So what is the best way to set up for single plug ignition, using the Bosch CDI in my basically stock US market '77? I say basically stock, because the car has SC cams, and maybe a 1.0 wastegate spring. (I see 1.0 on the boost gauge, so I am guessing that the prior owner put in a spring.) My aims are to improve low end throttle response (the Turbo bugaboo, I guess) and fuel mileage.

I've spent a little time studying the factory manual, and I see that the '77 came with a vacuum retard and nearly 30 crankshaft degrees of mechanical advance. It seems that the vacuum retard is there to "light off" the thermal reactors, which have been replaced by "bypass pipes." My first guess is that I'd be better off with the '76 distributor, with it's 20 crankshaft degrees of crankshaft advance plus vacuum advance. But, probably I could do better than this, too. Does anyone know of a resource and specifications to modify my existing distributor for better mileage (I'm getting 14 mpg!) and better throttle response?

An additional point: will I get an improvement in low end throttle response by going to the Euro exhaust? I already have most of the pieces.

I am trying to keep it simple, in terms of alterations. Besides wanting to keep stock appearance and the convenience of the nicely integrated factory package, I also don't want to get too deeply, too fast into this car, which I've only owned for a few months.

 

I'm interested to find out too about the ignition. Yes put the euro exhaust according the Bruce Anderson book when using SC cams euro exhaust allows them to breathe better and improve low rpm running. The best upgrade for exhaust is headers, but if you have the piece and like it stock looking go for the euro. I know that motor meister recurve distributors and 14MPG is pretty good on a 930.