Bill Wrote: I am corresponding with an owner Re: spark advance. As we all know, DMC decided to use only one centrifugal counterweight inside its distributors rather than two (Volvo used two on its imports to the exact same North American market). >> Have you ever actually taken a DMC dizzy apart? If you had, you'd know this is plain wrong. They use two bob weights, same as all the others. But they're not identical. To compensate, DMC: - Bumped base ignition time from 10 to 13 degrees BTDC >> WHY would that make ANY difference? It's not a compensation of any sort, it's to run cleaner emissions at idle, which is when they're tested. The rest of the advance curve is designed to start at 13, unlike the other setups designed to start at 10. It generates an advance curve, a graph, a table.... the sort of thing you do graphically in an EFI setup/ - Ran full manifold vacuum rather than ported vacuum to the advance diaphragm >> Have you ever measured the difference? The ported vacuum is just as capable of maxing out the advance diaphragm. Why have the vacuum solenoid? To make SURE there is zero vacuum at idle, nothing more. My question: Why did DMC find it necessary to reinvent the spark advance wheel? >> STOP saying everything was down to DMC will you?!?! I have built a DeLorean engine based on a crate Volvo B28F and they were functionally IDENTICAL. More engineering from Dunmurry that causes me to scratch my head. >> The engine came from RENAULT **drums fingers on the table, gritted teeth** Martin [Non-text portions of this message have been removed] To address comments privately to the moderating team, please address: moderators@xxxxxxxxxxx For more info on the list, tech articles, cars for sale see www.dmcnews.com To search the archives or view files, log in at http://groups.yahoo.com/group/dmcnews Yahoo! Groups Links <*> To visit your group on the web, go to: http://groups.yahoo.com/group/dmcnews/ <*> Your email settings: Individual Email | Traditional <*> To change settings online go to: http://groups.yahoo.com/group/dmcnews/join (Yahoo! ID required) <*> To change settings via email: mailto:dmcnews-digest@xxxxxxxxxxxxxxx mailto:dmcnews-fullfeatured@xxxxxxxxxxxxxxx <*> To unsubscribe from this group, send an email to: dmcnews-unsubscribe@xxxxxxxxxxxxxxx <*> Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/