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yeah it is definitely not ground breaking in terms of design but from what I have found these gauges are very accurate and very well built. Apparently a lot of their devices are used in high end cappuccino machines in a commercial environment.
i have an alarm clock on wheels that when it goes off it rolls off the nightstand and starts running around the room til you catch it---works every time!
OD
i have an alarm clock on wheels that when it goes off it rolls off the nightstand and starts running around the room til you catch it---works every time!
OD
That's a cool Alarm Clock!! I bet you are well awake after you catch it.
yeah it is definitely not ground breaking in terms of design but from what I have found these gauges are very accurate and very well built. Apparently a lot of their devices are used in high end cappuccino machines in a commercial environment.
so if you install one of these your 8 will smell like cappuccino every day ?
__________________
2005 Shinka RX-8, First engine died @ 48303 miles, replaced with Mazda's Reman by Kevin @ Wayne Mazda.
1991 RX-7 S5 FC3S -- Doing an EXTREME makeover NYCGPS edition right now.
i have an alarm clock on wheels that when it goes off it rolls off the nightstand and starts running around the room til you catch it---works every time!
OD
I saw this alarm clock awhile ago. It is very ingenius.
so if you install one of these your 8 will smell like cappuccino every day ?
Well, to quote Jeremy Clarkson when he reviewed the RX-8; "The car doesn't feel like it's running on something as coarse and vulgar as petrol... It feels like it's running on double cream!"
Olddragger sold me on Rotella 15-40 diesel oil, so I've been running that in AZ the past couple of months. I know that the thinking goes that you need the cold viscosity # at at least 15, or the hot # will break down too early as the additives wear out. But, I also know that the diesel aspect has been critical in preventing viscosity breakdown in oil tests done by Olddragger (and someone else here recently confirmed almost the exact same results). My question is, in those tests the 15-40 diesel was compared against 5-30 and 10-40. Have tests been done w/ non-diesel 15-40? I'd be curious to see the comparison. Perhaps the more important factor is the anti-foaming and additional detergents, vs. the high cold #. Are there any good diesel oils that start with a cold viscosity of 10w and have either 40 or 50 as the hot weight?
Why would you run 15-40 when you could run 0-40 or 5-40 synthetic??
I get the diesel oil has different additive pacs...with more foam suppressants and dispersants for the "dirty" diesel combustion.....
You want the high number high...and the low # as low as possible....
Because, ideally, a 0-50 like Eneos would stay as such. However, to achieve the larger spread between the weights, the oil is using larger amounts of additives to achieve that spread. And the reality is that those additives break down, and especially faster in an engine that runs at higher temps like a rotary (even with full synthetics). So, when the additives break down, a 50 operating temp viscosity, quickly drops to 40, 30, etc. But if your cold viscosity weight starts at 15, then the same breakdown in additives now reduce the viscosity to a proportionally smaller degree.
Also, I'm not sold on using an oil that starts at 0 weight. It's possible that that is too thin for the tolerance specs of the Renesis, causing leaking of oil through the seals.
because, ideally, a 0-50 like eneos would stay as such. However, to achieve the larger spread between the weights, the oil is using larger amounts of additives to achieve that spread. And the reality is that those additives break down, and especially faster in an engine that runs at higher temps like a rotary (even with full synthetics). So, when the additives break down, a 50 operating temp viscosity, quickly drops to 40, 30, etc. But if your cold viscosity weight starts at 15, then the same breakdown in additives now reduce the viscosity to a proportionally smaller degree.
Also, i'm not sold on using an oil that starts at 0 weight. It's possible that that is too thin for the tolerance specs of the renesis, causing leaking of oil through the seals.
Also a quote from a very knowledgeable petrochemical engineer........
" In high-speed bearings the oil can be too thick to keep up with the high rubbing speeds reached in modern engines so the ‘wedge’ or hydrodynamic’ effect breaks down. I know it goes against common sense (whatever that is) but the faster a bearing is turning the thinner the oil should be. (A 4cm. diameter main bearing is rubbing its shells at 56 MPH at 12,000RPM! To avoid cavitation the oil need to be less 10cSt or less, which is SAE 30 if the oil happens to be at 100C, or SAE 40 if its at 110C.))"
Because, ideally, a 0-50 like Eneos would stay as such. However, to achieve the larger spread between the weights, the oil is using larger amounts of additives to achieve that spread. And the reality is that those additives break down, and especially faster in an engine that runs at higher temps like a rotary (even with full synthetics). So, when the additives break down, a 50 operating temp viscosity, quickly drops to 40, 30, etc. But if your cold viscosity weight starts at 15, then the same breakdown in additives now reduce the viscosity to a proportionally smaller degree.
Also, I'm not sold on using an oil that starts at 0 weight. It's possible that that is too thin for the tolerance specs of the Renesis, causing leaking of oil through the seals.
It is not true.
A 0w-xx oil always has to be true synthetic, and a multi viscosity true synthetic oil's basic oil is always equal its warm side visc. So a 0w-50 has 50w basic oil, and it has additives to reach the 0w cold side. It means that a full syn oil doesn't thinning too much as the additives break down. It is rather thinning by fuel dillution.
The mineral base multi visc oil are on the opposite side. Those has the cold side weight base oil, and the additives help to get the warm side.
A 0w-xx oil always has to be true synthetic, and a multi viscosity true synthetic oil's basic oil is always equal its warm side visc. So a 0w-50 has 50w basic oil, and it has additives to reach the 0w cold side. It means that a full syn oil doesn't thinning too much as the additives break down. It is rather thinning by fuel dillution.
The mineral base multi visc oil are on the opposite side. Those has the cold side weight base oil, and the additives help to get the warm side.
