Steve,

I am sorry, but the Zemco doesn't seem to be available in Phoenix any 
longer.  However, I see that there is a post with Zemco ordering info this 
morning, as well as another recommendation.

My last Zemco installation was in 1988, on a Mazda.  I could get you that 
model number, but I don't think it would be useful.  Over the years that I 
installed them, Zemco made only one model, so there wasn't any choice. 
 What I did see was a gradual improvement in the design.  The first one had 
a wheel pickup and had a separate computer box.  The last one worked either 
from a wheel pickup, or ignition, and had the electronics integrated into 
the servo housing.  There were other smaller packaging changes over the 
years as well.  However, the functionality and flawless performance 
remained the same from my 1st 1970's installation to my latest.

I think that the vacuum leak is a non-problem.  The leak is too small to 
affect the mixture.  However, I think that it would probably negate the 
effectiveness of any small vacuum reservoir.  However, the issue is 
probably moot since I have observed the unit's ability to hold full 
throttle as you pointed out.

If you end up with one, would you please pass along the source and current 
price?  I think my '88 price was $60.

Thanks,
Mike

Michael A. Radtke  -  Z74               Voice: 602-862-4897
Bull                                      FAX:         4853
13430 N. Black Canyon Hwy.
Phoenix, AZ  85029                      Email: m.radtke@bull.com