notice.

 

I've read somewhere that someone did a dyno right after switching to a higher weight oil.. and they lost like 6 whp. And since honda says to use 5w30... it makes me wonder..

 

I suppose it's possible. :shrugs: I don't know enough to say with certainty either way.

 

I wouldn't doubt a minimal power loss, but 3-6hp seems a lot.. Hell, I don't know..

 

It's in your head. If you don't consume any oil, I would stick with M1 5w30.

 

5W-30 and 10W-30 will behave nearly, if not totally, identical when at your engine is at operating temperature.

At colder temps the 5W-30 will behave a like a 5 weight oil and the 10W-30 will behave like a 10 weight oil (obviously).

Although the 5W-30 oil has more viscosity improvers than the 10W-30 this will not lead to increased efficiency of your engine.

It is all in your head.

-kenji

 

Exactally. The only thing I can think, is if you had someone else do the oil change, and they put too much oil in it. That will cost you performance.