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distributor

Posted: Sun Dec 03, 2017 7:01 pm
by james butler
ive been wondering
i changed the dizzy in my car a couple of years back with a spare from a dx engine car, mines an ex carbed version.
so what do i time the ignition too?
its currently set at 18 degrees BTDC and runs great but.......
carbed cars are supposed to be 18 degrees BTDC and injection is 6 i think?
so which am i supposed to be using and what determines it? is it a cam thing or something else thats the reason why they are different?

regards

james

Re: distributor

Posted: Sun Dec 03, 2017 7:38 pm
by mark1gls
I’ve never bothered with a timing gun, I advance mine till it “pinks” under load the retard it a little till it stops.
As long as it’s running well and not “pinking” I would not worry about what the book says, you can advance it a little over factory setting to give it a little bit more go.
I guess it might change slightly depending on the quality of the petrol? In my DX golf I use petrol from 97 to 99 RON depending on where I go....

Re: distributor

Posted: Sun Dec 03, 2017 8:06 pm
by james butler
mark1gls wrote:I’ve never bothered with a timing gun, I advance mine till it “pinks” under load the retard it a little till it stops.
thats all well and good and i know it works but why the large gap betwen 18 and 6 degrees?
its not even close, so surely something must be different between the 2 types?

Re: distributor

Posted: Mon Dec 04, 2017 10:58 am
by unknownmale
I know Ex and Dx dizzys have different part numbers but i run dizzy of a DX on my EX engine with no issue. I only run Vpower but not sure what timing it's at as I also do what Mark does above.

If ever I run regular unleaded I have to advance the timing slightly or the car diesels when I shut it off.

I'm not sure about the timing difference, but assume it's because the carbed cars are pulling in the AF mixture at the same time the mixture can be ignited earlier where as the MFI cars inject the fuel closer to ignition?