Mike:
I think if you look at it a little closer, piston speed is a function
of RPM and the slow burning "flame front" of Nitro starts to get
behind the piston speed as RPM increases so we must add ignition
advance to keep the piston and the flame front in a more or less
ideal positional relationship. So it is both the slow burn rate and
the desire for higher RPM/power that drives the higher advance. Would
still like to know how much advance the F-1 engines use at 20k.
Skip
At 09:56 PM 4/30/2008, Mike Lackey wrote:
>Top Fuel engines need that much timing advance because of the fuel,
>not the rpm. Nitromethane burns much slower than gasoline, so the
>timing needs to be advanced more to maximize power. My street bike
>revs to 14,000 rpm and full advance is only at 43 degrees and it
>uses standard supreme pump gas. I have no idea what F1 uses for
>fuel. Mike ----- Original Message ---- From: Skip Higginbotham
><saltrat@pahrump.com> To: Dave Dahlgren <ddahlgren@snet.net>;
>jgmagoo@comcast.net; land-speed-digest <land-speed@autox.team.net>
>Sent: Wednesday, April 30, 2008 1:26:22 PM Subject: Re: [Land-speed]
>Torque Drop>From>JG Magoo And...how much ignition advance do they
>run at 20k to help the flame front stay up with the piston speed????
>Top Fuel engines run as much as 65 degrees to enable 9000 RPM. It's
>not just VE. Skip At 11:34 AM 4/30/2008, Dave Dahlgren
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