Aquamist HFS-3 and MINI Tank GB

[Buli]

(09-01-2011 11:45 AM)ThumperMCS Wrote:  

(09-01-2011 11:25 AM)Buli Wrote:  I thinking was that the ECU would self tune/adjust to it. I know if I switch from 93 to 91 octane I get knock at idle for a while. I sure wouldn't want to get knock at high rpm from going from the high octane with the meth to low if the meth stopped flowing. That was how I was thinking it might work, and why I will hook the failsafe from the start.

It does to a degree, but this is no where near the same as if you were to get tuned with meth. The amount of timing advance you can run when doing a meth tune is far greater than the self-advance the ECU will do. Also, in regards to AFR's, you have the ability to really lean out the motor when you tuning with meth. Our ECU isn't going to go leaner than the tune your using is telling it to. It will simply lean itself out to try and reach whatever its target lambda might be. So, when using it how we are currently using it, setting up the failsafe is not nearly as critical.

Side note, you should not be getting knock at idle from 2 octane points lower. Out west we only get 91....so I find it hard to believe that it would be knocking under 0 load at idle.

It is not knocking from 91 octane, it is knocking from the change from 93 to 91. It seems to take a tank or more to stop. This has happened all 3 times I couldn't get to the station that has the 93. The knocks happen on a hot day, AC on at idle after I changed from 93 to 91 octane. Maybe that points to a problem with my car.

Good to know about the lower risk with a none meth tune.