Davis Unified Ignition question

[pazcarguy]

I am building a 66 289 engine for a Cobra kit car and was wondering if anyone has used one of these. My question is in regards to "fit". I plan on using an Edelbrock RPM airgap manifold and was concerned about getting full advance/retard by turning the distributor to its limits to set the timing. I know this is larger in diameter than a Mallory unit I had before (in a similar 289 but I was using an F4B intake at that time) and with the Mallory, I could not get full movement with a smaller cap. Davis wants a 20% restock fee and I dont want to buy if it wont work. I like this as it is a single wire setup to keep the engine bay clean and they will set advance curve (mechanical) to my vehicle by weight, type trans. cam specs, etc. Anyone using one and pros and cons? Thanks in advance. Brian

 

[D.Hearne]

Buying to keep the engine bay "cleaner" is a poor excuse for ibuying one of these. You have one wire hookup with a points distributor as well. The physical size of the DUI defeats the whoel purpose of trying for a "cleaner" engine bay. Replace the points with a Pertronix or any other electronic module and you have a two wire setup, encase these in wire loom and you're back to a one wire look. I get a kick out of those claiming a one wire deal. What's complicated about one more wire? One to positive, one to negative.

 

[ron67fb]

If you can't get full movement you need to move the distributor shaft a tooth. How much movement do you need and how often? It's not like you're constantly advancing/retarding your timing 20 degrees.