I just did a fresh oil change and went to Mobil 1 synthetic 15w50. The car has 200,000km or about 120,000miles and it always smoked a bit on start up even after I did the valve seals. I was not too sure about putting the synthetic in the motor because I have hear of motors comingapart with it. My friend took out 2 crower cams in his 427 with it. ANYWAY I had heard it might smoke a bit more and it did ....A LOT MORE. I started it the next 2 days and it was a friggin smake screen in the driveway. Now the odd thing is I have been starting it ever since and I don't see any smoke at all on cold starts now. I am quite impressed. I don't know what i did but I like it!

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91 Z28 Camaro
305 TPI
Flowmaster 3" exhaust
700R4 with 2000 Stall and shift kit 3.42 rearend
Autometer shiftlight tach and B&M mega shifter
One sweet sounding system

 

Ever since I changed to syn my car doesnt smoke on start up eather.

 

I ran a half mix of M1 in the grand prix i was sporting last year and it made the same difference in oil smoke. My theory is the synthetic cleans teh cylinder walls/rings and helps them seal better.
Also worth noting that the LB9 in my 92 has almost 90k miles on it and it doesn't have any valve seal problems whatsoever. It's been a synthetic baby it's whole life (bought from original owner.), so perhaps it does help keep the seals fresher than dino juice.
...ed

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Ed Maher - Moderator @ The Carb Board
92 Z28 Convertible - Quasar blue / Tan top
LB9 4L60 GU2 G80 - stock, soon to be sleeper
-=ICON Motorsports=-

- Definitely prototypes, high powered mutants of some kind. Too weird to live, too cool to die

 

I am ticked pink but it cost alot of money to do an oil change. I dropped $42 on oil and a filter OUCH! I don't think i am going to do the ritual 4000KM now. How long do you guys leave it in for?

 

42 on oil? Mobil 1 costs me 4.25 and filter 3 so thats around 25 bucks. I change my oil once a year. I only drive the car 4500 to 5000 miles a year.

 

Hey guys,
Wanted to pass this along...adding synthetic to an tired engine that smokes at times is also a trick used car sales do...I knew a guy who dealed with going to auctions for cars and alot of high mileage cars they were going to sell there smoked a bit of oil..they would have the synthetic oil change and it would appear to go away.
Impressive stuff eh?

He says it just burns the oil cleaner...not as noticeable as dino oil.

Do keep an eye on your oil level over time because you may still be burning some but wont notice it out the tail pipes.Either way, synthetic oil in a good runnng engine can go over 7,000 miles or more before needding to be changed.

 

$25 I wish!! I live in Canada the land of double the price ans 15% taxes. It cost alot to do anything to your car here. If you want something on your car double the american price. Imagine anything you do costs you twice as much and see how many mods u can get.

 

I go 10,000 miles or a year whichever comes first. It use to say 25,000 miles on the cans but they took it off. As far as your friend losing 2 cams because of synthetic oil that is BS!

 

lol, can't say i'd be brave enough to let my car go 10,000 miles....then again i've always gone by the rule of thumb "Every 3,000 miles"...

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89 IROC-Z 350 TPI

-Flowmaster Catback
-Performance Resource Chip
-700R4 (Rebuilt) Too much done to actually list
-K&N Airfilters
-Ported Plenum
-2.77 Gears (not much to brag about but eh, its there)
-MSD 8.5 mm plug wires
-Gutted cat
-!AIR
-Gutted Air Boxes

 

15W50? Holy crap! Do you live near the equator or something? That's damned near as thick as gear oil!

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The IROC Homepage
<A HREF="http://www.rit.edu/~jli4307/camaro" TARGET=_blank>
View the restoration of an 85 IROC</A>
"I didn't know a bored out Ford could go so slow" -Shenandoah

 

What weight oil were you using before?

If it was 10W30 or 5W30 then your engine probably would not be smoking anymore when you put in 15W50. Usually one only uses oil that thick on an engine w/ bad rings/seals to stop the leaking.

Dale

 

Odd that you should mention the gear oil thing. More on that later...

