"Why not just add a cheaper aftermarket EI system to my existing distributor housing?"
There are quite a few reasons why it is better to "spend the money now" on an electronic ignition. But most simply, switching out the mechanical ignition points alone does not address common areas of failure on these 40+ year old units, there is always underlying wear, often severe. I have now dismantled hundreds of Roadster distributors for these upgrades, and they are almost all suffering in one or more areas. I personally used an aftermarket system with no known problems. Then I swapped mine out for a new East Coast Roadster Distributor and immediately was impressed by the performance increase. I had gotten used to the reliability and quick starting with EI, but I was quite surprised at the increased low end power and general increase in power on acceleration. When I took my old distributor apart, I found most of the following:
A new distributor might seem like a significant expense on the surface, but, it has been carefully rebuilt with all tolerances measured and set. The mechanical advance is set-up to 7.5 degrees (pre-smog settings), the mechanical advance springs and the weights are matched to the shafts to eliminate play and give a proper advance curve. On SU carb models, a properly functioning vacuum advance is installed. On Solex models we eliminate the vacuum advance and lock the breaker plate. Everything moving gets a quality synthetic hi temperature grease application. All of the electronic ignition components are OEM Nissan specification, the distributor is either clean bare aluminum or painted so it looks as good as it works and only a high quality brass contact distributor cap and rotor is installed - details, details, details. Finally the East Coast Roadster Distributor carries a limited lifetime exchange warranty for all mechanical parts.
We offer top quality custom re-manufactured electronic ignition distributors designed as "drop-in" solutions to easily replace the points and condenser-based original equipment systems delivered with these classic cars. Our bolt in replacement offers increased performance, reliability, drivability and improved gas mileage to make your driving experience as enjoyable as possible!