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Regular VS Premium - let’s put an end to an ongoing debate?
- Thread starter airdzi
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It's a thing that some can do. Apply sound learning and experience to make objectives possible. Some even get paid to do it.
I don’t disagree with you... I own an LS430 that must lose 20hp on regular. But that was a high performance V8 (for the day) for a slick luxury car.
However this is a 5.7 liter truck engine that just loafs around. It will be just fine on regular. We aren’t talking about a brand new M5 here.
Over-towing well beyond specs is not sound anything. Are you kidding me?!
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Ethanol is just a cheap way to boost octane ratings ... Ethanol‘s octane rating is 114 ... basiclly deluging gasoline with rating 84 adding 10% ethanol gives you a minimum of 87 octane rating .
Adding 15% gives you a 88 octane and so on ... basiclly higher rating more ethanol is crap .
NASCAR has jumped on the ethanol band wagon , the ethanol they use is not the same as you buy at the pump , its Sunoco green E15 is suppose to be 98 octane but has been tested as high as 104 octane , not the same as the crap you buy at the pump .
Gasoline business is a slimy industry , I stick with cheapest name brand like costco and add my own fuel lubricant .
If you can buy 100% gasoline is allways the best .
Adding 15% gives you a 88 octane and so on ... basiclly higher rating more ethanol is crap .
NASCAR has jumped on the ethanol band wagon , the ethanol they use is not the same as you buy at the pump , its Sunoco green E15 is suppose to be 98 octane but has been tested as high as 104 octane , not the same as the crap you buy at the pump .
Gasoline business is a slimy industry , I stick with cheapest name brand like costco and add my own fuel lubricant .
If you can buy 100% gasoline is allways the best .
Why are you adding fuel lubricant to a Top Tier Costco gasoline? Gasoline needs to meet federal regulations so it’s really not all that different.
bloc
SILVER Star
Plus our engines aren’t direct injected where the need to lubricate a high pressure pump is important.
@MrX, let me save you some effort, I’ve been down this road a few times before. Teckis is a good guy posting lots of good stuff to this forum but will repeatedly remind us of his tuning & engineering experience and all but state that means they know exactly what toyota/lexus did in this case, because that is what he would have done. To date no one has posted actual evidence of a different calibration between LX and LC. The manual requiring premium is being presented as that evidence, which is tenuous at best and could easily have been impacted by marketing departments. Plus, 2hp is well under the legal “fudge factor” limits allowed when marketing an engine’s performance specs.
If someone would post the spark tables from a HPTuned LC and LX we could settle this, but it hasn’t been done and isn’t worth the cost in HPT credits to me. To address one thing.. the blank ecu part number is the same, but it must then be coded per VIN and technically there is room for the programming to be different based on whether it’s a cruiser or LX.
I posted on the first page of this thread, @airdzi breakdown of how our engines seem to learn what kind of fuel we are running through feedback from the knock sensors over time is the closest thing we have to ACTUAL EVIDENCE that we might benefit from running premium fuel. That is a far cry from the blanket statement that a LX must run premium but it doesn’t matter in a cruiser.
Personally I’ve settled on the belief that the calibrations are the exact same, and if the owner wants to get a few more hp and torque they can spend the money on premium per @airdzi evidence of a feedback system. But this also means no harm will come to a LX running RUG because the same protections against knock getting bad enough to cause damage as a LC are built in. Toyota is famous for being conservative in everything they do, and this includes tuning. Meaning RUG is even less likely to cause problems than with some other cars on the market.
I’m careful to note this as a belief though, based on the evidence I’ve seen. I don’t possess some kind of grand insider knowledge.
@MrX, let me save you some effort, I’ve been down this road a few times before. Teckis is a good guy posting lots of good stuff to this forum but will repeatedly remind us of his tuning & engineering experience and all but state that means they know exactly what toyota/lexus did in this case, because that is what he would have done. To date no one has posted actual evidence of a different calibration between LX and LC. The manual requiring premium is being presented as that evidence, which is tenuous at best and could easily have been impacted by marketing departments. Plus, 2hp is well under the legal “fudge factor” limits allowed when marketing an engine’s performance specs.
If someone would post the spark tables from a HPTuned LC and LX we could settle this, but it hasn’t been done and isn’t worth the cost in HPT credits to me. To address one thing.. the blank ecu part number is the same, but it must then be coded per VIN and technically there is room for the programming to be different based on whether it’s a cruiser or LX.
I posted on the first page of this thread, @airdzi breakdown of how our engines seem to learn what kind of fuel we are running through feedback from the knock sensors over time is the closest thing we have to ACTUAL EVIDENCE that we might benefit from running premium fuel. That is a far cry from the blanket statement that a LX must run premium but it doesn’t matter in a cruiser.
Personally I’ve settled on the belief that the calibrations are the exact same, and if the owner wants to get a few more hp and torque they can spend the money on premium per @airdzi evidence of a feedback system. But this also means no harm will come to a LX running RUG because the same protections against knock getting bad enough to cause damage as a LC are built in. Toyota is famous for being conservative in everything they do, and this includes tuning. Meaning RUG is even less likely to cause problems than with some other cars on the market.
I’m careful to note this as a belief though, based on the evidence I’ve seen. I don’t possess some kind of grand insider knowledge.
I feel injectors lubrication important ... I have seen Tacomas go 300k and just put cheapest gas they could find . I see no benefit to running high octane unless your supercharged .
I feel the 200 land cruiser has plenty of power running the cheap stuff with Lucas Upper cylinder may be snake oil but never had any problems running it and its cheap .
