5 replies to this topic

[monster_mini]

Hi,

i'm just trying to find out what the optimum timing(without going on a rolling road and trying different settings) is for the metro electronic dizzy with the module on the side?

The engine is a rebuilt 1275 cc engine (being started for the first time tomorrow),

modified cylinder head (not ott just nicely opened up)

twin 1 1/4" carb's

full minispares 1275 LCB manifold and single box exhaust system(rc40)

thanks

[new_zealand _minis]

try 5 if not then maby 8 , or 12 .. depnds what cam and what compression .. just try them all and go for a drive see whats best

[yellowmonster]

I've got a standard 998 with the same dizzy.
After trying lots of settings I found (and had some feedback with those in the know) that 18-20 degrees BTDC (without the vacuumlead connected, but connected when adjusted) or 28-30 degrees BTDC (if you're not using a vacuumlead at all and block it off) is fine...really.
As mentioned, it depends on cam and compression too, so keep an eye on those plugs and an ear for pinging: telltailes the ignition is too advanced.

Edited by yellowmonster, 07 August 2011 - 10:58 AM.

[monster_mini]

ok thanks

compression ratio is 10 - 1 and the cam is a standard 1275 cam, (not the girly one with the groove inbetween lobe 7 and 8, the proper 1275 one:P)

does that help any more?

[minimender]

I've got a standard 998 with the same dizzy.
After trying lots of settings I found (and had some feedback with those in the know) that 18-20 degrees BTDC (without the vacuumlead connected, but connected when adjusted) or 28-30 degrees BTDC (if you're not using a vacuumlead at all and block it off) is fine...really.
As mentioned, it depends on cam and compression too, so keep an eye on those plugs and an ear for pinging: telltailes the ignition is too advanced.

Are you asking for the maximum advance with the motor revving at 4000rpm or static ign timing?

Maximum advance is trial and error, find out what it likes without pinking under load. Give it (vac pipe off) 30deg and try it. If ok then give it 32 or 33 and see how it goes. Test it on a timer between two points in say third...pas the first point at say 2000rpm and floor it, then see what revs you are doing at the second point.
Then adjust and do it again...if better then give it some more , if worse then back it off a little till it goes best.

Static I would start at 10 degrees, that dizzy will then give you 30 degrees at 4000 rpm

[monster_mini]

ok thanks:)