Help with Oil choices for off road racing
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Originally Posted By: Bajabum85
Thank you everyone for there input! Really impressed with this forum! I am leaning pretty strong to a 15w50-20w50 in either Mobil 1 or Amsoil. What would determine the need of 15w vs. 20w?
I would look at the actual 40/100 degree viscosities. In theory, only the "cold" viscosity should change 15W50 vs 20W50, but there is a lot of room for variance within each SAE grade. Depending on your oil operating temp, you would want to go thicker or thinner. Both Amsoil or Mobil in those weights would be good choices. Maybe go with whatever is most cost effective and readily available (probably the Mobil).
Thank you everyone for there input! Really impressed with this forum! I am leaning pretty strong to a 15w50-20w50 in either Mobil 1 or Amsoil. What would determine the need of 15w vs. 20w?
I would look at the actual 40/100 degree viscosities. In theory, only the "cold" viscosity should change 15W50 vs 20W50, but there is a lot of room for variance within each SAE grade. Depending on your oil operating temp, you would want to go thicker or thinner. Both Amsoil or Mobil in those weights would be good choices. Maybe go with whatever is most cost effective and readily available (probably the Mobil).
Originally Posted By: Bajabum85
What would determine the need of 15w vs. 20w?
Starting in cold(er) temps.
Originally Posted By: Bajabum85
I have some pretty decent discounts available to me with a racing program on AMSOIL
Mobil 1 15w-50 is $5/quart at Walmart ($25/5qt. jug). Can you get Amsoil that cheap?
What would determine the need of 15w vs. 20w?
Starting in cold(er) temps.
Originally Posted By: Bajabum85
I have some pretty decent discounts available to me with a racing program on AMSOIL
Mobil 1 15w-50 is $5/quart at Walmart ($25/5qt. jug). Can you get Amsoil that cheap?
Originally Posted By: Bajabum85
Thank you everyone for there input! Really impressed with this forum! I am leaning pretty strong to a 15w50-20w50 in either Mobil 1 or Amsoil. What would determine the need of 15w vs. 20w?
Bigger viscosity spreads are better in racing because the VII's actually thicken the oil more when super hot. Most people think VII's only work on the cold side, but they really keep the oil thick on the hot side more. Thats why M1 0w40, or M1 Racing 0w-50 are popular choices in racing. So a full-syn 5w-40 with euro specs, or an M1 5w-50 is great for you too.
http://www.mobil.com/english-US/Passenger-Vehicle-Lube/pds/NAXXMobil-1-FS-X2-5W50
You really can't go wrong using any xw-50 Mobil 1 product, but I still think M1 0w-40 is best here.
Thank you everyone for there input! Really impressed with this forum! I am leaning pretty strong to a 15w50-20w50 in either Mobil 1 or Amsoil. What would determine the need of 15w vs. 20w?
Bigger viscosity spreads are better in racing because the VII's actually thicken the oil more when super hot. Most people think VII's only work on the cold side, but they really keep the oil thick on the hot side more. Thats why M1 0w40, or M1 Racing 0w-50 are popular choices in racing. So a full-syn 5w-40 with euro specs, or an M1 5w-50 is great for you too.
http://www.mobil.com/english-US/Passenger-Vehicle-Lube/pds/NAXXMobil-1-FS-X2-5W50
You really can't go wrong using any xw-50 Mobil 1 product, but I still think M1 0w-40 is best here.
Also check out Total Quartz Racing 15W 50. I've used this in several applications that had no reason to live but did...oil temps way north of 300°F and sustained 6000+ rpms, and it's cheap through SSF
Originally Posted By: 1JZ_E46
The Pennzoil Baja truck uses off the shelf Pennzoil platinum euro 5W-40. Driven racing oil is also very proven in NASCAR.
One would think any 229.5 euro-spec 0w-40 or 5w-40 (HTHS=3.5-3.7) would be fine for this application.
IF you go to an Xw-50 (HTHS=4.0+) then you lose horsepower to the more thicker oil. Also fuel economy.
In racing, if winning is important, then you want the thinnest possible oil that survives the race. Any euro-spec Xw-40.
If just doing it for pure fun, don't care if you win, definitely go for the thicker Xw-50 for better protection. M1 15w-50 or M1 Racing 0w-50 suggested.
The Pennzoil Baja truck uses off the shelf Pennzoil platinum euro 5W-40. Driven racing oil is also very proven in NASCAR.
