Thickest oil you've ever used.
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Nick1994
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10w40 in my Jeep and 5w40 in my previous TDI.
Penrite 20W-60 mineral
Castrol 10W-60 synthetic
And lots of both.
I purchased my first whimpy errr I mean ILSAC oil a few months ago, Castrol Edge 10w30 A5/B5, but I still haven't found the guts to run it. If I do, don't tell my mates down the pub, they will start buying me shandies instead of heavies when it's their shout.
Castrol 10W-60 synthetic
And lots of both.
I purchased my first whimpy errr I mean ILSAC oil a few months ago, Castrol Edge 10w30 A5/B5, but I still haven't found the guts to run it. If I do, don't tell my mates down the pub, they will start buying me shandies instead of heavies when it's their shout.
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Originally Posted By: SR5
Penrite 20W-60 mineral
Castrol 10W-60 synthetic
And lots of both.
I purchased my first whimpy errr I mean ILSAC oil a few months ago, Castrol Edge 10w30 A5/B5, but I still haven't found the guts to run it. If I do, don't tell my mates down the pub, they will start buying me shandies instead of heavies when it's their shout.
Haha we think alike!
10W40 is my "thin" oil
Penrite 20W-60 mineral
Castrol 10W-60 synthetic
And lots of both.
I purchased my first whimpy errr I mean ILSAC oil a few months ago, Castrol Edge 10w30 A5/B5, but I still haven't found the guts to run it. If I do, don't tell my mates down the pub, they will start buying me shandies instead of heavies when it's their shout.
Haha we think alike!
Oh I almost forgot. Back in 1989 my dad bought a brand new 89 Mazda B2200 pickup. That thing received nothing but Pennzoil Conventional 20w50 and a bottle of STP oil treatment.
20W-50 summers in our last old Mercedes gasser, as the OM recommended for warmer weather.
This is the same grade recommended for my old BMW for summer weather, but I've never used that grade in the car.
The W201 OM also gave instructions on appropriate tire pressures for sustained speeds of over 100 MPH, which was about as likely to happen on this side of the Atlantic as was the actual need for a 20W-50.
This is the same grade recommended for my old BMW for summer weather, but I've never used that grade in the car.
The W201 OM also gave instructions on appropriate tire pressures for sustained speeds of over 100 MPH, which was about as likely to happen on this side of the Atlantic as was the actual need for a 20W-50.
0w-40, in my BMW.
Bear in mind that every owner's manual in Oz through the 70s and 80s, and most of the 90s had 20W50 as the grade.
(oh, and as per the new BITOG performance standard - nothing blew up, but from an Oz perspective, nothing used any oil until 200,000+km, and 1 qt/1,000 miles was considered extreme oil usage).
So 20W50
20W50 with a can of STP, or Series 500 gold additive in my hot rodded 6's
Didin't get hooked up in the Penrite +10 thing, but did use a couple of OCIs of STP branded 25W70.
Last time I used anything that thick was on my J Car test 25W70 over winter, diwn to -6 or 7 C...and nothing blew up.
(oh, and as per the new BITOG performance standard - nothing blew up, but from an Oz perspective, nothing used any oil until 200,000+km, and 1 qt/1,000 miles was considered extreme oil usage).
So 20W50
20W50 with a can of STP, or Series 500 gold additive in my hot rodded 6's
Didin't get hooked up in the Penrite +10 thing, but did use a couple of OCIs of STP branded 25W70.
Last time I used anything that thick was on my J Car test 25W70 over winter, diwn to -6 or 7 C...and nothing blew up.
Originally Posted By: Lolvoguy
75w90
86 Nova. Consumed oil so I used this to slow consumption
A gear oil? If so, equal to a 50 weight engine oil. I've used straight 70...we called it helicopter oil, as it was aviation oil.
75w90
86 Nova. Consumed oil so I used this to slow consumption
A gear oil? If so, equal to a 50 weight engine oil. I've used straight 70...we called it helicopter oil, as it was aviation oil.
