Packard Forum Index » Pre-War (1899-1942)

Has any one ever changed from a 6 volt battery to a 8 volt battery on these pre-war cars. Did it improve the headlights being brighter and help turn the motor over better. Does a person have to adjust the voltage reg or make any other changes.for it too work, looking for the pros and cons of it. thanks

Almost universally thought to be a bad idea, one that folks did that were too lazy or not competent to insure good clean connections and grounds. If doing that still doesn't give you enough brightness, clean or replate your reflectors if so used, and/or try halogen bulbs. Running your headlights thru a relay may also help overcome old tired wiring. But please, stay away from 8-volt batteries.

Yes, you had to make compensating adjustments to the charging system.

You do have to change the regulator and make sure the bulbs are rated 6-8v not just 6 and they can still have a shorter life. Some generators don't particularly like to run that high resulting in some stress so something to think about. A few of the accessories (radio being one) don't particularly like the increased voltage either. There is at least one and maybe two of the radio repair places that will not honor warranties if run on 8v. Those are come of the cons.

Pros are it does give a bit more of a cushion to any voltage drop caused by poor connections and the starter does turn a bit faster. Whether it is worth the expense or trouble of changing things and possibly shorter life or even damaged components vs just keeping a well charged battery and clean connections is debatable. It was a common change for poorly maintained cars in the early 50s -- mostly for better winter starting -- where I grew up.

Thanks for your comments and they all make sense to stay with 6 volt like it was spose to be.

Back in the '60s, I tried an 8 volt battery in my 1940 110 and had no particular issues with it (it still had all of its original Mazda bulbs) and then later I used one of the dual batteries that provided 12v to the starter but everything else got 6v and it charged conventionally. Ultimately I converted to 12v but looking back, none of those were really valid fixes in trying to solve the slow cranking and hard starting that it sometimes had when hot. The starter and generator and most everything else had been rebuilt but now I wonder if it was just a simple matter of too small battery cable! A good 6v system should do the job.

The majority of the time with problems like yours the solution is most always a poor ground connection. Starting with where the bulb contact with the socket to where the ground is made to the frame. Also, make sure that you ensure that the ground conntection from the battery to the frame is good.