here ya go. http://www.svtperformance.com/forums/showthread.php?s=&threadid=28465

Cobra'03 is the authority on oils on that site.

 

Ive been using RP for years. Its funny because each year someone tries to disprove that their oil is a false breed of synthetic. They tout that there Mobil 1 or Amsoil is best. RP doesnt have to disclose anything to some goon who wants to research what their oil is made of. Sure, lets just hand over our recipe to someone and let it get into the hands of another oil company. Why do you think Mobil redeisgned their oil with superSyn? They are trying to catch up to RP.

Ill tell you how good RP is. I was able to continue to drive on a #7 Spun Rod Bearing with a nice knock for 10,000 miles.

 

Royal Purple kicks butt. Thats all I've run for the last 30k or so. Mobil 1 is garbage IMO. I used it twice, and both times, drained out looking like tar. I change my RP at about 7-8k miles. Drains out still looking pretty damn good....and I've used the same filter with both types of oil so it's not that. I've been like 2 quarts low for a couple months, not knowing it, and winding my car up to redline a few times a day. Engine doesnt seem to mind at all. I beat the hell out of it and my compression is still good.

 

Well, I'm a firm believer in RP! No slam against Mobil 1 as I have used it since it came out in the 70s. I still use it in my wife's '97 Gran Prix and in my '97, 4.6l XLT F150.

I put RP in my 01 L at 4,000 miles along with a K&N Gold oil filter. I've changed every 6-8k since then. I now have 42,600 miles on my L as it's a daily driver/quarter-mile racer. I have about 7 extra lbs of boost and my best et is a 12.532@108.31. I just dynoed(for the third time) it yesterday at South Georgia Corvettes in Thomasville, Ga. I don't have the graphs in front of me but it's best pull was a 400.2/502.1, SAE corrected.

I attribute its longevity, power, and quietness(no start-up 'noises'--ever) to the RP.

Dan

 

...

Ill tell you how good RP is. I was able to continue to drive on a #7 Spun Rod Bearing with a nice knock for 10,000 miles.

Uh, did you spin the #7 bearing while using RP?

 

Where is the best and cheapest place to purchase royal purple products?

 

Venom25

I just did a search on Royal Purple and the first listing was Northern Auto Parts.com...ordered on line $4.99 a quart plus shiping. 12 quarts to a case (ordered a case).

 

Uh, did you spin the #7 bearing while using RP?

Spun it using mobil 1

 

Boy, all this overwhelming anecdotal evidence makes me want to rush right out!

Pullease. You guys sound like the sucker that puts in duralube!

Re: the spun bearing - it is unlikely that you ran it that long spun. Loose, perhaps. Crank journal shot, yup. Spun? No. No oil in the world can make up for a 1/8" gap between the rod and crank. Not to mention all the metal in the oil system and the profound lack of oil pressure a spun bearing causes.

Oil won't cause a spun bearing. Only a lack of it, or a bent rod or some other mechanical malady beyond any oil's ability to fix.

Besides, I could care less how an oil performs while driving aroung with a spun bearing.

If you have a preference for an oil, that's ok. If you would like to present some hard wear data or a chemical/metallurgical analysis, that would be great.

Bottom line: standard dyno juice will work fine 99.9% of the time if changed often and the right grade is used. For that extra margin, you can't beat synthetics. Is there a diff between these various brands of synthetics? Probably. Would it really matter? Probably not.

Every brand will pull out some specific test that they know beforehand their oil will do better on than brand x. Most of these demos have no bearing (sorry!) on operation in the real world. Pick what you feel best with, then go spank a Cambird or two.

