reset on cranking -ve coil trigger V3 Ms1

[John_S]

had a search on the forum but couldn't really see anything so here i am asking for advice
the engine is sound (16.0 1/4 mile on carbs plus 1000mile run in )

2110cc aircooled , V3 MS1 (code that it came with) , triggering off coil -ve (with ahem points - cause me electronic ignition fried).

i'm using the relay board and this is grounded straight back to battery (so is the 12v feed).

i've taken X1 (cut jumper to X2 ) to a spare pin and grounded direct to battery,

Shielding the tacho has helped a bit , i'm also going to return the sheild direct to the battery cause i was returning to ground on relay board

the MS unit is fully built with only the mods above

any ideas i'd be gratefull

thanks

John

[jsmcortina]

Have you tried putting a resistor in series with the tach input? Check out the megamanual, there is plenty of discussion about tach signals.

James

[John_S]

the megamanual seams mainly to go about moding the V2.2 board where i have a V3 (all these mods done ?? )

is there some starting values to try (i'll see what i have , maybe i'll find a good old 1k ) is it worth upping the value of c30 dave capacitor ?? )

edit of post .....

thing i got ready to try are
1. resistor inline with tacho (set at 500 ohm , i can go up to 1k)
2. diode so i can clap ringing to ground
3. wiring so i can jump relay board
4. input cap (the dave one) to go higher , this slugs ringing even more

John