Gas mileage and headers

[Guenther, Max [ASCO/PA]]

Does anybody know why oxygenated gas doesn't give you more hp???!
Horsepower is a (rough) linear function of air(oxygen) through the engine.
Its why we do sooooooooooo much better on alky.  

If your using Sunoco 94 I've had problems with that if I left it in the car
for two or three weeks.  Just wouldn't run right until I filled up again.


> Every year during the fall/winter months my car loses about 2-3 mpg. It 
> also happens rather abruptly. All of a sudden my mileage drops. I have
> used 
> Shell Premium 93 octane for the full life of the car so I cannot blame it 
> on any other variables. It is an annual ritual that I do not look forward
> to.
> 
> I read something somewhere once that made some sense of this. I don't 
> remember where but it said something about reformulated winter gasolines 
> that run with a higher oxygen content so that during very cold warm ups
> the 
> engine runs leaner and doesn't pollute as much. Well for those of use that
> 
> have computer controlled cars with oxygen sensors it would seem that the 
> reformulation of the gas is self defeating. With more oxygen content the 
> sensor sees this and richens up the mixture. This of course would mean
> that 
> my car would now use more gas to get what the computer says is the optimum
> 
> mixture.
> 
> I don't know if what I have just said is fact or fantasy but I do know
> from 
> my gas mileage experience and from what I have read that this is about the
> 
> time for these "reformulated" winter grades to be distributed and for my 
> mileage to drop. This could be what has happened to you a purely 
> coincidental time.
> 
> Mike
> 
> 
----------------------------------------------------------------------------
To unsubscribe from gmecm, send "unsubscribe gmecm" (without the quotes)
in the body of a message (not the subject) to majordomo at lists.diy-efi.org