Oil cap and Performance...

Sparky828 · Post by **Sparky828** » Mon Nov 07, 2005 9:45 pm

Hey I was wondering if having no oil cap would affect performance at all? Why or Why not? Thanx

Anonymous User · Post by **Anonymous User** » Mon Nov 07, 2005 9:49 pm

why would u even want to drive around without an oil cap????

J-Villa · Post by **J-Villa** » Mon Nov 07, 2005 9:51 pm

as embarrassed as i am to say this when i changed my oil one time i forgot to put the cap on....i rechecked the oil the next day...sure enough the cap was still in my engine bay....actually didn't notice any difference...

Sparky828 · Post by **Sparky828** » Mon Nov 07, 2005 9:58 pm

mine felt rough without it... and didnt seem to rev as fast?

rice_eater · Post by **rice_eater** » Tue Nov 08, 2005 1:58 am

well it may not lubricate as well or you could increase the pressure in your crank case from all the air you're sucking in... i think it was that increase in pressure that was making it feel rough and nonresponsive but i cant tell you for sure

refect · Post by **refect** » Tue Nov 08, 2005 5:38 pm

mine was loose and wasnt really screwed on at all. my car didnt really feel any different either. it seems pretty logical though to wat rice_eater was saying. i could see that happening due to no oil cap. i also had oil all on my valve cover when mine wasnt on all the way...

edit:
i guess only way to really test if it changes pressure would be to get a oil pressure gauge installed and drive for a little with the cap off and see if it is any different...

BlackRoseRacing · Post by **BlackRoseRacing** » Tue Nov 08, 2005 6:34 pm

Having no cap on does not create more pressure in the crankcase...
There is a sweet spot for the crankcase to have exactly a negative pressure. You DONT want positve, and OE they try to keep Atmospheric pressure in there.
To much vaccuum causes premature ring where, to much pressure causes blowby,oil leaks..etc....
You basically want to keep it a neutral setting, no vaccuum or pressure. a lil vacuum helps performance wise but not much. With the cap off, all your going todo is create a mess. No gains, No loses...

Sparky828 · Post by **Sparky828** » Tue Nov 08, 2005 8:29 pm

thanks for the anwsers guys i appreciate it... I did not lose any oil though and i went down the track twice. Would it matter in retrospect to 1/4 mile times though?

rice_eater · Post by **rice_eater** » Wed Nov 09, 2005 2:13 am

BlackRoseRacing wrote:
Having no cap on does not create more pressure in the crankcase...
There is a sweet spot for the crankcase to have exactly a negative pressure. You DONT want positve, and OE they try to keep Atmospheric pressure in there.
To much vaccuum causes premature ring where, to much pressure causes blowby,oil leaks..etc....
You basically want to keep it a neutral setting, no vaccuum or pressure. a lil vacuum helps performance wise but not much. With the cap off, all your going todo is create a mess. No gains, No loses...

sweet...i thought it was a bit far fetched myself, but since he lost power i cant think of another reason why no cap would cause that