small block flexplate

[brainsboy]

Whats the deal between the 157 and 164 tooth flexplates which works with what transmissions?

I am having my 351w balanced and I told the machinist I have a C-4 transmission, he said I have to use the 157tooth flexplate the 164 wont work in a C-4. But the C-4 converter I bought has a 11.5" bolt pattern for use with 164tooth flexplates. Something doesnt make sence, anyone know why ford makes two flexplates and which applications are they for? I am thinking the machinist is wrong and the 164tooth flexplates will work in a C-4, but I thought I would ask you guys.

Ben

[TonyMadrid]

I'm not certain why the different sizes of flexplates. I think it may have something to do with some of the earlier small block that had a different bolt pattern for mounting the trans to the block.

I'm running a 351W with a C-4 and I'm using a 164 tooth flex, 28 oz. balance.

BTW, I'm swapping out the C-4 for an AOD and when I removed the C-4 and converter, I noticed that the flex plate is stamped AOD.

I think the 164 tooth is what you need.

Just my opinion, but wait to hear from some of the other gurus in here.

Tony

[Mr.Fixit]

From what I recall, the 164 was used with every ford automatic, except the C-4 years 1968-1976. The C-4 1977+, C-6, and AOD are all supposed to use a 164 tooth.