Synthetic is bad?

[tracy]

Was just reading the Cams and Synthetic thread. I thought synthetic was good for our motors? Can someone clarify.

 

[V6 Beast]

According to a guy at Reed Cams, the Synthetic can be so slick it prevents the lifters from getting the proper "spinning" motion in the bores that they are supposed to have.

Synthetic is good because it tolerates heat better and doesn't "cook" onto the turbo bearings. I have good success with good old Dino oil and letting the car idle for 30-60 secs if I have been driving it really hard.

Sully

 

[Slow91z]

I "think" the whole synthetic being bad is just for the cam break-in, but if you go with a roller cam you don't have to worry about it.

 

[bruce]

At elevate oil temps., syns can show an advantage. Have you noticed in the commercials they show 450dF?.
Ya think that's just by chance?.
Has anyone here seen an oil temp over 300dF?.
OK, I'll go 350.

Bueller?.
Bueller?.

OK, now that we're back to reality, you'll also note how everyone now has syns.. Guess what, they changed what how much petro oil the syns can legally have in them. Ahh, merchandizing.

And in the Enzo Ferrari they use some special blend of Shell oil that $70 a quart, so if you really want the best protection, might try running that.

It's that lack of contaminents that keeps an oil *good*. Change it resonably often, and you'll be fine.

And with the money you save, do the routine stuff folks ignore like brake fluid flushes, tranny fluid/coolant changes, etc..

 

[turbo nasty]

I don't care what kinda lube u have once it gets alot of crap in suspension...it is done.

 

[turbowidow]

from my experience in the air compressor field and the dealings w/ numerous oil manufactures i have seen oil break down in temps as low as 190*F (extended periods at this temp). the main thing we preach are routine air and oil filter service AND oil analisys. the rotory screw compressors of today are using synthetics that can go 10k hours and beyond before change out and most manufactures now offer 5yr warranties on the airends( and in this business they never"give" anything away- they found that the synthetics offered that much more to the longevity of the airends). i now run synthetic in anything i own.

 

[GNVYUS 1]

I could of sworn when synths first came out they were bragging about how fast it can work through the motor on start up. This is the main reason I started using it, to help dry starts. Breaking in motors used to be a no no with synths until the Vettes started using it 100% of the time from the factory.

But with the preluber, its back to dino oil and 2,000 mile changes. Contaminents will hurt both oils equally, so I change it every 2,000 miles and its not much of an issue. Synths can go 3 to 5k which was were your money savings started to come into play, but I do not want oil in my motor/turbo that long.

 

[turbov6joe]

Last year was the first time I ever used a fully synthetic oil. To keep it clean I got into the habit of changing the filter every so many times to the track and adding 1 quart to replace what was lost in the the filter. When I pulled the motor apart a few weeks ago everything looked real good...can't say for sure if it was the oil or not. In years past I always used Castrol 10w-40 and a new filter every month or so depending how many passes the motor had on it. When I pulled those motors apart they also looked real good inside. So, I'm not fully convinced that the synthetic oil did anything special for the motor. Hell, this go around with the synthetic was the first time I wiped out a cam lobe???

 

[JoeNational]

See i never wanted to use syn. but then was told to use a mix of standard and syn. so now i use 3 quarts reg. and 2 quarts syn and have no problems.

 

[Razor]

Originally posted by turbov6joe
So, I'm not fully convinced that the synthetic oil did anything special for the motor. Hell, this go around with the synthetic was the first time I wiped out a cam lobe???

humm guess why I put the cams+synthetic thread up. I remembered you wiped your cam..coincidence

My buddy with a GN has a 210/205 uses dino oil and been there over 20 k miles, 8 HG's, 2 rebuilds, etc.. cam is still ok.

Just my .02.

On a roller cam.. no brainer.. but when a cam mfg says no.. especially on our wonderfully designed lifter bore/cam alignment block.. then its a time to reconsider :/

2k miles.. man that must be some soft driving.. i've changed oil at 250 miles

 

[Race Jace]

I use synthetic in my car, why? For that amount of money it just makes me feel better that i have better oil in it. Is it really superior to regular non syn? I don't really know. I just have to go by what the oil manufactures tell me.

here is some interesting reading about oil,change intervals and brand. This guy is pretty smart and is doing the best he can to have a controlled study. It leads you to believe that changing the oil regularly is not as necessary as we all thought.

http://neptune.spacebears.com/cars/stories/oil-life.html

 

[strikeeagle]

Anyone who thinks synthetics aren't vastly superior to non-synthetics needs to wake up, climb off Arnie's tractor, and join us in the 21st century...

