Topic: 66- Intake manifold date code vs block code (6F17)

[jtrue]

Hi I have a 66 GT Fastback. I discovered the other day that it has what looks to be the original engine. The block date code is about a month before the car build date. Over the years someone has installed an aluminum intake. I would like to go back to stock on everything on the car if possible. What is an acceptable date range that I should be looking for on the manifold if my block cast date is June 17, 1966? Thanks for any help.

[J_Speegle]

First welcome to the site - Hope you find your find the information and help here useful in your concours related endeavours

Here are some date spreads for 66 small block production

Hope this helps

Block -------------Intake
5K26                    5K22
5L17                     5K28
6A26                     6A21
6B16                     6C9

[jwc66k]

Hi I have a 66 GT Fastback. I discovered the other day that it has what looks to be the original engine. The block date code is about a month before the car build date. Over the years someone has installed an aluminum intake. I would like to go back to stock on everything on the car if possible. What is an acceptable date range that I should be looking for on the manifold if my block cast date is June 17, 1966? Thanks for any help.

Be careful. There is also an engine assembly date stamped near the distributor. An intake would be date coded prior to the engine assembly date, but would be independent of the engine casting date.
Jim

[jtrue]

Great  information! Thank you, guys.

[Hipo giddyup]

Hi there, I too have a late 66' production Mustang. My engine assembly date looks to be 6G31 and my intake casting is 6G18. Hope this helps.

[jtrue]

Yes, thank you!