Do you really need any thicker than 0W-20?

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Originally Posted By: CATERHAM
Originally Posted By: Trav
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Saying that you can't run a 2.6cP 20wt oil (or even something lighter) in an engine implies that you can't maintain adequate OP. Because if you can maintain the previously established safe minimum OP then by definition you are maintaining an adequate operational oil viscosity
That makes the assumption that a 2.6 cP oil is enough to protect a high HP/output engine under all conditions it might encounter. The Europeans don't seem to have much faith in this theory, most of their oil for these engines are HTHS 3.5+. You can say i am over thinking this but i would say you are under estimating the importance of HTHS and block/crank rigidity and the boundary film offered by higher HTHS oils in engines that by design require it. Marine engines are a perfect example of the necessity of stiff blocks and bottom end. GM in this case has gone to great lengths to stiffen the bottom end. http://gmpowertrain.com/2013_pdf/FHR_REV_6.0_Marine_010713.pdf My question to you is why do they bother going to 6 bolt mains and super stiff block if the most relevent criteria is maintaining oil pressure with an oil of 2.6 cP? Like i said i have no problems whatsoever using xw20 or xw16w oils in engines designed for them but they are putting warnings out for the xw16 oils about backwards compatibility. Why is that if the xw16 with less than 2.4 cP couldn't be used in any engine as long as they can maintain oil pressure? Could it be that unless the engine was specifically designed for this oil a less than 2.4 cP isn't enough to protect the engine? Couldn't the same be said for a 2.6 cP oil in an old school engine? I believe it could. I guess you and i will have to agree to disagree on this magical 2.6 CP number is able to provide optimal engine protection in any engine under any conditions.
There are many reasons why heavier oil grades are specified by some manufacturers but that is a separate question to your original point that, "Adding an oil pressure gauge is not a bad thing it is just not going to give you enough information under all conditions." What I've tried to explain is that statement is simply not true. An OP gauge (in conjunction with an oil temp' gauge for very high temp's) will tell you what you're operational viscosity is in a running engine; nothing else will. What an OP gauge will not do is tell what OP level is too low if that info hasn't already been determined. Your original comment about an OP gauge not being able to pick up crank flex is immaterial since that is not the purpose of an OP gauge. But if you knew that the operational viscosity level associated an OP level of say 45 psi did allow metal to metal contact under maximum load when crank flex occurred and that 50 psi didn't, then an OP gauge would be a very useful tool indeed to establish and maintain the minimum operational viscosity requirements to deal with that particular issue. Every engine has a safe minimum operational viscosity that can be readily established; the manufacturers OP test spec's are a good place to start.If one is going to experiment with different oil viscosities I know of no other way to keep track of where you're at than with the use of OP and OT gauges. You could drop down an oil grade to a 20wt from a 30 wt, run a UOA and get a good result but it still wouldn't tell you what you're really doing in terms of actual operational viscosity; you're still experimenting blind. Did you test the OEM OP test spec's and if you did how often and under what conditions? When you thought the engine oil must have been really hot on that 100F up hill climb, was it really? It's OP and OT gauges that tells you what really going on.
What i put in bold is where you and i are having a problem. I was responding to the question of High HP or modified engines. Let me give you an example. GM3800 GENII stock, manufacturer publish a spec and with an oil pressure and temp gauge i agree you can use that as a starting point, no problem. I am in full agreement with you so far. But now add a forged crank, high volume pump, bigger cam with modified heads and a 16 psi turbo. now what? The manufacturers spec just went out the window for the most part. So lets say i have both gauges and everything looks good on 5w30 then coming of an highway on ramp i hammer it. There is no way from the guages for me to know if the crank hit the bearings or not. IMHO this is the correct way to get around this issue. By all means keep the gauges but go up a weight from OEM spec like Mobil 1 0w40 or 5w40 make sure the op and temp are good, then do a UOA and another to see which way the wear metals are going. Do quite a few UOA's so you can see a real trend not just a one off from break in. That's the only i know f to find out if lead or aluminum is being shed from the bearings. If the UOA's are good then i see no point in going thinner, why mess with a good thing but if they show wear is excessive then decide which way to go or what to do to fix the issue. I see no way the gauges could provide me all the info i need to base my oil decision on without multiple UOA's in this engine. High spring weights, double roller chain and huge crank shock loads are sure to play havoc with the oil.
 