Heaviest I've used was Nitro 70 in both Kendall back when it was still green and more recently Brad Penn 70. I also have used gear oil in a foolhardy attempt to slow oil consumption in an oil burner, I opted for the 80w140 variety. It was a terrible idea, it stunk SOOOOOOOOOOOOOOOOOOO bad I never did it again, it made the normal oil consumption smell seem like perfume, the only other thing that smelled nearly as bad was Valvoline VR-1 which I also used for an oil change cycle in SAE 60. Nothing really made a difference in consumption still uses on average a quart per 1,000 miles over 3,000 miles to this day.
Eneos 5w50 that I won from a contest on their website. I blended it 2:3 with their 0w20 in my old Maxima.
Also ran Mobil 1 Turbo Diesel Truck 5w40 for years in my TDI before switching to Mobil 1 ESP 5w30.
For the last few years it's been 0w20 in my Fusion, 5w20 in the Freestyle.
Also ran Mobil 1 Turbo Diesel Truck 5w40 for years in my TDI before switching to Mobil 1 ESP 5w30.
For the last few years it's been 0w20 in my Fusion, 5w20 in the Freestyle.
Do we have to confine it specifically to engine lubricating oil?
I'm currently using SAE 60 in the dashpots of the SU carburetors on my MG. There's a lot of arguments about the correct oil for these, with many folks suggesting 3-in-1, Marvel Mystery Oil, ATF, or official SU SAE 20 for use. At the other end of the spectrum, 20W-50 or EP90 gear oil are often suggested. The purpose of any kind of oil is to temporarily increase the vacuum through the carb throat during acceleration resulting in a richer mixture-it's the same idea as an accelerator pump, although doesn't go so far as to actually squirt gas into the throat like a pump. In any case, heavier oil keeps the mixture richer for longer and makes the acceleration a bit more "punchy."
Otherwise, I go through a rather large amount of 20W-50 in this car. It's used in both the engine and transmission, although the transmission rarely needs attention.
I'm currently using SAE 60 in the dashpots of the SU carburetors on my MG. There's a lot of arguments about the correct oil for these, with many folks suggesting 3-in-1, Marvel Mystery Oil, ATF, or official SU SAE 20 for use. At the other end of the spectrum, 20W-50 or EP90 gear oil are often suggested. The purpose of any kind of oil is to temporarily increase the vacuum through the carb throat during acceleration resulting in a richer mixture-it's the same idea as an accelerator pump, although doesn't go so far as to actually squirt gas into the throat like a pump. In any case, heavier oil keeps the mixture richer for longer and makes the acceleration a bit more "punchy."
Otherwise, I go through a rather large amount of 20W-50 in this car. It's used in both the engine and transmission, although the transmission rarely needs attention.
10W-40 Valvoline conventional
Originally Posted By: bunnspecial
Do we have to confine it specifically to engine lubricating oil?
I'm currently using SAE 60 in the dashpots of the SU carburetors on my MG. There's a lot of arguments about the correct oil for these, with many folks suggesting 3-in-1, Marvel Mystery Oil, ATF, or official SU SAE 20 for use. At the other end of the spectrum, 20W-50 or EP90 gear oil are often suggested. The purpose of any kind of oil is to temporarily increase the vacuum through the carb throat during acceleration resulting in a richer mixture-it's the same idea as an accelerator pump, although doesn't go so far as to actually squirt gas into the throat like a pump. In any case, heavier oil keeps the mixture richer for longer and makes the acceleration a bit more "punchy."
Nice that you've worked that one out too.
I had triples on a few of my Holden 6 cylinders, and the advice back in the day was to run them dry and let them "breathe"...I settled 20w50 after doing my own tests, and thicker always made them punchier in transition.
edit...in non engine oils, thickest I've used is Omala 1500
https://www.mil-specproducts.com/Documents/802_PDS-OMALA OIL 1500.pdf
Do we have to confine it specifically to engine lubricating oil?
I'm currently using SAE 60 in the dashpots of the SU carburetors on my MG. There's a lot of arguments about the correct oil for these, with many folks suggesting 3-in-1, Marvel Mystery Oil, ATF, or official SU SAE 20 for use. At the other end of the spectrum, 20W-50 or EP90 gear oil are often suggested. The purpose of any kind of oil is to temporarily increase the vacuum through the carb throat during acceleration resulting in a richer mixture-it's the same idea as an accelerator pump, although doesn't go so far as to actually squirt gas into the throat like a pump. In any case, heavier oil keeps the mixture richer for longer and makes the acceleration a bit more "punchy."