The other big gas scam is ... We are switch to “ summer blend “ will cost more money ... Huge scam with ethanol the same blended gas , even the areas that have blended gas year round believe there is different gas ... LOL
I have never thought ... Hey I need more power lets put the 93 octane in today .. LOL
I usually grab the diesel truck , I would love to have a diesel 200 ... no need for 8 different grades of gas these days .
I feel the 200 land cruiser has plenty of power running the cheap stuff with Lucas Upper cylinder may be snake oil but never had any problems running it and its cheap .
The other big gas scam is ... We are switch to “ summer blend “ will cost more money ... Huge scam with ethanol the same blended gas , even the areas that have blended gas year round believe there is different gas ... LOL
I have never thought ... Hey I need more power lets put the 93 octane in today .. LOL
I usually grab the diesel truck , I would love to have a diesel 200 ... no need for 8 different grades of gas these days .
I use chevron fuel system cleaner every 10-15k miles. Why? I have no reason other than i like Chevron gasoline (heard once that their fuel additives were good)…and I just like to waste money. 
And yes i run ethanolized-regular gas for my LC…usually from Exxon, Chevron, or Shell.
And yes i run ethanolized-regular gas for my LC…usually from Exxon, Chevron, or Shell.
I bet all 3 of those stations sell fuel from the same blending terminal. It only becomes branded gas when they literally squirt the respective manufacturers detergent into the tank upon delivery. And even then, addictive packages are only made by 1 or 2 companies.I use chevron fuel system cleaner every 10-15k miles. Why? I have no reason other than i like Chevron gasoline (heard once that their fuel additives were good)…and I just like to waste money.
And yes i run ethanolized-regular gas for my LC…usually from Exxon, Chevron, or Shell.
There is an "old school" service station about .5 miles from my house. They sell non-ethanol 87 and 92. They still have the old pumps that don't take credit cards and are open from 7-6, so I don't always remember to use them to get gas. I filled up my LX this morning with the 92 because they only charge about 8% more for it, and last time I was there, the owner said they swapped their big tank from 87 to 92 because everyone was buying the 92 these days, so ideally higher turnover. From reading this thread, I guess I have to remember to fill up a few tanks to see if I'll notice a difference in power/mileage. Lately, I've been running whatever is available and 87 octane (been using gas stations in rural AR on road trips to state parks), so should be going from a worst case to best case scenario.
Folks use premium gas on their LCs? lol
1world1love
SILVER Star
I like to visit this thread on occasion to see if it did, in fact, put an end to the debate. Seeing as how there are few constants in life, it is somewhat comforting that the status quo remains.
For my part, I feel like what is important is to be consistent with the grade you use. I also am partial to Chevron but will also use Mobil or Shell or even Costco.
One of the reasons why I choose those options, and what I actually think is the most critical thing in choosing a fuel, is to use the stations with the highest volume, because at the end of the day, month old premium is probably not as good as day old regular.
I have no data to support any of this.
For my part, I feel like what is important is to be consistent with the grade you use. I also am partial to Chevron but will also use Mobil or Shell or even Costco.
One of the reasons why I choose those options, and what I actually think is the most critical thing in choosing a fuel, is to use the stations with the highest volume, because at the end of the day, month old premium is probably not as good as day old regular.
I have no data to support any of this.
bloc
SILVER Star
This. Not to mention water, likelihood of incorrect deliveries getting diluted with correct fuel, pump filters changed, etc.
It’s not nickel and diming, it’s being smart and not falling for Lexus BS marketing, or wasting unnecessary money. Why should I spend $67 filling my truck up (for 300 miles of range) when I could spend $50? That adds up quite a bit over time. Regular fuel is fine in any 5.7 truck.
Hypothetically, assume for just a second that the opposite were true. You know from your LS430, another vehicle that uses the "required" verbiage, that there is an effect with using lower grade fuel. The concern isn't really about power. It's about knock events that the car's ECU is responding to. Less power is the secondary consequence to low grade knock, that over the long term can impact an engine. Or use it at the wrong time with heavy loads, hot weather, bad gas, and long term microscopic pitting and carbon build up due to uncontrolled flame fronts with low grade knock...is there margin left?
Is it wasting money? Is it marketing BS? Maybe @Kilcarnup has a point?
The LC guys don't have a horse in this conversation. The LC is calibrated for 87. When I owned an '06 LX470, it was 91 "recommended" and I used that to my advantage. It tells you the ECU tune is setup safely for 87 and can take advantage of 91. I put 87 in it all day, with 91 for heavy towing work. Yet calibrations like this don't use timing tables that fully maximize higher octane because they have to walk a finer line against knock thresholds.
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The power plant in the LS430 was exclusive to that car and that car alone. It’s not an appropriate comparison.
And this is where the divide is. Amazes me that decades after carbs and distributors, to think that it is all hardware driven.
It's not.
If you car is modern has sensors and an ECU that's not from the dark ages of EFI.. it will adjust on the fly based on fuel quality and other factors to provide more efficiency/power/etc.
Is it negligible in most of our cases? for sure.. but to each their own.
I can bash out a 10km jog regardless what I put into my body.. but I know I feel better doing it after eating clean.
You do you, I'll do me and we'll all be happy.
Is it negligible in most of our cases? for sure.. but to each their own.
I can bash out a 10km jog regardless what I put into my body.. but I know I feel better doing it after eating clean.
You do you, I'll do me and we'll all be happy.
I think Bully dog makes tuners for the 5.7. They might know more about the toyota ecu fuel and spark tables in relation to octane.
