Ignition advance, was Re: alternative engines, WARPED

[Greg Hermann]

>At 12:47 PM 5/18/99 -0400, you wrote:
>>Just use manifold vacuum.  Carb vacuum is ported so there is no vacuum at
>>idle.  This can help or hurt the idle quality.  Try it and see.
>>
>>Gary Derian <gderian at oh.verio.com>
>>
>	
>
>	You sure about that?  I have always understood that a vac advance can
>reads ported vacuum in order to affect a curve that begins as the throttle
>is opened and increases as more throttle is applied, up to the point at
>which all vacuum (manifold and therefore ported as well) fades under heavy
>throttle openings, at which point the advance will decline again and the
>engine will see only mechanical advance.  This is apparently to provide
>extra advance for economy at part throttle.  Anybody who can further
>illustrate this concept, please do because if I am wrong here I'm going to
>have some serious rethinking to do!

Sorry Aaron--

Ported vacuum was first used to provide LESS advance at idle so as to
decrease idle emissions! (But to still keep more like the ideal advance at
cruise.)

Regards, Greg
>
>
>	Aaron Willis
>	ICQ #27386985
>	AOL IM: hemiyota
>	http://surf.to/garage-te51 Garage TE51 International