Bob the oil guy website guidlines

[madmaxx]

I have read BTOG website and if correct he recommends the following for oil viscosity.

1) 10 psig per 1000 rpm at operating temp. Oil which generates pressure any higher is detrimental.
2) No oil on the market regardless of weight is thin enough for cold start-up. Everyone should be using 0W-??? The caveat is it must be synthetic.
3) Dino oil starts off as the low number in the oil designation. For example 10W30, 10W40 all start as 10W and polymers are added.
4) All synthetic oil starts off as the higher number. For example 0-30, 5w30, 10w30 are all 30wt oil. Synthetic does not need viscosity improvers like dino oil.
5) 99% of the population should be using 0w20, and the other 0W30. He recommends no 20W50 etc. He said in an older engine you might want to use Mobil 1 0W40 to compensate for wear and it has higher phosphorous and zinc level than other oils. 1,000 and 1100 respectively.
6) You need the extra zinc/phosphorous in high hp applications regardless of roller cam or not. Examples of worn connection rod bearings were found, especially the top half.

Just thought I would share. Working a turnaround and 14 hrs days get boring but the $$$$$$ is good

[Bob In Ct]

Who made Bob the oil expert?

For me it's nine quarts of 5W-30 Redline (1,200 PPM ZDDP) plus 4 ounces of Redline ZDDP additive which gets me to about 1,450 ZDDP.

I've been running 55 PSI hot at 2,000 RPM for 10 years now with no problems.

Bob (not the oil guy)

[madmaxx]

I think BTOG would be thrilled with your selection. 5W30 and ZDDP additive, you are dead on with his recommendations. I beleive the 10 psig is at redline so if you readline at 6K rpms what is your oil pressure.

Originally Posted by Bob In Ct

Who made Bob the oil expert?

For me it's nine quarts of 5W-30 Redline (1,200 PPM ZDDP) plus 4 ounces of Redline ZDDP additive which gets me to about 1,450 ZDDP.

I've been running 55 PSI hot at 2,000 RPM for 10 years now with no problems.

Bob (not the oil guy)

[FWB]

i think if bob the oil guy ran a fe with factory steel crank and rods at the dragstrip turning 6800, bob the oil guy would be bob the grenade guy.

100 psi cold no more no less or bye bye rod bearings....competition proven since 1977....

[Excaliber]

It's an interesting web site, been around for awhile, often quoted on various car sites. The guy is a little controversial, has some good insight. I don't take everything he says as gospel, his 0 wieght oil for one.

Synthetics are NOT for good for every engine.
Ernie, the other oil guy.

[marco246]

The info posted by madmaxx came from the site BITOG (Bob Is the Oil Guy) but "Bob" had nothing to do with it. It was provided by a medical doctor named A.E. Haas who is not a tribologist and whose extensive views are not embraced by a large number of BITOG members. Dr. Haas does, however, put his money where his mouth is by running very low viscosity oils in very expensive cars. For example, he uses 0W-20 in his Ferrari Enzo. I believe the factory calls for 10W-60.

[madmaxx]

I did not know that all though I doubt BTOG would allow incorrect information. His reasoning appears sound. I played with some viscosity calculators at 40F 10W30 has a viscosity of 439cst! at 212F it is 10.7cst. 15W50 at 40F is 923 cst!!!, at 212 F it is 18. As you can see viscosity increases exponentially as the temperature lowers. Even 0W40 has a viscosity of 426 cst at 40F, just slighly lower than the 10W30.

I imagine any viscosity above 20 Cst and the oil pump bypasses due to the rv in the oil pump lifting. Not only do you have thicker oil, more is bypassing to the oil pan and not even reaching critical engine parts.

Originally Posted by marco246

The info posted by madmaxx came from the site BITOG (Bob Is the Oil Guy) but "Bob" had nothing to do with it. It was provided by a medical doctor named A.E. Haas who is not a tribologist and whose extensive views are not embraced by a large number of BITOG members. Dr. Haas does, however, put his money where his mouth is by running very low viscosity oils in very expensive cars. For example, he uses 0W-20 in his Ferrari Enzo. I believe the factory calls for 10W-60.

[Excaliber]

I doubt BTOG would allow incorrect information.

Bob offer's his opinions, backs it with some research, some facts, but in the end it is neither correct nor incorrect. It's an opinion, one which is not shared by the auto manufacturers, for some reason. Maybe THEY are "incorrect"?

I ran synthetic in my FE for a short while. It pretty much leaked or blew oil out every possible orifice. I think I'll stick with 20-50 thanks...

[RodKnock]

I agree with Ernie. We'll have another 10 pages of no answers and plenty of opinions.

[YerDugliness]

Originally Posted by Excaliber

I ran synthetic in my FE for a short while. It pretty much leaked or blew oil out every possible orifice. I think I'll stick with 20-50 thanks...

Isn't that what FE's just seem to do in general ?

......at least that's the word on the street .

Cheers from Dugly

[Excaliber]

Well I did blow some oil out of the valve cover vent recently and was running 20-50.

But wait, there's more!!! That was at SAAC-35 on the track. I wanted to try out 2nd gear at max rpm through a couple of corners, just to see how the motor liked that, or didn't like it. I was fully prepared to accept it might blow. It didn't! Man that thing was rocking and NOT knocking! Ye Haw, awesome running 5500-6500 rpm through those corners,,, uh,,, thats when I noticed the smoke. I was running about a half quart over full (for the corner issues with oil moving or whatever) and it got some oil on the headers.