- Dave (SCOA #1474)
'01 Cobra Coupe (Laser Red, Charcoal), no wing
- #812 of 3867, born 5/7/01
- Dyno results (7/10/01, bone stock): 273rwhp, 277ft-lbs
- Best ET: 13.724 @ 103.16, 60'=2.239 (10/23/02)
- Firestone SZ50EP, 275/40/17, on CobraR wheels
- TriAx shifter w/stock handle
- Bassani CatBack system (8/1/01)
- Griggs sub frame connectors (8/18/01)
- MM strut tower and K brace (10/13/01)
- 100MM Densecharger (10/27/01)
- '03 Cobra coupe Bilsteins, MM CC plates (8/11/02)
- 3.73 Richmond gears (12/22/02)
- '03 Cobra pinion brace, Steeda bushings (12/22/02)

 

Boy, all this overwhelming anecdotal evidence makes me want to rush right out!

Pullease. You guys sound like the sucker that puts in duralube!

Re: the spun bearing - it is unlikely that you ran it that long spun. Loose, perhaps. Crank journal shot, yup. Spun? No. No oil in the world can make up for a 1/8" gap between the rod and crank. Not to mention all the metal in the oil system and the profound lack of oil pressure a spun bearing causes.

Oil won't cause a spun bearing. Only a lack of it, or a bent rod or some other mechanical malady beyond any oil's ability to fix.

Besides, I could care less how an oil performs while driving aroung with a spun bearing.

If you have a preference for an oil, that's ok. If you would like to present some hard wear data or a chemical/metallurgical analysis, that would be great.

Bottom line: standard dyno juice will work fine 99.9% of the time if changed often and the right grade is used. For that extra margin, you can't beat synthetics. Is there a diff between these various brands of synthetics? Probably. Would it really matter? Probably not.

Every brand will pull out some specific test that they know beforehand their oil will do better on than brand x. Most of these demos have no bearing (sorry!) on operation in the real world. Pick what you feel best with, then go spank a Cambird or two.

Totally agree...

Mobil 1 is garbage IMO. I used it twice, and both times, drained out looking like tar.

I use Mobil 1...have been since the car had 1,000 miles on it, and the car does not use oil. I sometimes have to add maybe a quarter (probably less) of the bottle close to the 3,000 mark, but thats with *A LOT* of high rpm driving... The oil is far from looking like tar (actually not much darker than when I put it in) when being drained (3,500 miles) with both city/highway/racing... Mobil 1 has been around for over 25 years, with a strong history in racing, and OEM platforms (Porsche, Viper, Mercedes (AMG), Corvette, etc...) IMHO, its one of the best synthetic oils out there along with Redline, Amsoil, RP... Not knocking RP (I know its good stuff), but I just don't get into the BS that it's the God of all oils and that it puts the others to shame...

The purple dye in RP is a gimmick BTW...its adds nothing but a cost in the price...

 

Re: the spun bearing - it is unlikely that you ran it that long spun. Loose, perhaps. Crank journal shot, yup. Spun? No. No oil in the world can make up for a 1/8" gap between the rod and crank. Not to mention all the metal in the oil system and the profound lack of oil pressure a spun bearing causes.

Dude, what are you talking about? He said a SPUN bearing, not a MISSING bearing.
As far as looking like tar, there is no way I could go 8000 miles and drain the Mobil 1 and have it still look fairly fresh. The RP does this. I never believe advertising hype with any product. I've stuck with RP due to my own impressions of the stuff.

 

Dude, what are you talking about? He said a SPUN bearing, not a MISSING bearing.
As far as looking like tar, there is no way I could go 8000 miles and drain the Mobil 1 and have it still look fairly fresh. The RP does this. I never believe advertising hype with any product. I've stuck with RP due to my own impressions of the stuff.

If mobile 1 is coming out looking like tar, it's cause the oil is slick enough to reach places and clean out the carbon and crap from the oil you had before.

And Rp looks like it's dirty when it goes in... how can you tell if it's not worse coming out??

BTW, it's just vegetable dye. That is all I need in my oil... additives that do jack.

 

Dude, what are you talking about? He said a SPUN bearing, not a MISSING bearing.
As far as looking like tar, there is no way I could go 8000 miles and drain the Mobil 1 and have it still look fairly fresh. The RP does this. I never believe advertising hype with any product. I've stuck with RP due to my own impressions of the stuff.

