Thought I would share my research regarding pump fuel with the fuel question asked today. Carried these tests out with some core engineering testing principles in mind to ensure accuracy. Some hardcore content below, won't take too long to read.
I did some through in-car fuel performance testing in Vancouver and Calgary last summer, with a cammed 3.2 Jetta with a very optimized 94 tune and data logging observing knock, timing, mass air flow and most importantly calculated Torque channel which directly reflects what the ECU thinks the fuel is capable of, very useful for comparing if one fuel makes more than the other and you calculate power from torque. With some background info, my car makes over 280hp at sea level in Vancouver with Chevron 94, 275hp with shell 91, consistently at many gas stations, with 102RON in Germany the car made just shy of 285, so yes our 94 in best case scenario does still leave 5hp to be desired, but you won't notice it. No other 94 fuels are available in Vancouver and it was pointless to test other 91 since I could easily hear pinging if I used it. I was however interested to try 91 in Calgary as technically at higher elevation it is less likely prone to knock due to lower density causing less combustion energy and lower speed of sound.
How I tested was on the same night, must be no rain and not super hot outside. Let's say I have just 5L or so of Chev 94 left, I would make 3 pulls from 2-7200RPM in 3rd gear logging the data with 1min between runs taking not of initial IAT. Then I will top off my tank with a different fuel and drive around for 20km to let the ECU calibrate to the new fuel then repeat the same test at the same IAT on the stretch of road immediately on the same night. This minimizes variables and produce a fair comparison. What I'm looking for is difference in performance not just peak numbers, cuz the numbers will change with the same fuel on a different say. Repeating this comparison on different days using each fuel being switched out as the benchmark for the new fuel is how I can accurately come to conclusion to what is better for full throttle performance on a mildly tuned NA car. And elevation is a huge factor as well, just 1100m up from sea level my cammed NA car lost roughly 11%, stock NA cars are affected a little less, turbo cars lose about the same until boost comes on but that's a whole different topic, my car can also barely make it up the hill at 60km/h in third gear at Pike's peak 4000m. Again who different topic but I thought I'd mention it.
If fuelling for your 94 tune in Calgary, the best to worst is Chevron 94 BC/AB and PC 94 within 1hp of each other ~250, Husky 94 was tested against PC94 and produced 3hp less (244 vs 247), Husky 94 produced 6hp more than Shell 91 (246 vs 240), and PC 91 vs Shell 91 was both about 238. So basically don't consider 91 fuels if you are running 93 tune. The 93 tune does adjust for worse gas but the adjustment is more for protection than trying to run best on 91 on its own, if you want to know more can read on how knock sensor works with ECU. And TBH with the turbo cars you're already making 30% more power from stock with a 91 tune, to me it's kinda pointless to get an extra 2% hp for the few times that 2% makes a difference and have to find 94 which costs more. Of course this is my opinion for street used turbo cars, my opinion is different for track day cars or NA cars.
To be more anal in the future I could integrate the area under the power curve to asses which fuel has the most usable power between certain RPM ranges. But from visual, the higher peak power fuels also had higher torque overall, makes sense.
As a Motorsport engineer, it doesn't matter how big a tuning company is, when they just place the blame on fuel and claim we have crappier fuel compared to the US or EU it doesn't work with me, because we don't live there and elevation is a much bigger influence as you will read why. Most of them want you to believe your car can achieve so much more so they car sell a product although you would rarely have that option available. If that 10hp is worth it to you then sure, but most cases you could save money and hassle with a slightly more conservative tune and fuel.
I did some through in-car fuel performance testing in Vancouver and Calgary last summer, with a cammed 3.2 Jetta with a very optimized 94 tune and data logging observing knock, timing, mass air flow and most importantly calculated Torque channel which directly reflects what the ECU thinks the fuel is capable of, very useful for comparing if one fuel makes more than the other and you calculate power from torque. With some background info, my car makes over 280hp at sea level in Vancouver with Chevron 94, 275hp with shell 91, consistently at many gas stations, with 102RON in Germany the car made just shy of 285, so yes our 94 in best case scenario does still leave 5hp to be desired, but you won't notice it. No other 94 fuels are available in Vancouver and it was pointless to test other 91 since I could easily hear pinging if I used it. I was however interested to try 91 in Calgary as technically at higher elevation it is less likely prone to knock due to lower density causing less combustion energy and lower speed of sound.
How I tested was on the same night, must be no rain and not super hot outside. Let's say I have just 5L or so of Chev 94 left, I would make 3 pulls from 2-7200RPM in 3rd gear logging the data with 1min between runs taking not of initial IAT. Then I will top off my tank with a different fuel and drive around for 20km to let the ECU calibrate to the new fuel then repeat the same test at the same IAT on the stretch of road immediately on the same night. This minimizes variables and produce a fair comparison. What I'm looking for is difference in performance not just peak numbers, cuz the numbers will change with the same fuel on a different say. Repeating this comparison on different days using each fuel being switched out as the benchmark for the new fuel is how I can accurately come to conclusion to what is better for full throttle performance on a mildly tuned NA car. And elevation is a huge factor as well, just 1100m up from sea level my cammed NA car lost roughly 11%, stock NA cars are affected a little less, turbo cars lose about the same until boost comes on but that's a whole different topic, my car can also barely make it up the hill at 60km/h in third gear at Pike's peak 4000m. Again who different topic but I thought I'd mention it.
If fuelling for your 94 tune in Calgary, the best to worst is Chevron 94 BC/AB and PC 94 within 1hp of each other ~250, Husky 94 was tested against PC94 and produced 3hp less (244 vs 247), Husky 94 produced 6hp more than Shell 91 (246 vs 240), and PC 91 vs Shell 91 was both about 238. So basically don't consider 91 fuels if you are running 93 tune. The 93 tune does adjust for worse gas but the adjustment is more for protection than trying to run best on 91 on its own, if you want to know more can read on how knock sensor works with ECU. And TBH with the turbo cars you're already making 30% more power from stock with a 91 tune, to me it's kinda pointless to get an extra 2% hp for the few times that 2% makes a difference and have to find 94 which costs more. Of course this is my opinion for street used turbo cars, my opinion is different for track day cars or NA cars.
To be more anal in the future I could integrate the area under the power curve to asses which fuel has the most usable power between certain RPM ranges. But from visual, the higher peak power fuels also had higher torque overall, makes sense.
As a Motorsport engineer, it doesn't matter how big a tuning company is, when they just place the blame on fuel and claim we have crappier fuel compared to the US or EU it doesn't work with me, because we don't live there and elevation is a much bigger influence as you will read why. Most of them want you to believe your car can achieve so much more so they car sell a product although you would rarely have that option available. If that 10hp is worth it to you then sure, but most cases you could save money and hassle with a slightly more conservative tune and fuel.
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