Nice that you've worked that one out too.
I had triples on a few of my Holden 6 cylinders, and the advice back in the day was to run them dry and let them "breathe"...I settled 20w50 after doing my own tests, and thicker always made them punchier in transition.
edit...in non engine oils, thickest I've used is Omala 1500
https://www.mil-specproducts.com/Documents/802_PDS-OMALA OIL 1500.pdf
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Originally Posted By: Shannow
Originally Posted By: bunnspecial
Do we have to confine it specifically to engine lubricating oil?
I'm currently using SAE 60 in the dashpots of the SU carburetors on my MG. There's a lot of arguments about the correct oil for these, with many folks suggesting 3-in-1, Marvel Mystery Oil, ATF, or official SU SAE 20 for use. At the other end of the spectrum, 20W-50 or EP90 gear oil are often suggested. The purpose of any kind of oil is to temporarily increase the vacuum through the carb throat during acceleration resulting in a richer mixture-it's the same idea as an accelerator pump, although doesn't go so far as to actually squirt gas into the throat like a pump. In any case, heavier oil keeps the mixture richer for longer and makes the acceleration a bit more "punchy."
Nice that you've worked that one out too.
I had triples on a few of my Holden 6 cylinders, and the advice back in the day was to run them dry and let them "breathe"...I settled 20w50 after doing my own tests, and thicker always made them punchier in transition.
edit...in non engine oils, thickest I've used is Omala 1500
https://www.mil-specproducts.com/Documents/802_PDS-OMALA OIL 1500.pdf
I know that variable venturi, constant depression carbs are the norm-or at least very common-in the UK and Australia while the fixed venturi, variable depression type carbs are not so common in the US. For the most part, we only see them on British sports cars since the home market volume models weren't exported here in large numbers. That's in contrast to vehicles like the MGB, where roughly 90% of the ~500,000 made came over here. Triumphs for NA started using Z-S carbs sometime in the '60s I think, while the MGB got a single Z-S in '75 or so. As I'm sure you know, both work basically the same but the Z-S is somewhat more complicated. The US market Z-Ss also have an EPA-mandated automatic choke which is known to be problematic if not maintained. In either case, though, a lot of mechanics back in the day pushed Weber conversions because they work like the Carter/Rochester/Holley etc that American mechanics were use to.
In any case, the best MG mechanic in the US and probably one of the top in the world is John Twist of University Motors in Michigan. He does "rolling tech sessions" at a lot of shows, although he often just sets the the timing and the carbs(it's hard to do more than that when you have 20 cars in line).
When I went to one tech session, he asked the owner of every car what type of oil was in their carburetors. He let me pass when I said 20W-50, but folks running light oil(again, 3-in-1, ATF, Marvel Mystery Oil, or any other light oil) got a shot of EP-90 or maybe 80W-90 in their carbs. As mentioned earlier, this is comparable in viscosity to 20W-50. I would use 20W-50 in a pinch since I always have some in the car, although they need topping up so infrequently that I've never had a need for an emergency fill.
That converted me to using heavier oil, and I've found that every increase in viscosity I've made has resulted in "punchier" acceleration. It's still not like a Weber with an accelerator pump, but overall I prefer the performance of the SU.
I've hear of folks running no oil. For the sake of experimenting, I've removed the the cap from the dampers which has the same effect as running no oil. It makes little difference at constant speed, but the acceleration is definitely "sluggish" and the car will cough and sputter if it's pushed too hard. Granted a stronger spring would make some difference, but there's a limit to that. Putting the dampers back in with any weight oil is like doing a tune-up.
Originally Posted By: bunnspecial
Do we have to confine it specifically to engine lubricating oil?