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I am not disagreeing with the fact, that both gauges are a big help but, do they really tell you what is happening to the bearings, rings and cylinders? I don't think the gauges could provide that info w-o uoa or ripping down an engine. Didn't we have a member who used to post here that lost an engine with all the gauges mentioned here and uoa info to back up that everything was all fine and dandy? Thicker isn't always bad the way some guys think. trav still has a valid argument I think. What happens when one of these thin high vi oils breaks down under high stress? I'd be wishing for a lower vi slightly thicker oil I think.
 

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Originally Posted By: Clevy
The new engine has a high volume oil pump however all clearances were kept stock.
I'd ditch the HV oil pump. It is just going to heat the oil, wear out your dist gear and steal power. The stock oil pump in a Windsor is MORE than adequate. I have no idea why so many people are obsessed with the idea of putting HV oil pumps in them, then running 20w-50 and being all "I've got 80psi of oil pressure, YEEEE HAAAAWWWWW" and then licorice-stick their oil pump drive shaft and nuke their engine. You go Cletus!!! LOL!!
 

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Originally Posted By: Clevy
However if a thin oil can be kept cool enough to maintain a thicker film on moving parts and thinner oil means the pump can move more volume which also helps keep bearings cooler and thinner oil can take heat away faster as well.
It will only move more volume if the oil pump has gone into bypass at the same volume with a heavier oil. Remember, oil pumps are positive displacement, for a given pump RPM, as long as the bypass isn't open, the system is going to see the same amount of oil be it 10w-60 or 0w-20.
 

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Originally Posted By: Trav
But now add a forged crank, high volume pump, bigger cam with modified heads and a 16 psi turbo. now what? The manufacturers spec just went out the window for the most part. So lets say i have both gauges and everything looks good on 5w30 then coming of an highway on ramp i hammer it. There is no way from the guages for me to know if the crank hit the bearings or not.
And this sounds exactly like the issue BuickGN was having. He tried 5w-50 and other oils in his GN and ended up lunching bearings. 20w-50 was what served him the best IIRC. The bottom-end on those engines, at his power level, move around a lot and he simply didn't have the film thickness, despite what the oil pressure gauge said, to protect the bearings from shock loads when he got on the loud pedal and into the boost.
 

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Originally Posted By: ADFD1
I am not disagreeing with the fact, that both gauges are a big help but, do they really tell you what is happening to the bearings, rings and cylinders? I don't think the gauges could provide that info w-o uoa or ripping down an engine. Didn't we have a member who used to post here that lost an engine with all the gauges mentioned here and uoa info to back up that everything was all fine and dandy? Thicker isn't always bad the way some guys think. trav still has a valid argument I think. What happens when one of these thin high vi oils breaks down under high stress? I'd be wishing for a lower vi slightly thicker oil I think.
That was BuickGN. He even had relatively normal UOA's on the engine when it was self-destructing because the particles being shed were too large to be picked up by a UOA.
 
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Originally Posted By: OVERKILL
Originally Posted By: Clevy
The new engine has a high volume oil pump however all clearances were kept stock.
I'd ditch the HV oil pump. It is just going to heat the oil, wear out your dist gear and steal power. The stock oil pump in a Windsor is MORE than adequate. I have no idea why so many people are obsessed with the idea of putting HV oil pumps in them, then running 20w-50 and being all "I've got 80psi of oil pressure, YEEEE HAAAAWWWWW" and then licorice-stick their oil pump drive shaft and nuke their engine. You go Cletus!!! LOL!!
You sound just like my father! Kudos to you. I see you like Mobil 1 0W40, I bet you have good reason for that too. You live in Canada, I don't think you're too worried about cold start wear either with that super oil are you?
 
