The LS comes with Ecotec...the base gets the 115hp pushrod.
Probably because at that rate of rotation they're hitting droplets that would normally just drop to the pan. They're creating their own windmill that creates other issues then your typical engine ..or it could be just one more thing to squeeze .09 hp out of it.quote:
Originally posted by CBDFrontier06:
Why do I see engine shops grinding crank counterweights to a sharp edge on the forward rotating side?
I want to know why you would ever consider grinding a counterweight. You would throw the primary balance off and make the engine vibrate terribly, not to mention all the additional wear on the bearings.quote:
Originally posted by Gary Allan:
Probably because at that rate of rotation they're hitting droplets that would normally just drop to the pan. They're creating their own windmill that creates other issues then your typical engine ..or it could be just one more thing to squeeze .09 hp out of it.quote:
Originally posted by CBDFrontier06:
Why do I see engine shops grinding crank counterweights to a sharp edge on the forward rotating side?
I believe that true "splash" lubrication (not the end of the rods for the piston/cylinder walls) was abandoned about 40 years ago (maybe longer).
It's called knife edging. Good for a few HP above 5 or 6000 rpm. This is for all out engines and naturally, the crank is rebalanced.quote:
Originally posted by GMorg:
Matt_S wrote: "I want to know why you would ever consider grinding a counterweight."
The grinding I have seen is on cranks that were cast with some "finishing" in mind, and it is done prior to final balancing.
This is not a mythical event. I imagine it would depend on the design and age of the engine, but 20w-50 had a substantial effect on my Mitsu 3.0 when compared to 5w-20. It was "tighter" feeling.quote:
2. In persuit of the "smoother tighter feeling." Sounds silly I know.
In my opinion, it would depend on the number of cold starts/mile. The more starts/mile ..the more it will impact fuel economy. If you're a 50 mile/day commuter ..probably ZERO. If you're a 5 mile/day commuter ...probably substantial. That's my experience with engines that have a variance in economy due to visocity ..some do not (my jeep engines consume excess fuel just running anyway).quote:
Would a thicker oil reduce MPG in any way? Would it alter MPG in a material way?
I did just that that night. Drained out the Chevron Supreme 10W-30 and poured in 10W-40 MaxLife. So far the engine has NOT blown up yet. I only drove it about a mile after the oil change. The first thing I noticed was an increase in oil pressure at 185F idle speed from 45psi with 10W-30 to 60psi with the 10W-40.quote:
I seriously think this engine likes a heavier oil... Am tempted to try a 40 weight this summer.
I just put 10w40 maxlife in my 98 mazda 626 2.0. The only differance I have noticed so far is no oil consumption but more time will tell. My car does spec for 10w30 however the same engine in Austrailia specs 10w40 and 15w40.quote:
Originally posted by GoldenRod:
I did just that that night. Drained out the Chevron Supreme 10W-30 and poured in 10W-40 MaxLife. So far the engine has NOT blown up yet. I only drove it about a mile after the oil change. The first thing I noticed was an increase in oil pressure at 185F idle speed from 45psi with 10W-30 to 60psi with the 10W-40.quote:
I seriously think this engine likes a heavier oil... Am tempted to try a 40 weight this summer.
The engine spins faster at startup then it did with 10W-30. That of course does not make sense, because lighter oils usually give you faster startups. The oil is a thin 10W-40 being 13.9 cSt @ 100C. In comparison, Havoline 10W-40 is 15.9 cSt @ 100C. I'll keep you guys posted on how it does.
GR
It's 3800V6 in a little Buick. I'm not worried about the increase in oil pressure, although I am surprised by the amount of increase.quote:
GoldenRod - I read the thread again and didn't see your car/engine. Probably missed it badly Am I guessing you have the ecotec too?
Once the oil pressure is above specs, you're really not gaining anything. And if you reach the oil pump bypass pressure at a lower RPM than spec, you lowered the oil flow through the engine at RPMs above this point. Increased viscous heating in the bearings coupled with reduced flow isn't helping the bearings or the rollerized valvetrain any. Piston ring and valve guide seal are the only areas that might benefit if you don't see an proportional increase in oil temps. Will your engine blow up? No. Will it wear out sooner? Probably not. But you probably lost a little fuel efficency.quote:
Originally posted by GoldenRod:
The first thing I noticed was an increase in oil pressure at 185F idle speed from 45psi with 10W-30 to 60psi with the 10W-40.
3800s have piston slap issues?quote:
Originally posted by cousincletus:
I have a 2002 Cavalier and have a little piston slap on startup in the winter.
Yes, I'm with 427 here. Once you're up against the relief you have no idea of what the flow rate is. You may assume that, given the higher pressure, that any flow would be higher. In reality what you have is a variable flow based on visc 24/7. The colder ..less flow ..hotter more flow ..but you just don't know how much since you've changed the flow dynamics of the circuit from series to parallel.quote:
Originally posted by 427Z06:
Once the oil pressure is above specs, you're really not gaining anything. And if you reach the oil pump bypass pressure at a lower RPM than spec, you lowered the oil flow through the engine at RPMs above this point. Increased viscous heating in the bearings coupled with reduced flow isn't helping the bearings or the rollerized valvetrain any. Piston ring and valve guide seal are the only areas that might benefit if you don't see an proportional increase in oil temps. Will your engine blow up? No. Will it wear out sooner? Probably not. But you probably lost a little fuel efficency.quote:
Originally posted by GoldenRod:
The first thing I noticed was an increase in oil pressure at 185F idle speed from 45psi with 10W-30 to 60psi with the 10W-40.