I thought I was in trouble, but no big deal, wiped it down and ran third the rest of the weekend.

Pretty much fried the rear brakes though, got to get some ventilation going for those inboards.

[madmaxx]

I posted to help educate myself. I am trying to determine the correct viscosity for my engine. I know the manufacturer recommends, 10W30 but everyone here likes the 20W50. My oil pressure is 53 psig anything above 1500 rpms but at idle is get to about 30 psig with the 10W30 at 100c oil temp. It appears eveyone on this site likes to see 45 psig at idle. Who know who is right????

[Excaliber]

Rumor has it NASCAR folks like low oil pressure, less parasitic loss from the oil pump so they keep it at "just enough" to do the job. I suspect the rule of thumb of 10 psi per thousand rpm is valid.

But for myself, I'm not trying to eek out every last fraction of a horse power by reducing my oil pressure. While 10 per thousand may be OK I don't have a problem with twice that, or whatever.

TO much oil pressure COULD be a problem how ever. Extra stress on the oil pump drive shaft has been known to twist and break them! Over a certain amount and the oil by-passes the oil filter. If you are running "high pressure" it's certainly important to keep the rpm low to reasonable until it warms up.

We ran 50 wt. in the Formula Fords, but were careful to keep the rpm low until the oil warmed up. I don't have a problem with 30 psi at idle at 100 c myself, 45 is not some magic number.

Another reason I don't care for synthetic oil is the long oil change intervals usually recommended. My position has remained unchanged for decades on this subject, in spite of "new studies". People ask what oil I prefer, I tell 'em, use a good quality brand name and STICK WITH IT and change it often.

[vector1]

my hot idle oil pressure is probably less then 25# on a 351w with an external pump, but increases with engine rpm. i've read it takes very little pressure at idle to keep the bearings happy. cold with 10w30 idle is 45 & 75 at higher rpm probably going into bypass. hot is <25 and goes to 50+ pretty quick as rpm increases.

[Bob In Ct]

It's too bad we only have oil pressure gauges. If we had an oil flow gauge many of us would be using a less viscous oil. What good is 80 PSI if it's not moving?

Bob

[madmaxx]

If the oil pump is a positive displacement pump then flowrate at the discharge of the pump is always the same for a given rpm up to its releif valve setting. Once the relief valve lifts it is recirculating back to the pan.

I guess I see the advantage of heavier oil is the boundry layer between the piston skirts and cylinder walls, bearings surfaces etc are thicker ensuring no metal to metal contact. This assumes the component gets oil to begin with.

It would appear if you like heavier oil Mobil 1 15W50 may be the answer since it has the 1200 and 1300 ppm of phosphorous and zinc.

Thanks for all the replies.

Originally Posted by Bob In Ct

It's too bad we only have oil pressure gauges. If we had an oil flow gauge many of us would be using a less viscous oil. What good is 80 PSI if it's not moving?

Bob

[Ant]

BTOG has a lot of information and like a lot of us is on a quest for the best oil for our applications.
These statements like 0-40 for our engines is just BS.
Use the oil that has is built for eg flat tappet camshafts normally a race oil that can be used on the street etc etc.
My Toyota Vitz 1000cc they recommend 5w30 so I use Castrol Edge 5w30 full synthetic as I travel 100 miles round trip to work.

I am going to use Schaeffer 20-50 race oil in my Cobra and it will be heated in the oil tank before use. I use what my engine builder recommends and what the leading race guys are using plus Schaeffer oil is recommended for extended oil changes. Schaeffer oil has excellent start up properties, the only minor detail might be a slight hp loss due to being thicker, I would prefer to have the protection when hot and under hard use. For the road I would use Chevron 400 15w40 as I know people that have done 300,000miles in petrol engines still going strong this oil is made for diesel and petrol engines.

[madmaxx]

What is the justification for 0w40 recommendation being BS, viscosity at 30F is THICKER than 10W30?

at 90F 10W30 is 92cst and Ow40 is 102cst so OW40 is thicker than 10W30 at lower and higher temperatures.

[Ant]

YOUR QUOTE:
5) 99% of the population should be using 0w20, and the other 0W30. He recommends no 20W50 etc. He said in an older engine you might want to use Mobil 1 0W40 to compensate for wear and it has higher phosphorous and zinc level than other oils. 1,000 and 1100 respectively.

No exactly BS, He did say might want to use, but a lot of engine builders who also race their product tend to stick to certain viscosities with mainly V8 engines designed in the 1960's, that of course doesnt mean you cant reduce startup wear with a 0w-40 oil and of course if that oil does the job hot and also has the right makeup of additives for flat tappet camshafts then no problem.

Castrol and several other oil companies make specific oils for old technology engines, they tend to be 20w50 or thicker, I guess this takes into account fuel polution etc contaminating and diluting the oil so in race engines start off thicker......! For road use Mobil 1 0w-40 might be great but reading the applications for the 0w grades the oil manufacturer specifies these grades for modern small engines and larger engines the heavier grades.

I am still not sure what to exactly use as this car is going to be road driven as well, and like a lot of others on this forum I would prefer to see Schaeffer make a 10w50 as I think 20w oil is too thick when cold, hence I will heat first in colder climates.

[vector1]

changing my oil out and think i am going to use mobil 1 delvac 1300, 15w40. diesel engine oil.