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Originally Posted By: OVERKILL
Originally Posted By: ADFD1
I am not disagreeing with the fact, that both gauges are a big help but, do they really tell you what is happening to the bearings, rings and cylinders? I don't think the gauges could provide that info w-o uoa or ripping down an engine. Didn't we have a member who used to post here that lost an engine with all the gauges mentioned here and uoa info to back up that everything was all fine and dandy? Thicker isn't always bad the way some guys think. trav still has a valid argument I think. What happens when one of these thin high vi oils breaks down under high stress? I'd be wishing for a lower vi slightly thicker oil I think.
That was BuickGN. He even had relatively normal UOA's on the engine when it was self-destructing because the particles being shed were too large to be picked up by a UOA.
That was my point, his gauges and uoa reports painted a very pretty picture, and boom went the engine. My point is even though they are great tools to have they obviously don't tell the whole truth, nothin' but the truth do they?
 
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Originally Posted By: ADFD1
Originally Posted By: OVERKILL
Originally Posted By: ADFD1
I am not disagreeing with the fact, that both gauges are a big help but, do they really tell you what is happening to the bearings, rings and cylinders? I don't think the gauges could provide that info w-o uoa or ripping down an engine. Didn't we have a member who used to post here that lost an engine with all the gauges mentioned here and uoa info to back up that everything was all fine and dandy? Thicker isn't always bad the way some guys think. trav still has a valid argument I think. What happens when one of these thin high vi oils breaks down under high stress? I'd be wishing for a lower vi slightly thicker oil I think.
That was BuickGN. He even had relatively normal UOA's on the engine when it was self-destructing because the particles being shed were too large to be picked up by a UOA.
That was my point, his gauges and uoa reports painted a very pretty picture, and boom went the engine. My point is even though they are great tools to have they obviously don't tell the whole truth, nothin' but the truth do they?
UOA are great "tools" They do not replace engine tear downs to see how internals are however.
 

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Originally Posted By: ADFD1
You sound just like my father! Kudos to you. I see you like Mobil 1 0W40, I bet you have good reason for that too. You live in Canada, I don't think you're too worried about cold start wear either with that super oil are you?
I'm hoping sounding like your dad is a good thing grin Though from your post, I'm thinking it is smile Yes, I'm very fond of the "Nectar of the Gods" M1 0w-40, which I've run in many vehicles/engines, including a number of high-mileage Windsor's. It is my oil of choice for that application and many others. The Windsor and the modular have a difference between them that Trav touched-on, though not in the context of those engine families. When you look at the bottom-end of a Modular, it has a deep-skirted block with multi-bolt (and side-bolt) main caps. Things aren't moving around on you with this setup. It also has a gyrator style oil pump, which moves a lot more oil, and at a very high pressure. When you look at the bottom-end of a Windsor, you have your typical thin-wall cast non-skirted 2-bolt main lightweight V8. Things ARE moving around on you with this setup. The block flexes, the caps move....etc. When you start to turn up the wick on these two engine families, that difference with respect to bottom-end rigidity is relevant. And may not be something you are going to see on an oil pressure gauge. This makes suggestions like Trav's (and one I echo) which is to start with an oil like M1 0w-40 and see if your pressure is consistent, if your magnet stays clean, that you don't accrue excessive particulate in the filter, and that you don't have stand-outs in your UOA's SAFER than starting with something thin and working your way up. Because once damage happens, it isn't like you can just "take it back". For a Windsor, M1 0w-40, being on the thin side of the 40-scale, is a bit heavier than Ford's recommendation of 10w-30, and, in my experience, has been shown to provide exceptional protection at higher than stock power levels. Guys that run a blower, which heats that 5 quart sump even more, and often share the oil with the engine, usually run something even heavier, like 5w-50. But oil and coolant temperatures are also elevated in these applications, so this is a natural progression in terms of going heavier to account for that.
 

