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I live in California we on have 91 octane I was wondering if it's safe to use a fuel additive like an octane booster. Can somebody shed some light on this.
 

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Why would you want to use octane boost? Since you have 91 octane fuel, your car is already operating at top efficency, and adding octane will not increase power or performance without an aftermarket tune that supports higher octane fuel. Octane is not a measure of power in a fuel, but rather a measure of resistance to detonation.

I use a bottle of Techron fuel system cleaner every 5,000 miles and prefer Top Tier has stations.
 

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Why would you want to use octane boost? Since you have 91 octane fuel, your car is already operating at top efficency, and adding octane will not increase power or performance without an aftermarket tune that supports higher octane fuel. Octane is not a measure of power in a fuel, but rather a measure of resistance to detonation.

I use a bottle of Techron fuel system cleaner every 5,000 miles and prefer Top Tier has stations.
I have to disagree. I have 92 pump fuel in Washington. With an E-18 mix, in my 2.0L engine, my 0-60, 1/8 mile and 1/4 mile numbers dropped. They also dropped even more with a race fuel mix of 94.6 octane. I just ran a 4.17 0-60 and a 8.01 1/8 mile two nights ago. I also am running the 1/4 in the 12.5s and with the E-85 mix had a hero run in the 12.4s.

Now, full disclosure, I AM running a piggyback tune, but on straight 92, I’m getting 4.7s, 8.3s and 12.8s with the tune.

You may say there is no benefit of fuel over 91, but you’re just a guy in the internet like me, and do not tune or build these engines in Italy. If you look on the threads here, you see major performancedifferences between those running 91 and 93 pump gas.

Until Alfa tells us what octane these engines are designed for, we will never know. Stating they “recommend” 91 doesn’t mean that’s the limit. It’s the suggested minimum.
 

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I have to disagree. I have 92 pump fuel in Washington. With an E-18 mix, in my 2.0L engine, my 0-60, 1/8 mile and 1/4 mile numbers dropped. They also dropped even more with a race fuel mix of 94.6 octane. I just ran a 4.17 0-60 and a 8.01 1/8 mile two nights ago. I also am running the 1/4 in the 12.5s and with the E-85 mix had a hero run in the 12.4s. Now, full disclosure, I AM running a piggyback tune, but on straight 92, I’m getting 4.7s, 8.3s and 12.8s with the tune. You may say there is no benefit of fuel over 91, but you’re just a guy in the internet like me, and do not tune or build these engines in Italy. If you look on the threads here, you see major performancedifferences between those running 91 and 93 pump gas. Until Alfa tells us what octane these engines are designed for, we will never know. Stating they “recommend” 91 doesn’t mean that’s the limit. It’s the suggested minimum.
Further disclaimer: He has the fastest 2.0 on the planet - good job. That's faster than most stock QVs can get on street tires.

I also run Boostane in my Quadrifoglio, for times when I need the speed. I ran a 3.74 0-60 on a prepped surface with Boostane and Hoosier DR2s on a ~50-degree track.
I have since started adding 2 gallons of E85 to my tank when speed runs are in the forecast. I also have the Madness MPP, which adjusts for higher octane & increases boost when it finds said octane.

Next weekend I'm headed to the track with 3 gallons of E85, 64 ounces of Boostane Pro, and the same Hoosier DR2 tires. I expect to surpass the 3.74 mark. We'll see!
 

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“...full disclosure, I AM running a piggyback tune, but...”

At this point, everything else you say is pointless as you are not running a stock 2.0. Apples and Oranges and all, you cannot infer anything from your data.
 

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“...full disclosure, I AM running a piggyback tune, but...”

At this point, everything else you say is pointless as you are not running a stock 2.0. Apples and Oranges and all, you cannot infer anything from your data.

This is true but bottom line is we just need to log knock retard on 91 vs 93.

