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i filled my sky with gas at Costco the other day and seen pump was labeled
91 octane with 10% ethanol-is this ok for our2.0 turbo kappas ?? or should i pay
28 cents a litre more and stick with no ethanol in gas.will ethanol hurt or am i ok
at 10% ??
 

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On the subject of octane........contrary to popular belief.......

In general for all vehicles, it is best to use the lowest octane that is "safe to use" for your vehicle's engine. In the case with the Redline with direct injection, this is even more of a consideration.

Why? you might ask. The higher the octane, the more carbon build-up that forms on your valves.

What does higher octane do? It slows the burn rate to prevent pre-detonation we all recognize as engine pinging/knocking. The slower burning fuel leaves behind more micro-particles of unburnt fuel that over time develops into soot which then becomes carbon build-up. Many Sky Redline owners know the issue that direct injection has with carbon build-up. The fuel bypasses the outside of the intake valves which otherwise would clean the valve seats as is the case with conventional fuel injection.

Lower octane fuel is more volatile as noted by pre-detonation, so when it is burnt, it leaves less impurities behind on the valves.

Unfortunately changing from high octane fuel used for a long time, to lower octane fuel, often results in instant ping/knock. This is because of the carbon build-up already present. There are de-carbonizing products on the market, one I used with great results was many years ago on a Fiero-GT called D-Karbonizer made by OTC. After the treatment, I was instantly able to use 87 octane for daily commuting.

If you need the performance of higher octane for a particular event, then use it. But for everyday driving, I recommend to use the lowest octane as declared "Safe To Use" for the vehicle.

This is my opinion.
 

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I use 87 octane fuel in my NA and 89 in my RL with no pinging and no loss of power as measured using a G-Tech on full-throttle acceleration tests, so i am definitely in the camp of using the fuel you need and not the "best" available. I do use top-tier (Shell) fuel the majority of the time, and the extra level of detergents it provides is considered to be beneficial.

As far as I know, Costco fuel is top-tier, so there is no reason I know of to avoid using it.
 
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i filled my sky with gas at Costco the other day and seen pump was labeled
91 octane with 10% ethanol-is this ok for our2.0 turbo kappas ?? or should i pay
28 cents a litre more and stick with no ethanol in gas.will ethanol hurt or am i ok
at 10% ??
Other than a few fringe stations around here, there isn't even an option for ethanol free gas. Consider yourself lucky to even have the option. I think the nearest station to me is around 15-20 miles away. I prefer it for the lawn equipment as it obviously sits a while. In the vehicles we have never had an issue using <10% ethanol gas even in the RL and it sometimes goes months between fill ups. Since I don't have easy access to ethanol free gas I usually use Star Tron in my lawn equipment tanks and that seems to help with the ethanol moisture and stabilizes it.

On the subject of octane........contrary to popular belief.......

In general for all vehicles, it is best to use the lowest octane that is "safe to use" for your vehicle's engine. In the case with the Redline with direct injection, this is even more of a consideration.

Why? you might ask. The higher the octane, the more carbon build-up that forms on your valves.

What does higher octane do? It slows the burn rate to prevent pre-detonation we all recognize as engine pinging/knocking. The slower burning fuel leaves behind more micro-particles of unburnt fuel that over time develops into soot which then becomes carbon build-up. Many Sky Redline owners know the issue that direct injection has with carbon build-up. The fuel bypasses the outside of the intake valves which otherwise would clean the valve seats as is the case with conventional fuel injection.

Lower octane fuel is more volatile as noted by pre-detonation, so when it is burnt, it leaves less impurities behind on the valves.
I preach similar to this every time I hear someone say "I only use premium gas in my cars". Sir your F150 does not need premium gas and you are literally wasting money and adding further maintenance to your engine. The gas companies years ago came up with that genius marketing of calling higher octanes "premium" and it's amazing how well it worked. Even modern high compression engines are engineered to run on lower 87 octane. The engine in my Jeep is a 11.3:1 compression ratio which years ago would of been a high compression engine in comparison, but still only uses 87. It's honestly all walks of life I find that have gotten sucked into this myth too. Old, young, wealthy, poor, it doesn't matter. With the easy access of the internet, I'm always surprised on those that still believe this. Coincidentally, they also tend to believe they have to change their oil religiously every 3k miles as well.
 

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Yup - that misimpression about premium equalling more performance has sold a lot of gas at higher prices for the oil companies. And it was especially silly when the cars had fixed ignition - it meant that you could possibly get a bit more power using more ignition advance but most owners either didn't know that nor did they care and they just ran around without changing timing thinking that they had somehow improved power.
 

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OK, so here in Dallas, most stations have a regular which is 87 octane, mid-range which is 89 octane, and premium which is 93 octane.

Which should I be using in my Trifecta-tuned RL? I have been using premium exclusively, but what performance effect will I have if I go "down" to the 89 octane?
 

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If you drop octane rating your knock sensing and ECM controlled retard will get more of a work-out. Will that affect anything? Maybe not, but the idea doesn't feel that good to me. I'd stay with the premium.

Mine was custom tuned for the boost I run with the modified turbo, for our 94 octane gas. When I go to the US where there is often 91 only, I 'soft-foot' it to avoid exercising the advance/retard. Just being cautious.
 

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OK, so here in Dallas, most stations have a regular which is 87 octane, mid-range which is 89 octane, and premium which is 93 octane.

Which should I be using in my Trifecta-tuned RL? I have been using premium exclusively, but what performance effect will I have if I go "down" to the 89 octane?
I contemplated this very thing the other day while at the pump. 89 was a quarter less per gallon than 93. I did the 93 anyway, the tanks not that big I told myself.

When I had ZZP set up my tune I could choose between 91 or 93 octane. Although 93 is plentiful here in TX and the southern US I figured I would like to eventually start going on roadtrips and I know from my work travels that heading north and west often 91 is the highest octane. I had it set for 91 octane, ultimately just because even though all I’ve ever used is 93.
 

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OK, so here in Dallas, most stations have a regular which is 87 octane, mid-range which is 89 octane, and premium which is 93 octane.

Which should I be using in my Trifecta-tuned RL? I have been using premium exclusively, but what performance effect will I have if I go "down" to the 89 octane?
You likely will lose peak performance at lower octane, because the Trifecta tune is designed to push the envelope further than any of the GM tunes.
 
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