Alloytec octane requirements

[Boost]

What octane gasoline are you guys running in your Alloytec engines? I have an '07 CTS stock that I have been using premium fuel in, and after careful research I think I will start filling it with 87 octane, since that's what the manual says. It is the 3.6 liter. I thought there may be a reliability and performance benefit due to extreme IATs here, but it's getting rather poor economy so if it doesn't knock on regular, I will stick with that. Very little chance that the specified lower octane will actually burn better, right? One hears rumors that on "some cars", regular gas runs better. That is certainly not been my experience with various other models though... thanks for the input, I hope I can start using a good brand of 87 in this sucker!

[joecar]

Use compression ratio as a guide.

[Boost]

Ok, it's 10.2:1. (?)

[GMPX]

I will say that on my car (3.0L LFW) it struggles on our local 91 Octane (which is rated different to the US, I think it's about the same as your 87). We have 91, 95 & 98 Octane at the pump.
On 91 there is audible knock!! Mind you, Holden have about 6 degrees more timing in their tables vs the same engine in the US
No difference in fuel economy between them all.

[joecar]

Compressio ratio 10:1 or greater is considered high compression, and rule of thumb is to use Super (92-93 in US 49 states).

98 Aust. equates to about 92-93 US.

[Boost]

So could it be like the the new 1.4t Ecotec where they say it runs on 87 but it runs like crap unless you use 93? 87 is recommended, should I even try it? The tiny bit of saving would be welcome but not it it pings and drives piss poor. Maybe I'll try it a little and let you guys know. How about 89? :( Initially from reading up on it I thought this thing might actually run "better" on regular, lol

[joecar]

Try it, and monitor for knock.

[Boost]

I will! Can I scan and log it even though there is should I no support? It's an '07 CTS 3.6. Or should I use the Tech2? Thanks!

[joecar]

No pid...?

Then listen very carefully for knock, maybe even using knock phones.

[Boost]

I was under the impression that my '07 Caddy CTS 3.6 was not supported / tuneable with EFILive, but hoping it could be scanned?? Can you set me straight on this?
What controller?