<VV> timing

[BobHelt at aol.com]

Mike, 
The answer has to be "IT DEPENDS". 
 
This is a rather involved and technical subject so i am just going to hit  
some important determenents. First, for each and every engine speed of any  
engine using a particular fuel there is a spark timing point BTDC that 
develops  maximum torque. This is called the MBT or the maximum best torque  
point.  If the spark occurs before that point or after there is a loss  of 
torque. So for total maximum torque at each and every engine speed, the  timing 
must follow these MBT points. Now if your distributor does follow these  
points, then you already have the max acceleration already available to you. If  
not, then you may get better acceleration at one engine speed and maybe 
worse  accel at another engine speed depending on the MBT curve. You would need 
to know  both the MBT curve and the dist advance curve.
 
Same for fuel mileage, EXCEPT that the vacuum advance takes over at all  
cruise speeds and maximizes gas mileage independent of MBT.
Regards,
Bob Helt.
 
 
 
In a message dated 12/19/2011 5:07:02 P.M. US Mountain Standard Time,  
kovacsmj at sbcglobal.net writes:

Just a  quick one. If an engine timing is set at  factory 10 degrees BTC, 
which  
will give it a bit better acceleration? 8 degrees or 12 degrees. This a  
bit 
generic, but would apply to a Corvair.

Same question about fuel  mileage. Will retarding (8) or advancing (12) 
tend to 
improve gas  mileage?


MIKE  KOVACS