Theres none on the 2.0l on 93 octane which is why i have the highest trap speed on 93 octane and have the fastest 40-100mph time of any stock turbo giulia. Ive run ms109 and e30 and gotten no better. Theres no way i would since no timng could be added with no retard happening.

Now if i was running California 91 crap its possible i would be retarding timing and benefit from increased octane.

91 folks need to log
 

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“...full disclosure, I AM running a piggyback tune, but...”

At this point, everything else you say is pointless as you are not running a stock 2.0. Apples and Oranges and all, you cannot infer anything from your data.
Not true at all. It is not “pointless” what’s pointless is you saying 91 octane is the maximum octane the engine can take advantage of since the manual RECOMMENDS it. NO WHERE does it say it’s the highest it can adjust for.

Also a piggy back tune doesn’t change the ECU like a flash tune, which why I specified that it was a piggyback. The piggyback only tells the system to use more boost.

FYI, results speak louder than some made up limits due to ones poor reading comprehension.
 

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I think the argument over octane comes down to one simple answer. A tuned or piggyback car will benefit from higher octane. A stock one won’t. The compression will not change on a stock engine. Now you might not see much after 93/94 on a piggyback but on a tune with a little sauce on it you can pull some timing. My fastest times are on 100 octane. 260gt. When I add boostane or octanium I only see minor gains since it’s not oxygenated and loaded with MMT. I do see some gains from octane boosters but I feel the ECU starts to compensate on that sooner than it does the pure 100. For me 100 octane works well.
 

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Not true at all. It is not “pointless” what’s pointless is you saying 91 octane is the maximum octane the engine can take advantage of since the manual RECOMMENDS it. NO WHERE does it say it’s the highest it can adjust for.

Also a piggy back tune doesn’t change the ECU like a flash tune, which why I specified that it was a piggyback. The piggyback only tells the system to use more boost.

FYI, results speak louder than some made up limits due to ones poor reading comprehension.
im not shitting in your Wheaties by no means. I think you have great runs and success with what you are doing. I do wonder what that piggyback is doing long term. It could be running very lean. Not saying it is but my first thought when I seen how much faster it is than the common piggybacks is what’s happening with fuel trims. I’m not saying I’m right. Just my first instinct. Maybe the TMC has figured out how to maximize the multi-air. Just keep an eye out.
 

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I think the argument over octane comes down to one simple answer. A tuned or piggyback car will benefit from higher octane. A stock one won’t. The compression will not change on a stock engine. Now you might not see much after 93/94 on a piggyback but on a tune with a little sauce on it you can pull some timing. My fastest times are on 100 octane. 260gt. When I add boostane or octanium I only see minor gains since it’s not oxygenated and loaded with MMT. I do see some gains from octane boosters but I feel the ECU starts to compensate on that sooner than it does the pure 100. For me 100 octane works well.
You're tuned. Different ballgame altogether. Even stock QV and 2.0l calibration style may be done by different calibrators too and far different. Who knows. The only way to know is to log.

If you log ecu and you're pulling timing. You can benefit.
 

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im not shitting in your Wheaties by no means. I think you have great runs and success with what you are doing. I do wonder what that piggyback is doing long term. It could be running very lean. Not saying it is but my first thought when I seen how much faster it is than the common piggybacks is what’s happening with fuel trims. I’m not saying I’m right. Just my first instinct. Maybe the TMC has figured out how to maximize the multi-air. Just keep an eye out.
Its not any faster than other piggy backs. Its quicker because of awd but not faster in trap or 40-100. We're all about the same 310 to 330hp or so trapping 104 to 107mph depending on weather.
 

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Its not any faster than other piggy backs. Its quicker because of awd but not faster in trap or 40-100. We're all about the same 310 to 330hp or so trapping 104 to 107mph depending on weather.
Yes. Quicker and faster are two different things. I’m just saying his 0-60 and 1/8 times are a few tenths faster than what we have seen. I think his car is benefiting from the fuel in some capacity. Maybe a little timing. Maybe he is always with wind to back. Idk Yes he is awd. But I think he is almost .3 faster to 60 than the other awd running madness. It’s possible he has a one off car that makes 15-20 more hp. Maybe he got a press car lol.
 

