64 car, 72 engine ;-)
urban. thx for info on 351 (164) alwayts wondered what they were for

if you change the gearbox or belhousing I cannot see a reason to change the tooth count.
As the starter remains the same and should sit in the exact same position as before

 

Be careful on that 320/157, 351w/164 rule. My GT40 has a zero balance 347 (stroked 302) with a 164 tooth flywheel and diaphram clutch.

 

Fake, you taught me my one thing to learn today . I had not idea a short deck small block would run a 164.

 

That's why I like this site, you can cut through all the crap you hear from other people and get to the real answers. I'm glad I didn't buy the 164 tooth the guy was swearing that it was correct for me as he took it off of a '66 with 289. Kinda like the guy that sold me a pedal set from a '66 Mustang coupe, however the frame was completely different from the stock auto one in my car. Fortunately I was able to switch out the pedals and use my original frame.

Thanks guys.