Alright, bear with me on this... So with level 3, it requires 91 octane... what would be the result if you were to run level 3 on 90 octane, or even 89, with the timing retarded a bit?

Would you still see some performance improvements or should I just run it at level 2 with lower octane fuel?

Any thoughts are appreciated.

Thanks!

 

Yes, I think you will still see gains over level 2, just not as much as you would with higher octane and bumped timing.

 

*bump* anyone else?

 

I would research this Verryyyyyyyyyyyyyyyyyy carefully. You don't want detonation or any undue stresses on valves or pistons.

 

Hi.

My take on this...

The timing function - that's a global spark adder, right? Adds / removes advance irrespective of rpm or load?

If that's the case, then 'sysman_rick' is probably right. There are operating parameters where the engine can tolerate either more or less timing depending upon the load, temperature, and a host of other variables.

Soooo... if a tune is by default set for a recommended octane minimum ( 91), reducing timing may not completely address the continuously variable min octane requirements of the engine during operation.

Further, if you incurred some detonation during said operation, the knock sensing system will just pull out more timing anyway, which will hurt performance even more.

Bottom line - the control you have is far from granular enough.

I'd stick to the recommendation.

Make any sense?

IMHO only, folks.... okay?

Cheers
Bubba

 

Thanks for the advice guys. That's kind of what I was thinking, but I'm no expert so I thought I'd throw it out there.

The reason I was wondering is that I'm about to take a trip and won't need huge performance, but the shifting characteristics of the level 3 would be nice. I'd rather not pay for premium fuel, though... lol

 

Have you ever compared your gas mileage running 2 with that of 3?
I get about 11% better on 3 and that more than pays for the extra cost of premium.

 

With my normal driving conditions, I didn't really notice much difference. I'm usually 50/50 city/hwy. When I get more hwy, I see a bigger difference (up to 18/19 AMPG.