IMO, the advantages of synthetics have nothing to do with extended oil change interval - regular oil changes are needed regardless if for no other reason than the huge injectors we run blow a lot of raw fuel into the pan...

The advantages of synthetics are they are plumbable in the cold, viscous in the heat, less prone to coking and don't pound out of the bearings when you detonate your motor (like you've never detonated your motor)...

 

[Razor]

What bout the grinding cam issue

I didnt say synthetic oil isnt superior..but the point is if its too slippery.. cam may get whacked. Talking flat tappet cam..aka non-roller

If I pull the dipstick and the oil is honey colored.. I dont do squat..I pull the dipstick and its dark.. it gets changed.

can it be easier?

 

[n20junkie]

this is just me thinking, but if the flat tappet lifters wern't turning with synthetic oil due to the fact that the oil was too slipery, then how was it wearing the cams out, if it can't get enough contact to turn a lubed lifter, where did the wear come from to whipe a lobe, i think it is a bunch of BS personaly, and as an aircraft mechanic working for the military, we use synthetic in turbine engines for as long as it doesn't get contaminated by metal, we NEVER do an oil change, no such thing unless something lets go, the only real reason to change the oil in anything is for 3 reasons, contamination from some source, oil molecule breakdown caused by oil shear in the pumping section, or lastley by oil breakdown by heat, and in the breakdown catigory synth is superior in every way compared to mineral based oils which is why the oil change intervil is extendd in cars with its use, and oil contamination in stock cars is minimal due to percision fuel control and tune, but in older cars or those that have been modified, the interval of oil changes is based on the rate of contamination which is uneffected by oil type if the sole source of contamination is combustion byproducts, personally i run my cars rich to stay safe but i change the oil after any racing event or 2,000 miles. i think that if synth oil was causing a problem it would of been picked up by now with all the flat tappet cams in the world, but that just me.
Grant

 

[buickpower]

even if the cam can't get enough static friction to turn a lubed lifter, the load, which is rather high (like 200, 000 psi +) is still there. its like rolling a metal ball or disk on an oiled metal surface with no slippage, while applying a downward force on it, versus holding it and pushing down with your hand so that it cant rotate, and sliding it on that same surface. naturally the second scenario will yield higher wear. The main difference here is that the first case had minimal or no slippage (i.e. abrasive metal contact), whereas the second case did.

 

[n20junkie]

i understand the scenerio that was explained, but here's why i don't think that its a good analogy, first off the static load is there, but it is being supported by the fluid layer of oil, which acts like micro ball bearings that is how lubricants are typed, by the size of the molecules and there ability to remain intact under load, so if the fluid is supporting the load to the point where there is not rotation, and if you think of the force required to rotate a lifter its soo insignificant compared to the pressures exerted on the face of the lifter, and if this rotation force is not enough to turn the lifter than the actual wear can be almost zero because if there was wear then the lifter would turn, and the bearing analogy was flawed in one respect, you said that when HELD by your hand increased wear would occur, which is true becasue the lack of rotation would prevent the intake of oil between the 2 bearing surfaces, but no one is holding these lifters, they are free to rotate, and if there was enough force to cause the wear described in the bearing story then the lifter would just turn, it wouldn't just sit there.
Grant

 

[buickpower]

I definitely see what you are saying, but i think that when the cam is on it's base circle, and valvespring pressure is its lowest, the fluid friction on the inside of the lifter bore (which is actually rather high because the tolerance is pretty close), combined with the lower vertical load of spring seat pressure applied to the lifter via the pushrod, may be substantial enough to be larger than the static friction due to the fluid molecules you mentioned on the face of the cam lobe, and the oil molecules may be slick enough to slip. Like I said , i think that this really only happens on the base circle when the spring pressure is lowest. This is only my opinion though.

 

[V6 Beast]

I thought it wore off the lobe because it built up excessive heat. With the lifter spinning, it was able to disipate the heat better because different parts of the lifter face made contact with cam.. I have no idea.. Why don't ask the cam manufacturer who started this rumor? who was it again?

Sully

 

[Razor]

Well all of this that makes sense it normal terms doesnt apply to exhuast lobes on our cams. Especially cyl 1&3..

Why else would ruggles back cut those lobes in an effort to correct an "issue"

So in a perfect world things being what they are, great. I only brought the issue up becuase it seems there are a lot of guys that have experienced the flat tappet wiped cam syndrome on theyre Buick motors..

Sully.. you know that I know, that U know who said what to whom

Hog wash or has teeth

Cheers.. the plot thickens

 

[Red Regal T]

With 250,000 miles on my stock cam, and using the ever dangerous HV oil pump for 155,000 miles, with conventional oil no less, I'm wondering if I'll ever make it to 300,000 miles. Lookin' for some experts to set me straight.