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im not shitting in your Wheaties by no means. I think you have great runs and success with what you are doing. I do wonder what that piggyback is doing long term. It could be running very lean. Not saying it is but my first thought when I seen how much faster it is than the common piggybacks is what’s happening with fuel trims. I’m not saying I’m right. Just my first instinct. Maybe the TMC has figured out how to maximize the multi-air. Just keep an eye out.
I appreciate it. I run it pretty tame most of the time. I only juice it up and run it hard every now and then weather permitting.
 

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Its not any faster than other piggy backs. Its quicker because of awd but not faster in trap or 40-100. We're all about the same 310 to 330hp or so trapping 104 to 107mph depending on weather.
The AWD is also extra weight, so that is a detriment in the 1/4 mile and a net positive for the 0-60. Also that sunroof isn’t helping either. 😉👍
 

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You're tuned. Different ballgame altogether. Even stock QV and 2.0l calibration style may be done by different calibrators too and far different. Who knows. The only way to know is to log.

If you log ecu and you're pulling timing. You can benefit.
Tuned is 100% different ballgame. I will have some good logs and data by end of month. Will have videos of the journey she’s going through. I’m probably going to find out the limits of the QV and hopefully she makes it. New turbos. Dyno tuned WMI. I’m also going to top speed run at Johnny bohmer. I’m guessing 204mph. We shall see.
 

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Its not any faster than other piggy backs. Its quicker because of awd but not faster in trap or 40-100. We're all about the same 310 to 330hp or so trapping 104 to 107mph depending on weather.
I think it’s safe to say, we’re all in agreement that the “91 octane is the maximum effective octane gas” argument is asinine.
 

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Tuned is 100% different ballgame. I will have some good logs and data by end of month. Will have videos of the journey she’s going through. I’m probably going to find out the limits of the QV and hopefully she makes it. New turbos. Dyno tuned WMI. I’m also going to top speed run at Johnny bohmer. I’m guessing 204mph. We shall see.
Damn looking forward to it and to see those wmi numbers! 👍
 

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Damn looking forward to it and to see those wmi numbers! 👍
im excited. Counting the days lol. I’m hoping to be around 630-640 whp. But who knows. Turbos should add 40 whp each. WMI should add maybe 25-35 whp. But more important will lower IATs. It’s gonna be a tire fire for sure. I’m already spinning with less power. Hope all goes well. After this I’m done with it.
107880
 

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Yes. Quicker and faster are two different things. I’m just saying his 0-60 and 1/8 times are a few tenths faster than what we have seen. I think his car is benefiting from the fuel in some capacity. Maybe a little timing. Maybe he is always with wind to back. Idk Yes he is awd. But I think he is almost .3 faster to 60 than the other awd running madness. It’s possible he has a one off car that makes 15-20 more hp. Maybe he got a press car lol.
He's not making 15 to 20 more hp than everyone. Hes making 15-20 more than some and 5hp less than others Trap speeds are hp. 60-130 is hp. Gains in trap speed from the 1/8 to the 1/4 is hp as thats how fast the car is accelerating in the back half.

0-60 is launch. Et is traction. He pulled a 1.76 60 foot. Thats better than anyone by far. Thats incredible

His trap is 106mph. He picks up 20mph from the 1/8 mile to the 1/4 mile going from 86mph to 106mph.

That's great but nothing our cars dont do on pump gas.

There are cars running faster 40-100mph and picking up more speed in the back half. Not by any significant amount but the point is his car is quicker to 40mph because of traction not hp. Thats why you see the great et

Now that said maybe his car is retarding on 91. Hed have to log to know. I just know on 93 i get zero retard even in 95 degree weather doing back to back 150mph runs. 91 octane maybe i would. But logging is the only way to know
 
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