Ancient History

[tom cloud]

   [ snip ]

>> So, how does one take a 400+ CID engine and get that kind of mileage
>> unless he's running a 1.7:1 rear end (i.e. L-O-W r's) -- even if he had
>> 100% VE ?
>> 
>> Tom
>
>Tom,
>	who cares about CFM, it varies too much too worry about.  As well as
>your air fuel ratio is determined by mass not CFM.
>	You only run 100%VE at close to or wide open throttle, unless you're
>turbo'd.  At very light throttle conditions, your VE is determined by
>pressure AND rpm's.  Sure, your VE still follows your torque curve, but
>your mass flow into the engine is very minimal at high vacuum
>situations.
>	For example, running down the road at 100%VE, or WOT, you might be
>running 8 to 10 ms injector timing, where as at light throttle
>conditions, you might see 1.5 to 2 ms.  Same RPM, different pressure,
>thus less fuel.
>	Sure it's the same CFM inside the manifold, but prior to the throttle
>body (at atmospheric pressure) the CFM is much lower.
>
>Todd Knighton
>Protomotive Engineering
>

So, you're telling me these mpg figures don't bother you?

Tom