I'm currently using SAE 60 in the dashpots of the SU carburetors on my MG. There's a lot of arguments about the correct oil for these, with many folks suggesting 3-in-1, Marvel Mystery Oil, ATF, or official SU SAE 20 for use. At the other end of the spectrum, 20W-50 or EP90 gear oil are often suggested. The purpose of any kind of oil is to temporarily increase the vacuum through the carb throat during acceleration resulting in a richer mixture-it's the same idea as an accelerator pump, although doesn't go so far as to actually squirt gas into the throat like a pump. In any case, heavier oil keeps the mixture richer for longer and makes the acceleration a bit more "punchy."
Nice that you've worked that one out too.
I had triples on a few of my Holden 6 cylinders, and the advice back in the day was to run them dry and let them "breathe"...I settled 20w50 after doing my own tests, and thicker always made them punchier in transition.
edit...in non engine oils, thickest I've used is Omala 1500
https://www.mil-specproducts.com/Documents/802_PDS-OMALA OIL 1500.pdf
I know that variable venturi, constant depression carbs are the norm-or at least very common-in the UK and Australia while the fixed venturi, variable depression type carbs are not so common in the US. For the most part, we only see them on British sports cars since the home market volume models weren't exported here in large numbers. That's in contrast to vehicles like the MGB, where roughly 90% of the ~500,000 made came over here. Triumphs for NA started using Z-S carbs sometime in the '60s I think, while the MGB got a single Z-S in '75 or so. As I'm sure you know, both work basically the same but the Z-S is somewhat more complicated. The US market Z-Ss also have an EPA-mandated automatic choke which is known to be problematic if not maintained. In either case, though, a lot of mechanics back in the day pushed Weber conversions because they work like the Carter/Rochester/Holley etc that American mechanics were use to.
In any case, the best MG mechanic in the US and probably one of the top in the world is John Twist of University Motors in Michigan. He does "rolling tech sessions" at a lot of shows, although he often just sets the the timing and the carbs(it's hard to do more than that when you have 20 cars in line).
When I went to one tech session, he asked the owner of every car what type of oil was in their carburetors. He let me pass when I said 20W-50, but folks running light oil(again, 3-in-1, ATF, Marvel Mystery Oil, or any other light oil) got a shot of EP-90 or maybe 80W-90 in their carbs. As mentioned earlier, this is comparable in viscosity to 20W-50. I would use 20W-50 in a pinch since I always have some in the car, although they need topping up so infrequently that I've never had a need for an emergency fill.
That converted me to using heavier oil, and I've found that every increase in viscosity I've made has resulted in "punchier" acceleration. It's still not like a Weber with an accelerator pump, but overall I prefer the performance of the SU.
I've hear of folks running no oil. For the sake of experimenting, I've removed the the cap from the dampers which has the same effect as running no oil. It makes little difference at constant speed, but the acceleration is definitely "sluggish" and the car will cough and sputter if it's pushed too hard. Granted a stronger spring would make some difference, but there's a limit to that. Putting the dampers back in with any weight oil is like doing a tune-up.
Standard manifolds with an SU might have a ''hot spot'', but multiple carbs hardly ever. So they are pretty cold blooded and take time to warm up - push the choke in and they spit back and die. Thicker oil helps when cold, but I usually used ATF in dashpots. I can imagine US mechanics being baffled by them - as an apprentice I was taught by a guy well versed in them, and even Kiwi mechanics who didn't work on BMC's couldn't centre a main jet. When the floating needle came out there was no need, but I was still rebuilding SU's well into the '90's. My favorite carburettor.
Emissions killed the SU, put them on a digital 4 or 5 gas and you'll see how high the HC and CO are, that needle jet doesn't atomise the fuel enough. Last of them had stepper motors on the main jet controlled by the ECU. Such a good idea, but still too dirty.
Emissions killed the SU, put them on a digital 4 or 5 gas and you'll see how high the HC and CO are, that needle jet doesn't atomise the fuel enough. Last of them had stepper motors on the main jet controlled by the ECU. Such a good idea, but still too dirty.
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Changed the oil/filter in a Chrysler 300m I had. I Double gasket the filter like an idiot. Lost 4 quarts in about 10 seconds on startup. Topped it off with 15w40 rotella (in December/ January in Ohio).
Couldn't tell a difference. No knock or anything. Thickest I've used in a non Diesel engine.
Couldn't tell a difference. No knock or anything. Thickest I've used in a non Diesel engine.
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