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Originally Posted By: DragRace
Originally Posted By: ADFD1
Originally Posted By: OVERKILL
Originally Posted By: ADFD1
I am not disagreeing with the fact, that both gauges are a big help but, do they really tell you what is happening to the bearings, rings and cylinders? I don't think the gauges could provide that info w-o uoa or ripping down an engine. Didn't we have a member who used to post here that lost an engine with all the gauges mentioned here and uoa info to back up that everything was all fine and dandy? Thicker isn't always bad the way some guys think. trav still has a valid argument I think. What happens when one of these thin high vi oils breaks down under high stress? I'd be wishing for a lower vi slightly thicker oil I think.
That was BuickGN. He even had relatively normal UOA's on the engine when it was self-destructing because the particles being shed were too large to be picked up by a UOA.
That was my point, his gauges and uoa reports painted a very pretty picture, and boom went the engine. My point is even though they are great tools to have they obviously don't tell the whole truth, nothin' but the truth do they?
UOA are great "tools" They do not replace engine tear downs to see how internals are however.
BINGO thumbsup
 
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Originally Posted By: OVERKILL
Originally Posted By: Trav
But now add a forged crank, high volume pump, bigger cam with modified heads and a 16 psi turbo. now what? The manufacturers spec just went out the window for the most part. So lets say i have both gauges and everything looks good on 5w30 then coming of an highway on ramp i hammer it. There is no way from the guages for me to know if the crank hit the bearings or not.
And this sounds exactly like the issue BuickGN was having. He tried 5w-50 and other oils in his GN and ended up lunching bearings. 20w-50 was what served him the best IIRC. The bottom-end on those engines, at his power level, move around a lot and he simply didn't have the film thickness, despite what the oil pressure gauge said, to protect the bearings from shock loads when he got on the loud pedal and into the boost.
If i remember right he even got good UOA's back before he had a pan full of scrap metal. Edit: I must be asleep at the switch someone already posted this. LOL
 
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Originally Posted By: Trav
If i remember right he even got good UOA's back before he had a pan full of scrap metal.
He did, and all the gauges in the world weren't going to help him.
 
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Originally Posted By: ADFD1
I am not disagreeing with the fact, that both gauges are a big help but, do they really tell you what is happening to the bearings, rings and cylinders?
Agreed...the gauges are measuring sump temperature and the pressure in the main oil gallery in the engine. As I've stated previously, from that main gallery, oil passes through : * Main bearings (turning at crank speed) * Cam bearings (turning at half speed), and speed is one of the key design parameters in the lubrication regime of bearings. * Oil squirters (generally multiple), which depending on their design, may be measuring kinematic viscosity (long pipes), or density (orifices) * Rod Bearings... (Go back to the bearing tutorials earlier in the thread, and see the difference in rotational speed has on lubrication.) All of these items are in parallel (bar the rod bearings), so Caterham's OP gauge is measuring the resistance to flow across all of them, as an average. So asserting that each of these points is lubricated adequately by having pressure is false, it's a real good guess, I guess. The sump temperature is the average of the temperature rises across each of these areas. Bearings have measured and calculated temperature rises of 10s of degrees Celsius. Caterham has refuted that as "not feeling right" in the past, but it's fact. It doesn't "feel" right to a person watching a temperature gauge, as the sump temp is the average of bearing temperature rises (tens of degrees), piston squirter temperature rises (not much to some depending on design), and chain squirters (not much rise),and oil pump bypass temperature rise (should not happen, as I agree it's wasted power, and unnecessary heat). Sump temp doesn't tell you exactly what is going on in any of the bearings, but I agree, you can gain a "feeling" that things are generally good, or turning to whoop...It's not a scientific, empiracle proof that all is good. Now getting back to the rod bearings. They are fed oil from oil that's already been through the crank bearings, have picked up heat (aforementioned tens of degrees C), lost pressure, lost viscosity, and reallyhave no direct connection to the main gallery pressure gauge, nor have the operating temperature monitored as the rise is diluted by all of the other feeds back into the sump. Rod bearings are operated in a highly cyclic load pattern, which is difficult to design for anyway. Main bearing viscometer may or may not reflect adequacy of lubrication in the rod bearings. OT, I think that the hot, atomised oil being flung out of rod bearings, being first contact with piston blowby gasses is probably the most likely place for varnish to be created in an engine. Hypothesis that I'm working on at present.
 