Uh, have you ever seen a spun rod bearing? One half of the shell spins around, partially or completely, to the other shell half. It requires enormous force to squeze that half into the small space, and in the process both bearing halves essentially get shaved.

As a result, the oil system gets filled with metal, and the half (or portion) of the rod's big end that is without a bearing shell pounds against the crank due the large clearance. And of course, oil pressure, esp at idle, will go to near 0 due to the large clearances. Combined with the metal in the oil, this can score cam journels and cause other rod bearings to spin. Beats the hell out of the mains, too. Eventually, the pounding becomes too much for the rod bolts to handle or the twisting rod breaks the piston pin. Usually sticking the rod through the block and the piston into the valves.

No oil in the world can fix this. No way can one drive an engine 10,000 miles this way. I doubt it would last long even at idle.

A rod knock itself does not mean a spun bearing - just that the clearances have opened up. Many causes, but a spun bearing is usually not far behind.

Mobil 1 did NOT cause the failure, nor did RP save the engine.

-Dave

 

Uh, have you ever seen a spun rod bearing? One half of the shell spins around, partially or completely, to the other shell half. It requires enormous force to squeze that half into the small space, and in the process both bearing halves essentially get shaved.

As a result, the oil system gets filled with metal, and the half (or portion) of the rod's big end that is without a bearing shell pounds against the crank due the large clearance. And of course, oil pressure, esp at idle, will go to near 0 due to the large clearances. Combined with the metal in the oil, this can score cam journels and cause other rod bearings to spin. Beats the hell out of the mains, too. Eventually, the pounding becomes too much for the rod bolts to handle or the twisting rod breaks the piston pin. Usually sticking the rod through the block and the piston into the valves.

No oil in the world can fix this. No way can one drive an engine 10,000 miles this way. I doubt it would last long even at idle.

A rod knock itself does not mean a spun bearing - just that the clearances have opened up. Many causes, but a spun bearing is usually not far behind.

Mobil 1 did NOT cause the failure, nor did RP save the engine.

-Dave

Uh, Yes I have seen a spun bearing, smartass. I've machined and built THOUSANDS of engines. I've seen just about anything you could throw at me.
Your definition of a spun bearing is a little wacky. That is one thing i've never seen happen, probably because there's a 1 in a million chance that it will happen...If that.
A spun bearing happens when one bearing surface essentially welds itself to the other bearing surface (the rod journal), and the whole bearing rotates inside the big end of the rod. This of course kills the mounting surface of the bearing and rod, and the only thing holding it in is the "weld". It IS possible to run like this, and maintain oil pressure, because the bearing has sealed off the oil passage in that throw. Now the only thing hopefully being lubricated is the outer shell of the bearing to the mounting surface of the rod. Now it's at the mercy of external oil in the windage area.
One thing you're right about, is that with your extreme idea of what a spun bearing is, RP could not do anything to keep it running for even a minute. No oil could.

 

You're description is of course correct - I've seen that as well. Many wonderful ways to spin a bearing! And perhaps you're description is the prelude to my scenerio - eventually the two halves spinning around will wear to the point where they overlap. The tangs that locate them in the rod can also wear due to a bent rod (causing a rocking motion), allowing the bearing halves to spin as you described.

In either case though, it is generally a lack of oil or severe oil contamination that causes the failure (not to mention a host of other mechanical causes - over-revving, detonation, etc). It was not the Mobil 1, nor was the supposed 10,000 mile survival have anything to do with the RP. If true, it was dumb luck.

Which was my main point - anecdotal stories does not make for good science. But it does sell snake oil products. Does RP fall in that catagory? Eh, probably not.

-Dave

 

I thought the original post was for hard numbers. When I took the Royal Purple fact sheet and compared it with the Mobil1 fact sheet I didn't even see where it was close (Mobil1's numbers were best).

A buddy of mine who is into SCCA racing, driving more closely the types of cars I will drive, sent me a report that rated the oils on a number of characteristics. If my memory serves me correct, Mobil1 came out tops, followed very closely by Castrol, and then the other "Brand" synthetics. Amsoil was in the bottom middle. Royal Purple was a no show.

