BritishV8 Forum

I have read the article on this site about soldering a potentiometer onto the chip inside the tach.

But the inside of my tach does not look like the one in the article.

i believe the article says to solder on posts 4 and 7 (going from memory.)

My question is, which of the posts on the chip are 4 and 7?  How do you count them?

Leon reached out on mgexperience and told me that number one is next to the indentation on top of the chip.

Also, the correction on the pins in the article on this site is incorrect.  It is pins 4 and 7 and not 3 and 8.  Here is Leon's page https://leonsmgb.com/tach-4-cylinder-to-8-cylinder-conversion-or-adjustment/

You can clearly see the indentation on the chip and also his leads on pins 4 and 7.

The confusion with the Figure 1 drawing stems from the capacitor being drawn in the wrong location (pins 3 & 5).  The capacitor actually goes across pins 1 & 7.

http://www.britishv8.org/Articles/MGB-to-V8-Tach-Conversion.htm

https://www.mgexp.com/forum/mg-engine-swaps-forum.40/calibrating-1973-mgb-tachometer.4223333.4223713/page-2#msg-4223713

This is the corrected version.