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Originally Posted By: Trav
Originally Posted By: CATERHAM
Originally Posted By: Trav
Quote:
Saying that you can't run a 2.6cP 20wt oil (or even something lighter) in an engine implies that you can't maintain adequate OP. Because if you can maintain the previously established safe minimum OP then by definition you are maintaining an adequate operational oil viscosity
That makes the assumption that a 2.6 cP oil is enough to protect a high HP/output engine under all conditions it might encounter. The Europeans don't seem to have much faith in this theory, most of their oil for these engines are HTHS 3.5+. You can say i am over thinking this but i would say you are under estimating the importance of HTHS and block/crank rigidity and the boundary film offered by higher HTHS oils in engines that by design require it. Marine engines are a perfect example of the necessity of stiff blocks and bottom end. GM in this case has gone to great lengths to stiffen the bottom end. http://gmpowertrain.com/2013_pdf/FHR_REV_6.0_Marine_010713.pdf My question to you is why do they bother going to 6 bolt mains and super stiff block if the most relevent criteria is maintaining oil pressure with an oil of 2.6 cP? Like i said i have no problems whatsoever using xw20 or xw16w oils in engines designed for them but they are putting warnings out for the xw16 oils about backwards compatibility. Why is that if the xw16 with less than 2.4 cP couldn't be used in any engine as long as they can maintain oil pressure? Could it be that unless the engine was specifically designed for this oil a less than 2.4 cP isn't enough to protect the engine? Couldn't the same be said for a 2.6 cP oil in an old school engine? I believe it could. I guess you and i will have to agree to disagree on this magical 2.6 CP number is able to provide optimal engine protection in any engine under any conditions.
There are many reasons why heavier oil grades are specified by some manufacturers but that is a separate question to your original point that, "Adding an oil pressure gauge is not a bad thing it is just not going to give you enough information under all conditions." What I've tried to explain is that statement is simply not true. An OP gauge (in conjunction with an oil temp' gauge for very high temp's) will tell you what you're operational viscosity is in a running engine; nothing else will. What an OP gauge will not do is tell what OP level is too low if that info hasn't already been determined. Your original comment about an OP gauge not being able to pick up crank flex is immaterial since that is not the purpose of an OP gauge. But if you knew that the operational viscosity level associated an OP level of say 45 psi did allow metal to metal contact under maximum load when crank flex occurred and that 50 psi didn't, then an OP gauge would be a very useful tool indeed to establish and maintain the minimum operational viscosity requirements to deal with that particular issue. Every engine has a safe minimum operational viscosity that can be readily established; the manufacturers OP test spec's are a good place to start.If one is going to experiment with different oil viscosities I know of no other way to keep track of where you're at than with the use of OP and OT gauges. You could drop down an oil grade to a 20wt from a 30 wt, run a UOA and get a good result but it still wouldn't tell you what you're really doing in terms of actual operational viscosity; you're still experimenting blind. Did you test the OEM OP test spec's and if you did how often and under what conditions? When you thought the engine oil must have been really hot on that 100F up hill climb, was it really? It's OP and OT gauges that tells you what really going on.
What i put in bold is where you and i are having a problem. I was responding to the question of High HP or modified engines. Let me give you an example. GM3800 GENII stock, manufacturer publish a spec and with an oil pressure and temp gauge i agree you can use that as a starting point, no problem. I am in full agreement with you so far. But now add a forged crank, high volume pump, bigger cam with modified heads and a 16 psi turbo. now what? The manufacturers spec just went out the window for the most part. So lets say i have both gauges and everything looks good on 5w30 then coming of an highway on ramp i hammer it. There is no way from the guages for me to know if the crank hit the bearings or not. IMHO this is the correct way to get around this issue. By all means keep the gauges but go up a weight from OEM spec like Mobil 1 0w40 or 5w40 make sure the op and temp are good, then do a UOA and another to see which way the wear metals are going. Do quite a few UOA's so you can see a real trend not just a one off from break in. That's the only i know f to find out if lead or aluminum is being shed from the bearings. If the UOA's are good then i see no point in going thinner, why mess with a good thing but if they show wear is excessive then decide which way to go or what to do to fix the issue. I see no way the gauges could provide me all the info i need to base my oil decision on without multiple UOA's in this engine. High spring weights, double roller chain and huge crank shock loads are sure to play havoc with the oil.
Gauges are just going to tell you what your operational viscosity is, not how much viscosity is required especially in a modified engine, that's an entirely separate issue. That said, the Joe Gibbs chart I referenced does give a viscosity guide for American performance engines based largely on bearing clearances and expected maximum oils temp's.
 