One would think any 229.5 euro-spec 0w-40 or 5w-40 (HTHS=3.5-3.7) would be fine for this application.
IF you go to an Xw-50 (HTHS=4.0+) then you lose horsepower to the more thicker oil. Also fuel economy.
In racing, if winning is important, then you want the thinnest possible oil that survives the race. Any euro-spec Xw-40.
If just doing it for pure fun, don't care if you win, definitely go for the thicker Xw-50 for better protection. M1 15w-50 or M1 Racing 0w-50 suggested.
Originally Posted By: oil_film_movies
Bigger viscosity spreads are better in racing because the VII's actually thicken the oil more when super hot. Most people think VII's only work on the cold side, but they really keep the oil thick on the hot side more. Thats why M1 0w40, or M1 Racing 0w-50 are popular choices in racing.
Disagree vehemently...M1 only claim a 3.8 HTHS for their 0W50 racing oil.
HTHS is what protects bearings (and is 150C, which is racing bearing territory), and 3.8 for a "50" is woefull.
Bigger viscosity spreads are better in racing because the VII's actually thicken the oil more when super hot. Most people think VII's only work on the cold side, but they really keep the oil thick on the hot side more. Thats why M1 0w40, or M1 Racing 0w-50 are popular choices in racing.
Disagree vehemently...M1 only claim a 3.8 HTHS for their 0W50 racing oil.
HTHS is what protects bearings (and is 150C, which is racing bearing territory), and 3.8 for a "50" is woefull.
Originally Posted By: Shannow
Disagree vehemently...M1 only claim a 3.8 HTHS for their 0W50 racing oil. HTHS is what protects bearings (and is 150C, which is racing bearing territory), and 3.8 for a "50" is woefull.
HTHS isn't the whole story. You get 300C (not just 150C HTHS) in the rings in race vehicles.
Remember that 3.8 HTHS in M1 0w50 isn't trying to be a huge number, for racers who want more horsepower to the ground to actually win.
There was a Formula 1 article that corroborates Mobil's 0w50 high VI approach saying it's important that an oil doesn't thin out too much in the really hot spots.
I'll side with F1 and Mobil engineers on this one. They aren't amateurs.
Racing: Winning, or just joy-riding.
Winning means you want just enough HTHS, not more for no valid reason.
Joy-riding means some extra HTHS is probably a good idea to be more certain the engine lasts several races.
Disagree vehemently...M1 only claim a 3.8 HTHS for their 0W50 racing oil. HTHS is what protects bearings (and is 150C, which is racing bearing territory), and 3.8 for a "50" is woefull.
HTHS isn't the whole story. You get 300C (not just 150C HTHS) in the rings in race vehicles.
Remember that 3.8 HTHS in M1 0w50 isn't trying to be a huge number, for racers who want more horsepower to the ground to actually win.
There was a Formula 1 article that corroborates Mobil's 0w50 high VI approach saying it's important that an oil doesn't thin out too much in the really hot spots.
I'll side with F1 and Mobil engineers on this one. They aren't amateurs.
Racing: Winning, or just joy-riding.
Winning means you want just enough HTHS, not more for no valid reason.
Joy-riding means some extra HTHS is probably a good idea to be more certain the engine lasts several races.
Yes, the rings DO get that hot...in the reversal zone, it's boundary and mixed, which is additive, not viscosity dependent.
In the remainder, it's High Shear as well.
If you are trying to minimise power wastage, then why do they give an oil which has a (poor) 40 grade high shear viscosity the KV of a 50, and waste energy pumping it around the place ?
Of course you don't want it thinning as it gets hotter, you don't want it thickening as it gets colder...
Is that F1 article the one that one poor sap took as actually thickening as it got hotter and made a fool of himslef spouting that misinterpretation ?
IIRC, that one didn't even mention High Shear viscometry, and was pretty basic...please link it if it's a different one, and goes into making a low HTHS/High KV oil and the benefits in doing so.
In the remainder, it's High Shear as well.
If you are trying to minimise power wastage, then why do they give an oil which has a (poor) 40 grade high shear viscosity the KV of a 50, and waste energy pumping it around the place ?
Of course you don't want it thinning as it gets hotter, you don't want it thickening as it gets colder...
Is that F1 article the one that one poor sap took as actually thickening as it got hotter and made a fool of himslef spouting that misinterpretation ?
IIRC, that one didn't even mention High Shear viscometry, and was pretty basic...please link it if it's a different one, and goes into making a low HTHS/High KV oil and the benefits in doing so.