I'm using 15W50 Mobil 1 in everything during the summer months. What is important to remember is that the multigrade oils are rated at the viscosity of the base stock, and the other number is a contrived number that supposedly represents how the oil ACTS (not truly IS) at higher temperatures.

What is even more strange about the antiquated SAE oil viscosity rating system is that is applies even less to synthetics, since synthetics are generally more thermally stable, and tend to remain a a constant viscosity to a much higher temperature than mineral oils with viscosity improver packages.

If you really want to know what is in your crankcase, use the ISO or SUS viscosity numbers. They are a true representation of the viscosity of the oil. For example, the 90-year-old SAE viscosity indexing rates an engine oil with an ISO 32 viscosity (SUS 150) at "10W". The SAME viscosity oil used in a gearbox or differential is SAE rated at "75W", but it's the SAME FRIGGIN' VISCOSITY!

Even more confusing, a straight SAE 10 oil is actually a higher viscosity than "10W" oil - ISO 46 versus ISO 32! The viscosity cup and stopwatch doesn't lie, but SAE isn't telling the whole story.

If you learn a little more about what you're dumping in your "prized" equipment, you'll probably never use mineral oil again, and will certainly want to know more about the oil than the API or SAE information provides.

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Later,
Vader
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"Let the bodies hit the floor!"
Adobe Acrobat Reader

 

In case you were curious...



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Later,
Vader
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"Let the bodies hit the floor!"
Adobe Acrobat Reader

 

So what exactly is the difference bewtween gear oil and motor oil then? ~Arnold

 

Well it is like this. I was running castrol 10w30 and the car worked just fine. It get pretty hot here and my motor is tired so I put in the 15w50. I like running heavy oil especially with synthetic because it runs like water compared to reg oil. Synthetic does lubricate better but if it all runs out my tail pipe it is no good to me.'

And yes I have driven the car the cam came out of. It was a 1968 Caprice numbers matching 427CI/th400. It had a crower cam and it work very respectable. We changed the oil to Irving synthetic and it chewed a couple lobes off the cam. We changed the cam and it did it again. Finally we went back to the old oil and put a smogger 427 cam in it and it works great. The car is long since gone and the motor is in his 66 biscayne just to move it. Now it has a monster cam in it. It will barely idle but it is just one of those magic motors that keeps on going for some reason.

 

Arnold,

Gear oil has extreme pressure and antiwear additives to enhance the base stock. Ususally the extreme pressure component is primariyl sulfur, and the antiwear components are primarily zinc. The sulfur additives are what give gear oil that familiar, "pleasing" aroma.

If you don't belive me, get a viscosity cup and stopwatch, then start wasting some oil. You can use the same equipment and a domestic refrigerator/freezer to test the thermal stabiliy of mineral versus synthetic engine oils, too. If you do some research and homework, you'll probably scare yourself into being an avowed synthetic user. I did years ago with industrial equipment, adn applied the same philosophy to my cars, even though replaceing a car engine is a lot cheaper than a $2 million machine.

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Later,
Vader
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"Let the bodies hit the floor!"
Adobe Acrobat Reader

 

So to get bacl to the original post, about this 427... what valve springs were in it? You know of course that the stock (or stock replacement) ones are basically the worst part ever made for anything resembling a high-perf engine. That's why he rolled off 2 big racing cams so bad, it had nothing to do with the oil, or Crower's qulaity control for that matter. Those stock springs won't even work with something as mild as a regular Comp 280.

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"So many Mustangs, so little time..."
ICON Motorsports

 

Trust me there was enough valve sping to handle the cam. The same springs are in it and he is now supposed to me running a ZL1 cam or something. I have just puttered with it and the thing lopes like crazy. Sounds sweet. I think it was just the type of synthetic. I am not saying crower cams suck....I am not saying synthetic sucks. What I am saying is it has its place like everything else. I would love to see you break a motor in with synthetic. It just sticks to the bearings too good. Synthetic didn't like an old motor that had run leaded gas and towed more things than a tug boat. The motor is still running strong. It is one of those magic ones that you can pound and pound and it works amazing and stays together. Infact it works much better then the new 427 in his 72 chev 1/2 ton.