Date: Wed, 23 Jun 2004 08:20:06 -0400 From: "Fred W." <Fred.Willsnospampam myrealbox.com> Subject: Re: BMW or Saab Convertible
"Dave Hinz" <DaveHinznospamcop.net> wrote in message news:2jtafvF15gla2U1nospamberlin.de... > On Wed, 23 Jun 2004 06:36:24 -0400, Fred W. <Fred.Willsnospampam> wrote: > > > > While the lierature says "unleaded premium", remember that these cars are > > made to run all around the world. US Mid grade (89 AKI) is fine for most > > BMWs. The ECU's will retard the timing just like on the SAABs. The only > > difference is the SAAB will also limit boost if it detects pinging, so your > > loss of power when using lower octane fuel is greater in the SAAB. > > The ECU that Saab has used for quite a while now, will back off spark > timing, or boost, or both, depending on a number of factors. It's all > mapped to find the optimal output given the current predetonation > situation. > > It'd be interesting to see torque curves for several engines, with > different grades of gas, to see just how good they do. The only torque > curves I've ever seen (for anything) don't show a comparison of that sort, > but I'd love to see it. Anyone with a Dyno want to do a bit of > experimenting? > You're right Dave. The curves you see are always done under totally optimum conditions. It would be cool to see some "real world" comparisons of what happens under lesser conditions. -Fred W
 |
 |
 |
 |
 |