Ayron is right about this. 10w-50 syn starts with 50 wt base oil, 10w-50 dino starts with 10 wt. base oil.
Thanks dannobre, I wasn't aware that full synths additives to achieve weight spread actually ran in the opposite direction of dinos. Good to know!
I'm still wary of running a 0 weight oil for fear of leaking through the seals.
As for what Nascar, F1, drag racers etc. run, that doesn't apply unless you only drive your 8 at the track, or are talking about what to run solely at the track, or if you plan on pulling over every 1/4 mile to swap all fluids.
Because, ideally, a 0-50 like Eneos would stay as such. However, to achieve the larger spread between the weights, the oil is using larger amounts of additives to achieve that spread. And the reality is that those additives break down, and especially faster in an engine that runs at higher temps like a rotary (even with full synthetics). So, when the additives break down, a 50 operating temp viscosity, quickly drops to 40, 30, etc. But if your cold viscosity weight starts at 15, then the same breakdown in additives now reduce the viscosity to a proportionally smaller degree.
Also, I'm not sold on using an oil that starts at 0 weight. It's possible that that is too thin for the tolerance specs of the Renesis, causing leaking of oil through the seals.
Spin you've got a lot of this backwards
Quote:
Originally Posted by ayrton012
It is not true.
A 0w-xx oil always has to be true synthetic, and a multi viscosity true synthetic oil's basic oil is always equal its warm side visc. So a 0w-50 has 50w basic oil, and it has additives to reach the 0w cold side. It means that a full syn oil doesn't thinning too much as the additives break down. It is rather thinning by fuel dillution.
The mineral base multi visc oil are on the opposite side. Those has the cold side weight base oil, and the additives help to get the warm side.
You guys are reading the numbers in a manner which isn't what they truely represent. It would be better off if they used letters instead.
In a multi-viscosity oil the oil is always thicker at room temperature than operating temperature. Instead of thinking that oil thins as it gets warmer you need to think that oil gets thicker as it cools. A 0w oil at room temperature is still going to be much thicker than at operating temperature.
A 0w-30, 5w-30, and 10w-30 all have the exact same viscosity at operating temperature. Their only major difference is their thickness at room temperature. A 0w oil is going to be the least thick while a 20w will be the most thick. Since the majority of wear occurs at startup (when there isn't any oil on the metal surface) you want the oil to flow as quickly and easily as possible.
Quote:
Originally Posted by dannobre
" In high-speed bearings the oil can be too thick to keep up with the high rubbing speeds reached in modern engines so the ‘wedge’ or hydrodynamic’ effect breaks down. I know it goes against common sense (whatever that is) but the faster a bearing is turning the thinner the oil should be. (A 4cm. diameter main bearing is rubbing its shells at 56 MPH at 12,000RPM! To avoid cavitation the oil need to be less 10cSt or less, which is SAE 30 if the oil happens to be at 100C, or SAE 40 if its at 110C.))"
This is 100% correct. While I have not been able to find any specific team mentions, I've seen information on several instances that Formula 1 cars use oils as thin as straight 10w oils. When they rev to 15,000+ rpms they need thinner oils.
__________________ Black Halo Racing - Butchers, Hacks, and Retards. I'm the hack! todd@blackhaloracing.com
Thanks dannobre, I wasn't aware that full synths additives to achieve weight spread actually ran in the opposite direction of dinos. Good to know!
I'm still wary of running a 0 weight oil for fear of leaking through the seals.
As for what Nascar, F1, drag racers etc. run, that doesn't apply unless you only drive your 8 at the track, or are talking about what to run solely at the track, or if you plan on pulling over every 1/4 mile to swap all fluids.
Why would you think it would leak through the seals........it is the same "thickness" at operating temp. Also....the punishment that a racing engine sees in an enduro length event is way more than your car would see in a long time.
Except for the starting/cold oil issues that racing engines don't have to endure.
There are so many misconceptions on oil out there...that's why all the old wives tales allow the petroleum industry to "con" people with the advertising
There are so many misconceptions on oil out there...that's why all the old wives tales allow the petroleum industry to "con" people with the advertising
It's all about the money guys
Again, right on the money. The two major "cons" that are employed are selling mineral oil as synthetic oil (higher profit) and also telling people they need to change their oil every 3,000 miles or their car will explode.
The oil change interval is pushed by manufacturers because it aid their warranty process. It helps oil manufacturers because they sell more oil!
Don't expect the oil companies to come out and correct all this misinformation. As long as people buy their products they don't care.
__________________ Black Halo Racing - Butchers, Hacks, and Retards. I'm the hack! todd@blackhaloracing.com
The oil change interval is pushed by manufacturers because it aid their warranty process. It helps oil manufacturers because they sell more oil!
And helps the dealers because they get you in the door for services...which is where they make most of there money....especially for the padding type items that are useless like oil flushes and brake cleaning
Also a quote from a very knowledgeable petrochemical engineer........
" In high-speed bearings the oil can be too thick to keep up with the high rubbing speeds reached in modern engines so the ‘wedge’ or hydrodynamic’ effect breaks down. I know it goes against common sense (whatever that is) but the faster a bearing is turning the thinner the oil should be. (A 4cm. diameter main bearing is rubbing its shells at 56 MPH at 12,000RPM! To avoid cavitation the oil need to be less 10cSt or less, which is SAE 30 if the oil happens to be at 100C, or SAE 40 if its at 110C.))"
More information please. Is the conclusion only true for the example you cited, or axiomatic?
The thing I really wonder about is whether or not the oil temp spikes as it flows through the journal bearing. Any thoughts, guesses, conjecture......
The oil heats up when it is in the area with the friction and heat....so yea...the bearings cause a localized heating.....that is controlled by flow volume
It also picks up a lot of heat from the cooling of the inside of the rotors and e-shaft
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