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Originally Posted By: Caterham
Gauges are just going to tell you what your operational viscosity is, not how much viscosity is required especially in a modified engine, that's an entirely separate issue.
Agree 100% with that. A stock engine that specs multiple viscosities depending on location and use can no doubt use the gauges to find the optimal operating viscosity for the conditions its driven under.
 
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Originally Posted By: Clevy
Originally Posted By: Chilaka
Hi All...sorry to deviate a little. I've read about checking the pressure of the engine to determine what oil is right for you. I subscribe to the idea, the only challenge is that my ride Civic 2002 Ex at 160,000miles and still riding well only has the rpm indicator. So how do I get to determine the oil or engine psi at say 2000 rpm.
You would have to buy aftermarket gauges and have them installed. You need oil temp and oil pressure. I suggest looking at eBay. My mustang has a 2 and 3 gauge cluster that can be put on the a pillar and just replaces the trip piece. Perhaps you can find something similar for your car.
I noticed some discussion on engine tuneing, shaft forging and all. My engine is still the stock 1.7 vtec engine that comes with a Honda Civic 2002 Ex, that side I suppose I should be fine wthe the aftermarket gauges showing oil temp and pressure. Please what after market brand would you advice I go for? Thanks a lot.
 

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Originally Posted By: Chilaka
Originally Posted By: Clevy
Originally Posted By: Chilaka
Hi All...sorry to deviate a little. I've read about checking the pressure of the engine to determine what oil is right for you. I subscribe to the idea, the only challenge is that my ride Civic 2002 Ex at 160,000miles and still riding well only has the rpm indicator. So how do I get to determine the oil or engine psi at say 2000 rpm.
You would have to buy aftermarket gauges and have them installed. You need oil temp and oil pressure. I suggest looking at eBay. My mustang has a 2 and 3 gauge cluster that can be put on the a pillar and just replaces the trip piece. Perhaps you can find something similar for your car.
I noticed some discussion on engine tuneing, shaft forging and all. My engine is still the stock 1.7 vtec engine that comes with a Honda Civic 2002 Ex, that side I suppose I should be fine wthe the aftermarket gauges showing oil temp and pressure. Please what after market brand would you advice I go for? Thanks a lot.
Autometer.
 

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I guess with my chromium value being high (5 ppm, even though it could be due to contamination during sampling), I wouldn't be able to draw a definite conclusion on adequacy of 0W-20 for my engine. Current fill is Toyota 0W-20 SN also. Perhaps I should go back to Mobil Delvac 1300 Super 15W-40 for the next fill (I still have a jug) and have a UOA comparison. I might wait for another fill just to eliminate contamination concerns though. Thick vs. thin is certainly an unresolved debate.
 
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