electrical and ignition Roundie and square tail distributors

[stricht8]

Do a 73 and a 75 share the same ignition components, ie. points, condenser, cap, rotor?

 

My '73 has what appears to be a later distributor part number so not sure which parts to order!

[Simeon]

Lots of variations in distributors through the years with points in different configuration and different cap arrangements. I would send Blunt your distributor number and get him to identify the correct parts. Even the condenser varies with a square or a round hole through the body. 

[TobyB]

There are 2 styles of cap-  'early' dizzy has a tab that sticks up from 1 of the hold-down clips.

'Late' has a notch cut out of the barrel of the dizzy, and the cap has a tab.  And is a vw part

 

I think they changed in '71,  but don't quote me.

 

Rotors all interchange.  and are vw.

 

Now, the actual dizzy spec varied a lot... 

 

t

['76mintgrün'02]

Rotors all fit, but there are two kinds to choose from.

One has a wider tip, for the added advance associated with vacuum advance distributors, if I understand it correctly.

With rotors there is also a difference in resistance.

Bosch typically marks them with either an R5 or an R1.

 

My extra VW bits come in handy.

 

EDIT-- the R5 rotor is what the manual calls for.  It makes for a longer spark duration than the 1K rotor.

Edited June 4, 2020 by '76mintgrün'02

[TobyB]

Don't forget the rev- limiting rotor, Tom!  Those were NLA back when I started, but seem to have come back from the dead

(maybe Botch found a big warehouse full of 'em they forgot they had?  Sent one to China by accident?)

 

 

There's also the "whups, guess I have an HEI" rotor

 

and the "guess it's time to do the driver's side mount" rotor...

 

 

 

I'm sure I'm missing a few...

 

hee

 

t

 

[Maximillian]

Great info presented. I would start with WHICH motor do you have in the car as a base point and then decide which path to pursue (updated electronic ignition or old school). So many times I go to a car show and see a non-original motor but somehow it is believed to be original. But thats OK & thats part of the fun of owning a 40yr + old car. Personally I went with updated via Crane ignition and have had zero problems. Call me if you get stuck.

 

Thanks,

Max