California Octane

[TommyW]

lol,I go half 91 and half 100 at the track and all is well.

[norcalpb]

Originally Posted by TommyW

lol,I go half 91 and half 100 at the track and all is well.

I’m gonna try this at my next track day, never thought of it.

Do you put a 93 octane tune on (if tuned) to try and eek out a couple hp?

[tiger1964]

Originally Posted by Ultramaroon

After it learns to pull enough timing, it runs just fine. A little sleepy, but fine.

Thanks. It would be interesting if anyone had done back to back tests, perhaps on a dyne, to see "what was left on the table".

I am pretty sure we can cope with the "loss"; although it would have been great if the car would run well enough, on say, 89 octane which is readily available here. My wife will not be "tracking" the car, it will be a daily driver plus taken on trips where, yeah, we might enjoy picking up the pace on country roads, and it will also be our tow vehicle but I presume the car can cope with that regardless of fuel used.

[RToyo86]

Originally Posted by tiger1964

Thanks. It would be interesting if anyone had done back to back tests, perhaps on a dyne, to see "what was left on the table".

I am pretty sure we can cope with the "loss"; although it would have been great if the car would run well enough, on say, 89 octane which is readily available here. My wife will not be "tracking" the car, it will be a daily driver plus taken on trips where, yeah, we might enjoy picking up the pace on country roads, and it will also be our tow vehicle but I presume the car can cope with that regardless of fuel used.

There has been tests done with 91 vs 93 on gen 1 and there was a whp10hp difference or so. Buried somewhere in the forums.

I wouldn't suggest less than 91.. these engines can get knocky on 91 as it is, less than that the engine won't be happy under heavier loads.

[NoHaveMSG]

Originally Posted by tiger1964

Thanks. It would be interesting if anyone had done back to back tests, perhaps on a dyne, to see "what was left on the table".

I am pretty sure we can cope with the "loss"; although it would have been great if the car would run well enough, on say, 89 octane which is readily available here. My wife will not be "tracking" the car, it will be a daily driver plus taken on trips where, yeah, we might enjoy picking up the pace on country roads, and it will also be our tow vehicle but I presume the car can cope with that regardless of fuel used.

If it is not optimized for the octane you are not really going to gain anything at octane levels above that, and could potentially yeild worse performance, but not likely at 12.5:1 compression.

Since you can't pump your own gas here in Oregon I have had many attendants put 87 in my car. It runs terribly, IAM drops to about .4, so only 40% of requested ignition advance.

[TommyW]

Originally Posted by norcalpb

I’m gonna try this at my next track day, never thought of it.

Do you put a 93 octane tune on (if tuned) to try and eek out a couple hp?

no. I don’t have a 93 tune but thinking of adding a 95. The car runs really nice with the 91/100 combo. 91 can actually be less so everyone should throw a bit of 100 in

[tiger1964]

Originally Posted by RToyo86

There has been tests done with 91 vs 93 on gen 1 and there was a whp10hp difference or so. Buried somewhere in the forums.

Thanks for sparing me the trouble of a Search.

OK, just enough difference to cause angst when refilling. % loss on HP versus % savings per gallon?

[greengs]

Originally Posted by Tcoat

It is the compromise needed to run a high compression NA engine I am afraid.

Mazda3 NA has a higher compression ratio than the BRZ/GR, those only need 87.

[NoHaveMSG]

Originally Posted by greengs

Mazda3 NA has a higher compression ratio than the BRZ/GR, those only need 87.

Pure GDI I am assuming. You can also do things to bleed cylinder pressure like mess with cam timing.

There is also the matter of "can" instead of "should." As I said, I have had 87 put in my car, the ECU does a good job of pulling timing fairly quickly.

[finch1750]

Originally Posted by Sapphireho

Most rich communities in California have stations like this. Here is the pump at the 76 in Saratoga California.

Doesn't even have to be a rich community. We have one in Stockton lol

[OkieSnuffBox]

Originally Posted by RToyo86

There has been tests done with 91 vs 93 on gen 1 and there was a whp10hp difference or so. Buried somewhere in the forums.

I wouldn't suggest less than 91.. these engines can get knocky on 91 as it is, less than that the engine won't be happy under heavier loads.

I'd like to see that because I SERIOUSLY doubt it.

When I had my '13 Mustang GT, it was advertised as 420hp. But in the manual it said 420hp on 93, 414hp on 91.

That's basically statistical noise at that point.

[NoHaveMSG]

Originally Posted by OkieSnuffBox

I'd like to see that because I SERIOUSLY doubt it.

When I had my '13 Mustang GT, it was advertised as 420hp. But in the manual it said 420hp on 93, 414hp on 91.

That's basically statistical noise at that point.

Yeah, tuned for 91 vs. tuned for 93, not going to be 10whp.

Now tuned for 93, but running 91 may cause some issues.

[RToyo86]

Originally Posted by OkieSnuffBox

I'd like to see that because I SERIOUSLY doubt it.

When I had my '13 Mustang GT, it was advertised as 420hp. But in the manual it said 420hp on 93, 414hp on 91.

That's basically statistical noise at that point.

Did a little digging. Link is now dead which doesn't help much for source. 91 vs 93/94 was 6whp, and 10whp on 87 which makes more sense.


https://www.ft86club.com/forums/show...5&postcount=25

[OkieSnuffBox]

Originally Posted by RToyo86

Did a little digging. Link is now dead which doesn't help much for source. 91 vs 93/94 was 6whp, and 10whp on 87 which makes more sense.


https://www.ft86club.com/forums/show...5&postcount=25

Québécois are too busy eating smoked meats to know what's going on.