1980 930 and 1974 911 6 pin CDI box the same

[jimtweet]

I own a 1980 930 and 1974 911 with 3.0 w/ webers.

I just had my 1980 930 Bosch CDI box rebuilt due to a really low whine, also installed new Bosch coil.

I recently purchased a 1974 with 3.0 w. webers. Car runs fine, but when I turn car on I get NO WHINE from CDI box at all.

With my new 930 box it is extremely loud.

I know for a fact both boxes are Bosch 6 pin boxes. I wanted to swap the boxes and see if I hear the whine in the 911 with the 930 box. Are these boxes the same?

Would my 911 CDI box be working if it wasnt whining?

[timmy2]

From the part numbers they are the same.
Maybe each box whines at its own level, like kids...

[jimtweet]

this was all prompted by a jumping tach,...

I replaced voltage regulator and nothing, it only does it at the higher RPMs...

after watching the video a few times on ecudoctors.com this occurred to me

[fintstone]

Of course you realize that the '74 had a 3-pin originally...and the 6-pin was added with the 3.0.

[jimtweet]

Originally Posted by fintstone

Of course you realize that the '74 had a 3-pin originally...and the 6-pin was added with the 3.0.

Yes. I know this is not the box that would have been there for the 2.7