Fuel octane question

[brtaus]

I just found a place that sells 100 octane fuel. Since AZ does not sell 93 octane, could I use the 100 octane in its place? Why or why not?

[2SSCAMARO]

Originally Posted by brtaus

I just found a place that sells 100 octane fuel. Since AZ does not sell 93 octane, could I use the 100 octane in its place? Why or why not?

if that's 100/104 octane like chevron sells, it's $8.00 per gallon. You must have some real deep pockets!

[v6sonoma]

I would think it would be the same as running 93 in a caviler. You could but why bother. unless you fill it half way with 100 and the next time you hit half you get 91 or even 87 to basically get you to 93ish and just go back and forth as you need gas but that would be more work than I would be willing to do.

[brtaus]

Originally Posted by 2SSCAMARO

if that's 100/104 octane like chevron sells, it's $8.00 per gallon. You must have some real deep pockets!

I didn't see how much it was.

Originally Posted by v6sonoma

I would think it would be the same as running 93 in a caviler. You could but why bother. unless you fill it half way with 100 and the next time you hit half you get 91 or even 87 to basically get you to 93ish and just go back and forth as you need gas but that would be more work than I would be willing to do.

I wonder if its truly 100 octane or if its more like 95 octane due to being watered down or whatever like QT/Circle K 91 octane is more like 89 octane. If that's the case, then wouldn't running the 100 octane with a 93 octane tune be the same.

[Sax1031]

The only reason I would use anything higher than 93 is if I was running boost(supercharger or turbo) or running nitrous on the car. If I was worried about detonation I would run a higher octane gas.

[brtaus]

Originally Posted by Sax1031

The only reason I would use anything higher than 93 is if I was running boost(supercharger or turbo) or running nitrous on the car. If I was worried about detonation I would run a higher octane gas.

I can't run 93 b/c AZ doesn't have 93 thus my original question.

[guyjusthere]

I would say not to, you need to change timing to run such high octane.. 87-93 is a big difference.. 93 to 100 is a HUGE difference...

[Sax1031]

Originally Posted by brtaus

I can't run 93 b/c AZ doesn't have 93 thus my original question.

Ouch not having the ability to get 93 at gas stations would be a big bummer.

[2SSCAMARO]

Originally Posted by brtaus

I can't run 93 b/c AZ doesn't have 93 thus my original question.

You don't absolutely have to have 93 octane. A well tuned engine running 91 octane can easily outperform a not so well tuned one running 93. Buy branded 91 octane only such as BP, Mobile, Sunoco, Chevron, etc. from a high volume sales station. Get a proper tune from a source with proven results and you'll be good to go.

[brtaus]

Originally Posted by 2SSCAMARO

You don't absolutely have to have 93 octane. A well tuned engine running 91 octane can easily outperform a not so well tuned one running 93. Buy branded 91 octane only such as BP, Mobile, Sunoco, Chevron, etc. from a high volume sales station. Get a proper tune from a source with proven results and you'll be good to go.

I have/do exactly as you described. I was just curious about the 100 octane and any benefits it might/might not provide since I can't get 93 octane.

[RedJewel2SS]

i blend 91 octane and 104 octane to make 93. it is an 11:2 ratio.

my car was tuned for 93, but i had to move temporarily and they only sell 91 here. i only use about one tank per month and its only $16 extra per fill up.

[Soundwave]

I would say not to, you need to change timing to run such high octane.. 87-93 is a big difference.. 93 to 100 is a HUGE difference...

You need to change timing to run a higher octane? You have no idea what you're talking about.

We don't have 93 in NM either, only 91. The only reason you would need to run a higher octane is to get less knock. What I did for a while in my old car was fill 3/4 91 octane and the rest 101 (which was 7.15 a gallon here). Google some octane mixing articles and you'll see that doing something like that get you in a 97-98 octane position because of how they mix.

If you just want to run 100 octane (and can afford it) DO IT! Less knock retard (ping for you old timers) the better! This will not make your car faster in a sense unless you are hitting crazy knock (which pulls timing) then you technically will be, but not, get it?

Simple answer to your question is you are fine running 100 octane, just make sure it's unleaded or you'll be replacing O2 sensors in 1000 miles.

[JANNETTYRACING]

Originally Posted by brtaus

I just found a place that sells 100 octane fuel. Since AZ does not sell 93 octane, could I use the 100 octane in its place? Why or why not?

I would suggest you Mix it 50/50 with 87 and it should be just right about 94 octane

If you run the 100 straight without a custom tune for 100 octane 2 things will happen, your fuel mileage will go down and you will lose performance.

Yes too much octane reduces performance.

I can write a custom tune for 100 octane if you want to run it all the time.

Ted.

[Soundwave]

If you run the 100 straight without a custom tune for 100 octane 2 things will happen, your fuel mileage will go down and you will lose performance.

Yes too much octane reduces performance.

I can write a custom tune for 100 octane if you want to run it all the time.

Explain this please, what exactly would you tune?