Originally Posted By: Shannow
Yes, the rings DO get that hot...in the reversal zone, it's boundary and mixed, which is additive, not viscosity dependent.
Getting higher viscosity on those hot rings means less boundary/mixed.
And, the less boundary/mixed you have, the less wear and friction.
That's what Mobil and racers are doing.
Yes, the rings DO get that hot...in the reversal zone, it's boundary and mixed, which is additive, not viscosity dependent.
Getting higher viscosity on those hot rings means less boundary/mixed.
And, the less boundary/mixed you have, the less wear and friction.
That's what Mobil and racers are doing.
Originally Posted By: oil_film_movies
Originally Posted By: Shannow
Yes, the rings DO get that hot...in the reversal zone, it's boundary and mixed, which is additive, not viscosity dependent.
Getting higher viscosity on those hot rings means less boundary/mixed.
And, the less boundary/mixed you have, the less wear and friction.
That's what Mobil and racers are doing.
Actually, it's pretty hard to avoid boundary/mixed in the ring reversal area, as the velocity passes through zero (there goes hydrodynaimc).
You've fallen into the common trap about wear and friction.
In boundary/mixed, the co-efficient of friction is typically lower with the presence of FMs, while the wear is a little higher...as the oil film gets thicker, wear goes down, but friction goes up.
The mind trap is pretty common when people talk ILSAC...less friction doesn't mean less wear.
I'd be most surprised if F1 engineers were increasing viscosity top protect the top rings, as that would be around a horsepower wasted for nothing....they don't race 200,000 miles (usually).
Originally Posted By: Shannow
Yes, the rings DO get that hot...in the reversal zone, it's boundary and mixed, which is additive, not viscosity dependent.
Getting higher viscosity on those hot rings means less boundary/mixed.
And, the less boundary/mixed you have, the less wear and friction.
That's what Mobil and racers are doing.
Actually, it's pretty hard to avoid boundary/mixed in the ring reversal area, as the velocity passes through zero (there goes hydrodynaimc).
You've fallen into the common trap about wear and friction.
In boundary/mixed, the co-efficient of friction is typically lower with the presence of FMs, while the wear is a little higher...as the oil film gets thicker, wear goes down, but friction goes up.
The mind trap is pretty common when people talk ILSAC...less friction doesn't mean less wear.
I'd be most surprised if F1 engineers were increasing viscosity top protect the top rings, as that would be around a horsepower wasted for nothing....they don't race 200,000 miles (usually).
Originally Posted By: oil_film_movies
Originally Posted By: Shannow
Disagree vehemently...M1 only claim a 3.8 HTHS for their 0W50 racing oil. HTHS is what protects bearings (and is 150C, which is racing bearing territory), and 3.8 for a "50" is woefull.
HTHS isn't the whole story. You get 300C (not just 150C HTHS) in the rings in race vehicles.
Remember that 3.8 HTHS in M1 0w50 isn't trying to be a huge number, for racers who want more horsepower to the ground to actually win.
There was a Formula 1 article that corroborates Mobil's 0w50 high VI approach saying it's important that an oil doesn't thin out too much in the really hot spots.
I'll side with F1 and Mobil engineers on this one. They aren't amateurs.
Racing: Winning, or just joy-riding.
Winning means you want just enough HTHS, not more for no valid reason.
Joy-riding means some extra HTHS is probably a good idea to be more certain the engine lasts several races.
They must have some pretty wonderful VII's that don't turn to sludge in the top ring groove and cause sticking.
Originally Posted By: Shannow
Disagree vehemently...M1 only claim a 3.8 HTHS for their 0W50 racing oil. HTHS is what protects bearings (and is 150C, which is racing bearing territory), and 3.8 for a "50" is woefull.
HTHS isn't the whole story. You get 300C (not just 150C HTHS) in the rings in race vehicles.
Remember that 3.8 HTHS in M1 0w50 isn't trying to be a huge number, for racers who want more horsepower to the ground to actually win.
There was a Formula 1 article that corroborates Mobil's 0w50 high VI approach saying it's important that an oil doesn't thin out too much in the really hot spots.
I'll side with F1 and Mobil engineers on this one. They aren't amateurs.
Racing: Winning, or just joy-riding.
Winning means you want just enough HTHS, not more for no valid reason.
Joy-riding means some extra HTHS is probably a good idea to be more certain the engine lasts several races.
They must have some pretty wonderful VII's that don't turn to sludge in the top ring groove and cause sticking.
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