Hi, my 67 has an intermittent start up that I need to fix. The car does start but the starter will kinda slow down right before the car starts. It doesn’t occur if the car is hot or cold and not every time. Do you think it’s the starter, engine timing or something else?

 

Could be the battery is getting weak,could be starter too but first things first.
Have you cleaned your battery terminals and cables lately and made sure they are tight?
Even a non visible film of corrosion can cause this scenario.
Does the car have headers? Often headers will do a number on a starter after a while from heat sink and I see you live in a furnace (lol).