distr dwell, willys jeep

I'm working on the ignition on a 1962 willys, 6cyl and have the distr up on the distr machine.
It has about 25deg of dwell, the book says i need 39deg and i can't figure out how to do it.
It is an old Autolite distributor - anybody mess with these?

 

Decrease the point gap.

 

This might just teach you a little more than you thought you wanted to know about the subject. It was a bit of a refresher course for me!

http://what-when-how.com/automobile/conventional-ignition-systems-automobile/

 

What OJ said. Dwell is a function of point gap. IF you don't have a dwell machine, .016 gap seems to be a good starting point. Remember closer the gap, easier starting, but you lose top end. Wider the gap, harder to start, but will run better at top end. OR so I was told.

 

Between each firing is 60 degrees of distributor rotation.



The larger the gap the less the time points are closed, and vice versa.

 

39 deg dwell seems a tad high...shouldnt it be 36 degrees? Also, remember that the
dwell is distributor degrees. If you are sure you have 25 deg now and cant get it higher by adjusting the points, look at the fiber (or plastic) rub strip that contacts the distributor cam....does it appear to be worn off? How much point gap do you have when the rub strip is on the flat of the distributor cam (not the high spots on the lobes)?

 

.020" point gap gets my Super Hurricane to 39 degrees checked with a dwell meter. The engine starts good.

 

It is indeed .020 Gap, 39 degrees, those engines must have a little faster points open slope than the typical .018 36 GM 6.

 

If you want your head to hurt, think about that engine turning 3000 rpm. The distributor is turning 1/2 speed so it is spinning 1500 rpm. Every 60 seconds, the distributor rotates 1500 times.....so every second, the distributor rotates 1500/60 = 25 times. For a six cylinder, that means there are 6 x 25 firing events = 150 firings. So, the points/coil fire every 1 sec / 150 = 0.0067 seconds. Points ain't closed long, (39 deg/60 deg per cyl) times 0.0067 sec = 0.0043 sec closed. Sound right? Ouch, that hurts.

 

Thanks Mike, this is some good info. The points are aftermarket and i bet the 'rub' part is too narrow. I am looking for some NOS points for the motor, i did find an original NOS vacuum pot and it should be here today - the existing had a vacuum leak.
Thanks for all the responses, oj