What Octane for the FR-S?

[Muaddib]

94 Chevron but at a cost of over $6 per gallon.

[TM]

Originally Posted by SkullWorks

Not sure what you think you might be inferring...E85 is commonly understood to be 109 octane

Usually 91 octane no ethanol. I try to get 93 whenever i can (tolled interstates or when i go down to nj or nyc)

[l0aded]

Just wondering but do you guys still get the chirp with 93 octane+ gas? Or is it an ethanol content thing?

- poor 91 octane guy

[wheelhaus]

Originally Posted by topazsparrow

94 Chevron. Smells so good

I've read avoiding gas with ethanol will help avoid the chirps. I'm at 1500km and chirp free so far.

It's not a direct correlation. Avoiding E10 helped some, not others.

E85 should not be used in place of gasoline or E10 unless the car is specifically designed for "flex fuel" or has been tuned for E85. It's stoichiometric ratio is different and needs to run richer. Simply dumping it into a car that's not designed to use it will cause it to run lean.

The whole octane thing is pretty well covered as to "why" we need high octane for the FA20 engine. Those at low altitude should stick with 93 (RON+MON/2) minimum, higher altitude can use 91 with no danger due to lower atmospheric pressure. In short, the high octane simply makes it more stable and resistant to preignition (a.k.a. ping, detonation, knock, etc). This, in turn, allows the ECU to advance timing as far as it's programming allows, and allows tuners and builders to be more aggressive.

[roddy]

Originally Posted by l0aded

Just wondering but do you guys still get the chirp with 93 octane+ gas? Or is it an ethanol content thing?

- poor 91 octane guy

For me, yes. Others have said differently, but in my particular case, The 94 octane is an E10 blend and chirps like crazy. In my area, Shell's premium (91 Octane) has no Ethanol and I get no chirps when using it. As much as I HATE the crickets, I usually run the 94 in the summer as the car feels better when using it. In the colder months it doesn't seem to make much difference.

[roddy]

Originally Posted by Brahsbrah

Wish we had something other than 91 Octane here in Nova Scotia.

Did you ever have Sunoco stations in NS? Here in Ontario, all of the Sunoco stations were re-branded as Petro Canada or Husky a couple of years ago. Most of the ones that had 94 and were changed to PC kept the 94.

[BlackMagicSir]

100 Octane where I'm from. On a related note, does anybody know the pros/cons between a 100 Octane fuel and an E85? I googled it but there wasn't a helpful result in the first page.

[Brahsbrah]

Originally Posted by roddy

Did you ever have Sunoco stations in NS? Here in Ontario, all of the Sunoco stations were re-branded as Petro Canada or Husky a couple of years ago. Most of the ones that had 94 and were changed to PC kept the 94.

Haven't noticed it, although I usually get gas at Esso. I'll have to keep an eye outfor Petros and have a look.

I need those 3x Esso points though on Supreme

[reeves]

Originally Posted by SkullWorks

Not sure what you think you might be inferring...E85 is commonly understood to be 109 octane

Nothing to infer.. the pump is labeled 104 here.

[Splat]

Originally Posted by Muaddib

94 Chevron but at a cost of over $6 per gallon.

Holly Cow

[SkullWorks]

Originally Posted by reeves

Nothing to infer.. the pump is labeled 104 here.

That is interesting.

[Steve201brz]

Since day 1 I've been using 93 and never had any problems n it runs great. One time on a long drive I made a pit stop for gas and a drink, it was a long drive n my buddy was going to fill up n I forgot to tell him 93... So I got a tank of 87 and I definitely felt a difference on the those last 200 miles. Might be a decent difference in octane but now I definitely get 93 or higher if I can find it. I feel guilty giving it lower lol

[PStaff716]

93 octane from Sunoco..it's just so damn close to my house. Anyone know if that's an inferior company to purchase gas from? Never really thought too hard about it..

[topazsparrow]

Originally Posted by Muaddib

94 Chevron but at a cost of over $6 per gallon.

Same, It's about 1.53 / L right now for me.