Aftermarket EFI, speed density etc.

[Peter Wales]

Things are getting a little complex here due to the size of the postings, so
lets try and remove some of the flotsam.

>Thankyou for your *amazing* insight.
>
>Let me explain a couple of things.  When I stated *aftermarket efi*, I was.....

ok, you dont want stoichiometric in Australia, its the law in the US and in
England they still sell leaded gas! The question was why use mapping and I
hope it has been answered.

>> >> | MAP and MAF sensors are both useless for much serious performance work.
>> >> | Throttle position is the only reliable method in such cases.
>> >> 
>> >> Why is this?
>> >> 
>For fine tuning (dyno work), it's just as easy to set the engine speed where
>required (assuming you have a decent dyno) and adjust the throttle position
>to give the required manifold pressure (vacuum).  I don't understand how
>Peter finds this any more complicated than setting a throttle position.
>MAP readings are easily reproducable and actually mean something as
>opposed to a voltage output from a throttle positon pot.............


First the threottle position is the correct way, then the MAP sensor.
It seems that Robert is going to be right no matter what the answer is.


>> Lastly, flap air sensors are not notoriously unreliable. If they were there
>> would be ten trillion cars breaking down every minute because of them. They
>> are very reliable in service and if used correctly in race engines they work
>> adequately there as well. 
>
>I disagree here.  Ask any Jaguar mechanic about the reliability of the Lucas
>(Bosch) moving vane MAF meters fitted to XK engined XJ6s........

Lucas and Jaguar!!!! Hardly the definition of reliability. Try asking a BMW
mechanic. And before anyone gets upset over me panning two English
products.... I am English (hangs head in shame)


Peter Wales