I was on the RP bend looking for a local distributor to buy from. When I compared the viscosity level of RP and other synthetics, mainly Mobil1, it didn't look as good. That was 15k miles ago and I went with Mobil1. The car has over 22k miles on it now and at a recent oil change at a Ford dealership they said it was the quietest engine they have ever heard, new or old (baring the exhaust note).

 

Interesting reading on rod bearings, etc.:

http://www.bobistheoilguy.com/oilshear.htm

Dan

 

Yup, i just made the whole story up. I had a spun bearing for a whole 125 miles and it locked up


Did you rip down my motor Bower? No you did not, so before you speak, please dont make assumptions unless you saw my motor.

I will continue to use RP as it has served its purpose.

BTW. The oil goes in purple.. When you check the oil level, it shows up clear on the dipstick. Its quite easy to tell when it becomes dirty.

 

Interesting reading on rod bearings, etc.:

http://www.bobistheoilguy.com/oilshear.htm

Dan

Yeah, well - he is hardly unbiased, though he pretends to be. Note that the oil that performed the best in HIS TEST is one of his sponsors - and it's an oil very few have heard of.

And, he dredged out the generic 'spin a bearing and apply a bunch of force on it' test. Geez - I think I saw that ploy on a Duralube commerical. There is a reason there are bearing clearances between the bearing and the crank. THAT'S where the oil goes, and it's supposed to be under pressure to keep the oil film in play. His simulation breaks a bunch rules that will not ever occur in a real engine.

His picture of a rod bearing that is worn at the top (which he indicated is caused by the oil squeezing out) is another common sales ploy. Hell, that could have easily come out of an engine that overheated or was detonating - or just low on oil.

I have rebuilt a BUNCH of engines - Hondas, Fords, etc - and NEVER saw that kind of wear on a well maintained engine even with 200k+ miles with good ole dyno juice. The cam lobes where shot to hell though. And the couple of rebuilds I've done on synthetic oiled cars (I think it was Mobil1) looked great internally (had they not overheated and blown the head gasket!). Anecdotal though.

I realize that the following is also anecdotal, but consider this:

GM picked Mobil1 for the vette. Ok, perhaps not a good example. Porsche could use ANY oil they damn well want no matter the cost (what's a $100 oil change to a Porsche purist!). They also picked Mobil1.

Any synthetic that meets SAE specs will be better than dyno oil under extreme conditions. But I still see very little hard evidence that any one synthetic is significantly better than another.


Venomous Mofo: If you drove around for 10,000 miles with a severe rod knock, more power to ya (on one oil change?). Hey, anything is possible. Just very, very unlikely the bearing was spun the entire time. More likely the knock got louder to the point you finally pulled the motor. Weren't you worried that the rod was going to air out the block? And it is VERY unlikely Mobil1 that did it. Something else happened - overheated, detonation, lack of oil, contaminated oil - a thousand causes, not all obvious.

-Dave

 

Forgot to mention. Before the Cobra, I also owned a '01 Porsche Boxster that came from the factory with Mobil1. More interesting was the mileage for the first scheduled maintenance, 15,000. Yep, that's right, Porsche fills their cars with Mobil1 out of the show room and tells you not to come back until 15,000 miles.

Again, if you read the specs on both oils, especially viscosity rating, the Mobil1 was much higher rated. I am told by a mechanic who knows much more than I do that this rating is a good indication of how good a lubricant the oil really is.

 

Yeah, well - he is hardly unbiased, though he pretends to be. Note that the oil that performed the best in HIS TEST is one of his sponsors - and it's an oil very few have heard of.



-Dave

I noticed that too. By all accounts, Shaeffer is the best oil in the world. I wonder why I haven't heard of it until reading bobistheoilguy.com ? Government conspiracy perhaps? Maybe they also make the cars that run on water and get 1,000 miles to the gallon.