Improving Mileage Re: <VV> Weber DCOE questions

[FrankCB at aol.com]

Pat,
    If you're looking to improve the gas mileage of a street driven Corvair 
turbo engine, the best way is to convert the stock pressure retard on the 
distributor to provide vacuum advance.  When I did this on my 180 that was being 
driven daily to work and back, my mileage went up from 18 mpg to 22 mpg and I 
wasn't driving to get good mileage, but with a heavy foot to get to work on 
time.(:-)
    Details on how to do this are explained in the Turbocharging chapter of 
the Corvair Basics Manual.  The stock 180 engine has a FIXED timing advance up 
to 4000 rpm OR until boost is achieved, so obviously it can't achieve anywhere 
it's mileage potential.  Just remember, you still need to keep some method of 
providing timing retard under boost pressure.
    As a side benefit, you'll find that vacuum advance gives improved part 
throttle acceleration as well as improved mileage and is an ideal combination 
for street driving just as it is in normally aspirated (non-turbocharged) 
Corvairs.
    Or you could always ask the winner of the Economy Run at the last 
Convention in Lexington, KY.  His TURBO Corvair got over 40 mpg.!!!!!
    Frank "stock is a good beginning" Burkhard  

In a message dated 4/25/05 8:57:57 AM Eastern Daylight Time, 
PVanderl at mwestmp.com writes:
Anyone out there have any experience with a Weber DCOE setup for a turbo? I
have one that starts easy, idles smooth, and runs great with ample boost My
only question at this point is the mileage. Mine is around 15 at best with
most of my driving is on the highway. My diffy is a 3:55 coupled to a 65 4
speed. Is this close to what it should be or am I way off? I checked it last
week so I avoided getting into boost as often as I usually do. Except for a
little black smoke when I'm pushing that manifold pressure gauge to the +,
it is set pretty well. 


Pat Vanderlind
65 Corsa 180 cpe DCOE40 with the progressive secondary modification.
62 Monza 900 cvt 102 PG