Voltage drop

[montypsx]

Hi all. how can I check what power my starter is pulling when cranking. If it’s cold I’m not getting 12v to the coil if it’s warm then it starts ok with only a very slight drop to the coil. It seems to only have happened since I’ve done a few mods to the engine e.g 1641 jugs, full flow, 110 cam, twin 34 carbs, ported heads. Any advice would be brill. Thank you

 

[67panel]

The volts will drop to 10 on cold crank giving you a week spark, best thing is to fit a ballasted coil. using a relay fed by the starter crank feed you will get a good voltage at the coil. It will be a 10v coil with the voltage dropped by the ballast , when ballast is bypassed you should still get 10v to the coil. I know easy for me to say (and do) but depends what you are like with leccy stuff.

 

[montypsx]

thanks for the reply, I’m ok with electrics I’ll have a google to see how to do it