Mid Grade gas vs High Octane gas - better performance??

[roccit_53 at scirocco.cs.uoguelph.ca (C Boyko)]

Exactly, but you don't want it running retarded (where's the fun in that?),
so you don't want it to "hear" any knocking. Higher octane than needed to
get to the "no knocking" point is a waste of money and may actually not
burn as readily. Or that's my understanding. Our 16Vs, with pretty high
compression, should be able to take full advantage of high octane fuel,
since they could be expected to knock on the lesser broth. But if you've
got an 8.5:1 8V, they may actually run better on something with a lower
octane rating. My 10:1 8v also gets high octane, and the Cabby with the
stock 8V mill gets the cheapest thing I can find. But the original car in
question was a 16V, which puts it between 10:1 and 11:1 someplace, so it'd
be expected to run better on the good stuff. Which puts us back to the
issue of tuning I guess.
Cathy

PS HOly CRAP is it raining here!!!!!

 On 11:56 pm 03/13/07 "John S. Lagnese" <jlagnese@massed.net> wrote:
> But the knock sensor retards timing to stop the knocking. The sensor
> is like a mike IIRC.
> ----- Original Message -----
> From: "C Boyko" <roccit_53@scirocco.cs.uoguelph.ca>
> To: " John S. Lagnese " <jlagnese@massed.net>
> Cc: <dswalterwi@gmail.com>; <scirocco-l@scirocco.org>
> Sent: Tuesday, March 13, 2007 9:20 PM
> Subject: Re: Mid Grade gas vs High Octane gas - better performance??
>
>
> >  On 8:16 pm 03/13/07 "John S. Lagnese" <jlagnese@massed.net> wrote:
> >>  The higher octane gas performs better. I even get better mileage.
> >>  Its the knock sensor system. Higher octane can be more advanced
> >> timing.
> >  My understanding is that you want to run the lowest octane fuel
> >  that will keep your engine from knocking. The knock sensor will
> >  take over once knock is detected, and pull timing. Having said
> >  that, I always run the highest octane I can get in my 16V. :)
> >  Cathy