[Bosch, AN, Andrew, Dr]

Hi! I'm not sure that this is going to be of much help, but in case 
it is I'm replying to you re your question about fuel enrichment. As 
far as I'm aware, something like 8:1 is way too rich. I would suggest 
that you connect up a rich/lean indicator, and then set up your 
injection system to run rich, around 12:1. Then drive the car, either 
on the road if your measuring equipment permits, or on a dyno. You 
will then be able to grdually lean out the mixture until you get max 
power, listening for detonation all the time as you do so. Running 15 
psi boost, on an intercooled, 8:1 CR motor and using 93 octane 
(R+M/2) octane fuel should give peak power at an AFR  of about 13:1 
or just under. Adjustment of this ratio based on air temp would be 
useful, as otherwise you could run too lean as the air temp drops.

Hope this helps. Let me know how you go if you have the time.

Andrew

 










Dr A. N. Bosch
Physiology Department/ Sports Science Institute
University of Cape Town Medical School
P. O. Box 115
Newlands 7700
South Africa